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multiple stream tube</title> <meta name="description" content="Search results for: double multiple stream tube"> <meta name="keywords" content="double multiple stream tube"> <meta name="viewport" content="width=device-width, initial-scale=1, minimum-scale=1, maximum-scale=1, user-scalable=no"> <meta charset="utf-8"> <link href="https://cdn.waset.org/favicon.ico" type="image/x-icon" rel="shortcut icon"> <link href="https://cdn.waset.org/static/plugins/bootstrap-4.2.1/css/bootstrap.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/plugins/fontawesome/css/all.min.css" rel="stylesheet"> <link href="https://cdn.waset.org/static/css/site.css?v=150220211555" rel="stylesheet"> </head> <body> <header> <div class="container"> <nav class="navbar navbar-expand-lg navbar-light"> <a class="navbar-brand" href="https://waset.org"> <img src="https://cdn.waset.org/static/images/wasetc.png" alt="Open Science Research Excellence" title="Open Science Research Excellence" /> </a> <button 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action="https://publications.waset.org/abstracts/search"> <div id="custom-search-input"> <div class="input-group"> <i class="fas fa-search"></i> <input type="text" class="search-query" name="q" placeholder="Author, Title, Abstract, Keywords" value="double multiple stream tube"> <input type="submit" class="btn_search" value="Search"> </div> </div> </form> </div> </div> <div class="row mt-3"> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Commenced</strong> in January 2007</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Frequency:</strong> Monthly</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Edition:</strong> International</div> </div> </div> <div class="col-sm-3"> <div class="card"> <div class="card-body"><strong>Paper Count:</strong> 7095</div> </div> </div> </div> <h1 class="mt-3 mb-3 text-center" style="font-size:1.6rem;">Search results for: double multiple stream tube</h1> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7095</span> Structural Behaviour of Concrete Energy Piles in Thermal Loadings</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=E.%20H.%20N.%20Gashti">E. H. N. Gashti</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20Malaska"> M. Malaska</a>, <a href="https://publications.waset.org/abstracts/search?q=K.%20Kujala"> K. Kujala</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The thermo-mechanical behaviour of concrete energy pile foundations with different single and double U-tube shapes incorporated was analysed using the Comsol Multi-physics package. For the analysis, a 3D numerical model in real scale of the concrete pile and surrounding soil was simulated regarding actual operation of ground heat exchangers (GHE) and the surrounding ambient temperature. Based on initial ground temperature profile measured in situ, tube inlet temperature was considered to range from 6掳C to 0掳C (during the contraction process) over a 30-day period. Extra thermal stresses and deformations were calculated during the simulations and differences arising from the use of two different systems (single-tube and double-tube) were analysed. The results revealed no significant difference for extra thermal stresses at the centre of the pile in either system. However, displacements over the pile length were found to be up to 1.5-fold higher in the double-tube system than the single-tube system. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=concrete%20energy%20piles" title="concrete energy piles">concrete energy piles</a>, <a href="https://publications.waset.org/abstracts/search?q=stresses" title=" stresses"> stresses</a>, <a href="https://publications.waset.org/abstracts/search?q=displacements" title=" displacements"> displacements</a>, <a href="https://publications.waset.org/abstracts/search?q=thermo-mechanical%20behaviour" title=" thermo-mechanical behaviour"> thermo-mechanical behaviour</a>, <a href="https://publications.waset.org/abstracts/search?q=soil-structure%20interactions" title=" soil-structure interactions"> soil-structure interactions</a> </p> <a href="https://publications.waset.org/abstracts/10541/structural-behaviour-of-concrete-energy-piles-in-thermal-loadings" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/10541.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">214</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7094</span> Determination of Flow Arrangement for Optimum Performance in Heat Exchangers</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ahmed%20Salisu%20Atiku">Ahmed Salisu Atiku</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This task involves the determination of the flow arrangement for optimum performance and the calculation of total heat transfer of two identical double pipe heat exchangers in series. The inner pipe contains the cold water stream at 27掳C, whilst the outer pipe contains the two hot stream of water at 50掳C and 90 掳C which can be mixed in any way desired. The analysis was carried out using counter flow arrangement due to its good heat transfer ability. The best way of heating this cold stream was found out to be passing the 90掳C hot stream through the two heat exchangers. The outlet temperature of the cold stream was found to be 39.6掳C and overall heat transfer of 131.3 kW. Though starting with 50掳C hot stream in the first heat exchanger followed by 90掳C hot stream in the second heat exchanger gives an outlet temperature almost the same as 90掳C hot stream alone, but the heat transfer is low. The reason for the low heat transfer was that only the heat transfer in the second heat exchanger is considered. Whilst the reason behind high outlet temperature was that the cold stream was already preheated by the first stream. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=cold%20stream" title="cold stream">cold stream</a>, <a href="https://publications.waset.org/abstracts/search?q=flow%20arrangement" title=" flow arrangement"> flow arrangement</a>, <a href="https://publications.waset.org/abstracts/search?q=heat%20exchanger" title=" heat exchanger"> heat exchanger</a>, <a href="https://publications.waset.org/abstracts/search?q=hot%20stream" title=" hot stream"> hot stream</a> </p> <a href="https://publications.waset.org/abstracts/51973/determination-of-flow-arrangement-for-optimum-performance-in-heat-exchangers" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/51973.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">323</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7093</span> CFD Study for Normal and Rifled Tube with a Convergence Check</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Sharfi%20Dirar">Sharfi Dirar</a>, <a href="https://publications.waset.org/abstracts/search?q=Shihab%20Elhaj"> Shihab Elhaj</a>, <a href="https://publications.waset.org/abstracts/search?q=Ahmed%20El%20Fatih"> Ahmed El Fatih</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Computational fluid dynamics were used to simulate and study the heated water boiler tube for both normal and rifled tube with a refinement of the mesh to check the convergence. The operation condition was taken from GARRI power station and used in a boundary condition accordingly. The result indicates the rifled tube has higher heat transfer efficiency than the normal tube. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=boiler%20tube" title="boiler tube">boiler tube</a>, <a href="https://publications.waset.org/abstracts/search?q=convergence%20check" title=" convergence check"> convergence check</a>, <a href="https://publications.waset.org/abstracts/search?q=normal%20tube" title=" normal tube"> normal tube</a>, <a href="https://publications.waset.org/abstracts/search?q=rifled%20tube" title=" rifled tube"> rifled tube</a> </p> <a href="https://publications.waset.org/abstracts/37253/cfd-study-for-normal-and-rifled-tube-with-a-convergence-check" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/37253.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">334</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7092</span> Design of Tube Expanders with Groove Shapes to Reduce Deformation of Tube Inner Grooves in Copper Tube Expansion</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=I.%20Sin">I. Sin</a>, <a href="https://publications.waset.org/abstracts/search?q=H.%20Kim"> H. Kim</a>, <a href="https://publications.waset.org/abstracts/search?q=S.%20Park"> S. Park</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Fin-tube heat exchangers have grooves inside tubes to improve heat exchange performance. However, during the tube expansion process, heat exchange efficiency is decreased due to large deformation of tube inner grooves. Therefore, the objective of this study is to design a tube expander with groove shapes on its outer surface to minimize deformation of the inner grooves in copper tube expansion for fin-tube heat exchangers. In order to achieve this goal, first, we have tried to calculate tube inner groove deformation by the currently used tube expander without groove shapes on its surface. The tube inner groove deformation was acquired by elastoplastic finite element analysis from the boundary conditions with one tube end fixed and friction between the tube and tube expander (friction coefficient: 0.15). The tube expansion process was simulated by inserting the tube expander into the tube with a speed of 90 mm/s. The analysis results showed that tube inner groove heights were decreased by approximately 8 % from 0.15 mm to 0.138 mm with stress concentrations observed at the groove end, consistent with experimental results. Based on the current results, we are trying to design a novel shape of the tube expander with grooves to further reduce deformation tube inner grooves in copper tube expansion. For this, we will select major design variables of tube expander groove shapes by conducting sensitivity analysis and then optimize the design variables using the Taguchi method. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=tube%20expansion" title="tube expansion">tube expansion</a>, <a href="https://publications.waset.org/abstracts/search?q=tube%20expander" title=" tube expander"> tube expander</a>, <a href="https://publications.waset.org/abstracts/search?q=heat%20exchanger" title=" heat exchanger"> heat exchanger</a>, <a href="https://publications.waset.org/abstracts/search?q=finite%20element" title=" finite element"> finite element</a> </p> <a href="https://publications.waset.org/abstracts/60394/design-of-tube-expanders-with-groove-shapes-to-reduce-deformation-of-tube-inner-grooves-in-copper-tube-expansion" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/60394.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">326</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7091</span> A More Powerful Test Procedure for Multiple Hypothesis Testing</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shunpu%20Zhang">Shunpu Zhang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> We propose a new multiple test called the minPOP test for testing multiple hypotheses simultaneously. Under the assumption that the test statistics are independent, we show that the minPOP test has higher global power than the existing multiple testing methods. We further propose a stepwise multiple-testing procedure based on the minPOP test and two of its modified versions (the Double Truncated and Left Truncated minPOP tests). We show that these multiple tests have strong control of the family-wise error rate (FWER). A method for finding the p-values of the proposed tests after adjusting for multiplicity is also developed. Simulation results show that the Double Truncated and Left Truncated minPOP tests, in general, have a higher number of rejections than the existing multiple testing procedures. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=multiple%20test" title="multiple test">multiple test</a>, <a href="https://publications.waset.org/abstracts/search?q=single-step%20procedure" title=" single-step procedure"> single-step procedure</a>, <a href="https://publications.waset.org/abstracts/search?q=stepwise%20procedure" title=" stepwise procedure"> stepwise procedure</a>, <a href="https://publications.waset.org/abstracts/search?q=p-value%20for%20multiple%20testing" title=" p-value for multiple testing"> p-value for multiple testing</a> </p> <a href="https://publications.waset.org/abstracts/183745/a-more-powerful-test-procedure-for-multiple-hypothesis-testing" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/183745.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">83</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7090</span> Condensation Heat Transfer and Pressure Drop of R-134a Flowing inside Dimpled Tubes</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Kanit%20Aroonrat">Kanit Aroonrat</a>, <a href="https://publications.waset.org/abstracts/search?q=Somchai%20Wongwises"> Somchai Wongwises</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A heat exchanger is one of the vital parts in a wide variety of applications. The tube with surface modification is generally referred to as an enhanced tube. With this, the thermal performance of the heat exchanger is improved. A dimpled tube is one of many kinds of enhanced tube. The heat transfer and pressure drop of two-phase flow inside dimpled tubes have received little attention in the literature, despite of having an important role in the development of refrigeration and air conditioning systems. As a result, the main aim of this study is to investigate the condensation heat transfer and pressure drop of refrigerant-134a flowing inside dimpled tubes. The test section is a counter-flow double-tube heat exchanger, which the refrigerant flows in the inner tube and water flows in the annulus. The inner tubes are one smooth tube and three dimpled tubes with different helical pitches. All test tubes are made from copper with an inside diameter of 8.1 mm and length of 1500 mm. The experiments are conducted over mass fluxes ranging from 300 to 500 kg/m虏s, heat flux ranging from 10 to 20 kW/m虏, and condensing temperature ranging from 40 to 50 藲C. The results show that all dimpled tubes provide higher heat transfer coefficient and frictional pressure drop compared to the smooth tube. In addition, the heat transfer coefficient and frictional pressure drop increase with decreasing of helical pitch. It can be observed that the dimpled tube with lowest helical pitch yields the heat transfer enhancement in the range of 60-89% with the frictional pressure drop increase of 289-674% in comparison to the smooth tube. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=condensation" title="condensation">condensation</a>, <a href="https://publications.waset.org/abstracts/search?q=dimpled%20tube" title=" dimpled tube"> dimpled tube</a>, <a href="https://publications.waset.org/abstracts/search?q=heat%20transfer" title=" heat transfer"> heat transfer</a>, <a href="https://publications.waset.org/abstracts/search?q=pressure%20drop" title=" pressure drop"> pressure drop</a> </p> <a href="https://publications.waset.org/abstracts/105152/condensation-heat-transfer-and-pressure-drop-of-r-134a-flowing-inside-dimpled-tubes" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/105152.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">215</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7089</span> Numerical Study of Flow around Flat Tube between Parallel Walls</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hamidreza%20Bayat">Hamidreza Bayat</a>, <a href="https://publications.waset.org/abstracts/search?q=Arash%20Mirabdolah%20Lavasani"> Arash Mirabdolah Lavasani</a>, <a href="https://publications.waset.org/abstracts/search?q=Meysam%20Bolhasani"> Meysam Bolhasani</a>, <a href="https://publications.waset.org/abstracts/search?q=Sajad%20Moosavi"> Sajad Moosavi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Flow around a flat tube is studied numerically. Reynolds number is defined base on equivalent circular tube and it is varied in range of 100 to 300. Equations are solved by using finite volume method and results are presented in form of drag and lift coefficient. Results show that drag coefficient of flat tube is up to 66% lower than circular tube with equivalent diameter. In addition, by increasing l/D from 1 to 2, the drag coefficient of flat tube is decreased about 14-27%. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laminar%20flow" title="laminar flow">laminar flow</a>, <a href="https://publications.waset.org/abstracts/search?q=flat-tube" title=" flat-tube"> flat-tube</a>, <a href="https://publications.waset.org/abstracts/search?q=drag%20coefficient" title=" drag coefficient"> drag coefficient</a>, <a href="https://publications.waset.org/abstracts/search?q=cross-flow" title=" cross-flow"> cross-flow</a>, <a href="https://publications.waset.org/abstracts/search?q=heat%20exchanger" title=" heat exchanger"> heat exchanger</a> </p> <a href="https://publications.waset.org/abstracts/14593/numerical-study-of-flow-around-flat-tube-between-parallel-walls" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/14593.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">503</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7088</span> The Design of Acoustic Horns for Ultrasonic Aided Tube Double Side Flange Making</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Kuen-Ming%20Shu">Kuen-Ming Shu</a>, <a href="https://publications.waset.org/abstracts/search?q=Jyun-Wei%20Chen"> Jyun-Wei Chen</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Encapsulated O-rings are specifically designed to address the problem of sealing the most hostile chemicals and extreme temperature applications. Ultrasonic vibration hot embossing and ultrasonic welding techniques provide a fast and reliable method to fabricate encapsulated O-ring. This paper performs the design and analysis method of the acoustic horns with double extrusion to process tube double side flange simultaneously. The paper deals with study through Finite Element Method (FEM) of ultrasonic stepped horn used to process a capsulated O-ring, the theoretical dimensions of horns, and their natural frequencies and amplitudes are obtained through the simulations of COMOSOL software. Furthermore, real horns were fabricated, tested and verified to proof the practical utility of these horns. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=encapsulated%20O-rings" title="encapsulated O-rings">encapsulated O-rings</a>, <a href="https://publications.waset.org/abstracts/search?q=ultrasonic%20vibration%20hot%20embossing" title=" ultrasonic vibration hot embossing"> ultrasonic vibration hot embossing</a>, <a href="https://publications.waset.org/abstracts/search?q=flange%20making" title=" flange making"> flange making</a>, <a href="https://publications.waset.org/abstracts/search?q=acoustic%20horn" title=" acoustic horn"> acoustic horn</a>, <a href="https://publications.waset.org/abstracts/search?q=finite%20element%20analysis" title=" finite element analysis"> finite element analysis</a> </p> <a href="https://publications.waset.org/abstracts/31506/the-design-of-acoustic-horns-for-ultrasonic-aided-tube-double-side-flange-making" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/31506.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">317</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7087</span> Numerical Investigation of Thermal-Hydraulic Performance of a Flat Tube in Cross-Flow of Air</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hamidreza%20Bayat">Hamidreza Bayat</a>, <a href="https://publications.waset.org/abstracts/search?q=Arash%20Mirabdolah%20Lavasani"> Arash Mirabdolah Lavasani</a>, <a href="https://publications.waset.org/abstracts/search?q=Meysam%20Bolhasani"> Meysam Bolhasani</a>, <a href="https://publications.waset.org/abstracts/search?q=Sajad%20Moosavi"> Sajad Moosavi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Heat transfer from flat tube is studied numerically. Reynolds number is defined base on equivalent circular tube which is varied in range of 100 to 300. In these range of Reynolds number flow is considered to be laminar, unsteady, and incompressible. Equations are solved by using finite volume method. Results show that increasing l/D from 1 to 2 has insignificant effect on heat transfer and Nusselt number of flat tube is slightly lower than circular tube. However, thermal-hydraulic performance of flat tube is up to 2.7 times greater than circular tube. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=laminar%20flow" title="laminar flow">laminar flow</a>, <a href="https://publications.waset.org/abstracts/search?q=flat%20tube" title=" flat tube"> flat tube</a>, <a href="https://publications.waset.org/abstracts/search?q=convective%20heat%20transfer" title=" convective heat transfer"> convective heat transfer</a>, <a href="https://publications.waset.org/abstracts/search?q=heat%20exchanger" title=" heat exchanger"> heat exchanger</a> </p> <a href="https://publications.waset.org/abstracts/14592/numerical-investigation-of-thermal-hydraulic-performance-of-a-flat-tube-in-cross-flow-of-air" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/14592.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">440</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7086</span> Ultimate Stress of the Steel Tube in Circular Concrete-Filled Steel Tube Stub Columns Subjected to Axial Compression</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Siqi%20Lin">Siqi Lin</a>, <a href="https://publications.waset.org/abstracts/search?q=Yangang%20Zhao"> Yangang Zhao</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Concrete-filled steel tube column achieves the excellent performance of high strength, stiffness, and ductility due to the confinement from the steel tube. Well understanding the stress of the steel tube is important to make clear the confinement effect. In this paper, the ultimate stress of the steel tube in circular concrete-filled steel tube columns subjected to axial compression was studied. Experimental tests were conducted to investigate the effects of the parameters, including concrete strength, steel strength, and D/t ratio, on the ultimate stress of the steel tube. The stress of the steel tube was determined by employing the Prandtl-Reuss flow rule associated with isotropic strain hardening. Results indicate that the stress of steel tube was influenced by the parameters. Specimen with higher strength ratio fy/fc and smaller D/t ratio generally leads to a higher utilization efficiency of the steel tube. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=concrete-filled%20steel%20tube" title="concrete-filled steel tube">concrete-filled steel tube</a>, <a href="https://publications.waset.org/abstracts/search?q=axial%20compression" title=" axial compression"> axial compression</a>, <a href="https://publications.waset.org/abstracts/search?q=ultimate%20stress" title=" ultimate stress"> ultimate stress</a>, <a href="https://publications.waset.org/abstracts/search?q=utilization%20efficiency" title=" utilization efficiency"> utilization efficiency</a> </p> <a href="https://publications.waset.org/abstracts/71468/ultimate-stress-of-the-steel-tube-in-circular-concrete-filled-steel-tube-stub-columns-subjected-to-axial-compression" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/71468.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">425</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7085</span> An Investigation on Designing and Enhancing the Performance of H-Darrieus Wind Turbine of 10KW at the Medium Range of Wind Speed in Vietnam</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Ich%20Long%20Ngo">Ich Long Ngo</a>, <a href="https://publications.waset.org/abstracts/search?q=Dinh%20Tai%20Dang"> Dinh Tai Dang</a>, <a href="https://publications.waset.org/abstracts/search?q=Ngoc%20Tu%20Nguyen"> Ngoc Tu Nguyen</a>, <a href="https://publications.waset.org/abstracts/search?q=Minh%20Duc%20Nguyen"> Minh Duc Nguyen</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper describes an investigation on designing and enhancing the performance of H-Darrieus wind turbine (HDWT) of 10kW at the medium wind speed. The aerodynamic characteristics of this turbine were investigated by both theoretical and numerical approaches. The optimal design procedure was first proposed to enhance the power coefficient under various effects, such as airfoil type, number of blades, solidity, aspect ratio, and tip speed ratio. As a result, the overall design of the 10kW HDWT was well achieved, and the power characteristic of this turbine was found by numerical approach. Additionally, the maximum power coefficient predicted is up to 0.41 at the tip speed ratio of 3.7 and wind speed of 8 m/s. Particularly, a generalized correlation of power coefficient with tip speed ratio and wind speed is first proposed. These results obtained are very useful for enhancing the performance of the HDWTs placed in a country with high wind power potential like Vietnam. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=computational%20fluid%20dynamics" title="computational fluid dynamics">computational fluid dynamics</a>, <a href="https://publications.waset.org/abstracts/search?q=double%20multiple%20stream%20tube" title=" double multiple stream tube"> double multiple stream tube</a>, <a href="https://publications.waset.org/abstracts/search?q=h-darrieus%20wind%20turbine" title=" h-darrieus wind turbine"> h-darrieus wind turbine</a>, <a href="https://publications.waset.org/abstracts/search?q=renewable%20energy" title=" renewable energy"> renewable energy</a> </p> <a href="https://publications.waset.org/abstracts/163982/an-investigation-on-designing-and-enhancing-the-performance-of-h-darrieus-wind-turbine-of-10kw-at-the-medium-range-of-wind-speed-in-vietnam" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/163982.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">118</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7084</span> Study on Bending Characteristics of Square Tube Using Energy Absorption Part</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shigeyuki%20Haruyama">Shigeyuki Haruyama</a>, <a href="https://publications.waset.org/abstracts/search?q=Zefry%20Darmawan"> Zefry Darmawan</a>, <a href="https://publications.waset.org/abstracts/search?q=Ken%20Kaminishi"> Ken Kaminishi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In the square tube subjected to the bending load, the rigidity of the entire square tube is reduced when a collapse occurs due to local stress concentration. Therefore, in this research, the influence of bending load on the square tube with attached energy absorbing part was examined and reported. The analysis was conducted by using Finite Element Method (FEM) to produced bending deflection and buckling points. Energy absorption was compared from rigidity of attached part and square tube body. Buckling point was influenced by the rigidity of attached part and the thickness rate of square tube. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=energy%20absorber" title="energy absorber">energy absorber</a>, <a href="https://publications.waset.org/abstracts/search?q=square%20tube" title=" square tube"> square tube</a>, <a href="https://publications.waset.org/abstracts/search?q=bending" title=" bending"> bending</a>, <a href="https://publications.waset.org/abstracts/search?q=rigidity" title=" rigidity"> rigidity</a> </p> <a href="https://publications.waset.org/abstracts/64216/study-on-bending-characteristics-of-square-tube-using-energy-absorption-part" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/64216.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">244</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7083</span> Comparative Evaluation of Vanishing Interfacial Tension Approach for Minimum Miscibility Pressure Determination</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Waqar%20Ahmad%20Butt">Waqar Ahmad Butt</a>, <a href="https://publications.waset.org/abstracts/search?q=Gholamreza%20Vakili%20Nezhaad"> Gholamreza Vakili Nezhaad</a>, <a href="https://publications.waset.org/abstracts/search?q=Ali%20Soud%20Al%20Bemani"> Ali Soud Al Bemani</a>, <a href="https://publications.waset.org/abstracts/search?q=Yahya%20Al%20Wahaibi"> Yahya Al Wahaibi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Minimum miscibility pressure (MMP) plays a great role in determining the displacement efficiency of different gas injection processes. Experimental techniques for MMP determination include industrially recommended slim tube, vanishing interfacial tension (VIT) and rising bubble apparatus (RBA). In this paper, MMP measurement study using slim tube and VIT experimental techniques for two different crude oil samples (M and N) both in live and stock tank oil forms is being presented. VIT measured MMP values for both 'M' and 'N' live crude oils were close to slim tube determined MMP values with 6.4 and 5 % deviation respectively. Whereas for both oil samples in stock tank oil form, VIT measured MMP showed a higher unacceptable deviation from slim tube determined MMP. This higher difference appears to be related to high stabilized crude oil heavier fraction and lack of multiple contacts miscibility. None of the different nine deployed crude oil and CO2 MMP computing correlations could result in reliable MMP, close to slim tube determined MMP. Since VIT determined MMP values for both considered live crude oils are in close match with slim tube determined MMP values, it confirms reliable, reproducible, rapid and cheap alternative for live crude oil MMP determination. Whereas VIT MMP determination for stock tank oil case needed further investigation about stabilization / destabilization mechanism of oil heavier ends and multiple contacts miscibility development issues. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=minimum%20miscibility%20pressure" title="minimum miscibility pressure">minimum miscibility pressure</a>, <a href="https://publications.waset.org/abstracts/search?q=interfacial%20tension" title=" interfacial tension"> interfacial tension</a>, <a href="https://publications.waset.org/abstracts/search?q=multiple%20contacts%20miscibility" title=" multiple contacts miscibility"> multiple contacts miscibility</a>, <a href="https://publications.waset.org/abstracts/search?q=heavier%20ends" title=" heavier ends"> heavier ends</a> </p> <a href="https://publications.waset.org/abstracts/50439/comparative-evaluation-of-vanishing-interfacial-tension-approach-for-minimum-miscibility-pressure-determination" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/50439.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">268</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7082</span> Study on Multi-Point Stretch Forming Process for Double Curved Surface</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Jiwoo%20Park">Jiwoo Park</a>, <a href="https://publications.waset.org/abstracts/search?q=Junseok%20Yoon"> Junseok Yoon</a>, <a href="https://publications.waset.org/abstracts/search?q=Jeong%20Kim"> Jeong Kim</a>, <a href="https://publications.waset.org/abstracts/search?q=Beomsoo%20Kang"> Beomsoo Kang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Multi-Point Stretch Forming (MPSF) process is suitable for flexible manufacturing, and it has several advantages including that it could be applied to various forming such as sheet metal forming, single curved surface forming and double curved one. In this study, a systematic numerical simulation was carried out for atypical double curved surface forming using the multiple die stretch forming process. In this simulation, urethane pads were defined based on hyper-elastic material model as a cushion for the smooth forming surface. The deformation behaviour on elastic recovery was also investigated to consider the exact result after the last forming process, and then the experiment was also carried out to confirm the formability of this forming process. By comparing the simulation and experiment results, the suitability of the multiple die stretch forming process for the atypical double curved surface was verified. Consequently, it is confirmed that the multi-point stretch forming process has the capability and feasibility of being used to manufacture the double curved surfaces of sheet metal. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=multi-point%20stretch%20forming" title="multi-point stretch forming">multi-point stretch forming</a>, <a href="https://publications.waset.org/abstracts/search?q=double%20curved%20surface" title=" double curved surface"> double curved surface</a>, <a href="https://publications.waset.org/abstracts/search?q=numerical%20simulation" title=" numerical simulation"> numerical simulation</a>, <a href="https://publications.waset.org/abstracts/search?q=manufacturing" title=" manufacturing"> manufacturing</a> </p> <a href="https://publications.waset.org/abstracts/7221/study-on-multi-point-stretch-forming-process-for-double-curved-surface" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/7221.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">480</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7081</span> Numerical Investigation of Two Turbulence Models for Predicting the Temperature Separation in Conical Vortex Tube</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20Guen">M. Guen</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A three-dimensional numerical study is used to analyze the behavior of the flow inside a vortex tube. The vortex tube or Ranque-Hilsch vortex tube is a simple device which is capable of dividing compressed air from the inlet nozzle tangentially into two flow with different temperatures warm and cold. This phenomenon is known from literature by temperature separation. The K 蠅-SST and K-蔚 turbulence models are used to predict the turbulent flow behaviour inside the tube. The vortex tube is an Exair 708 slpm (25 scfm) commercial tube. The cold and hot exits areas are 30.2 and 95 mm2 respectively. The vortex nozzle consists of 6 straight slots; the height and the width of each slot are 0.97 mm and 1.41 mm. The total area normal to the flow associated with six nozzles is therefore 8.15 mm 2. The present study focuses on a comparison between two turbulence models K 蠅-SST, K-蔚 by using a new configuration of vortex tube (Conical Vortex Tube). The performance curves of the temperature separation versus cold outlet mass fraction were calculated and compared with experimental and numerical study of other researchers. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=conical%20vortex%20tube" title="conical vortex tube">conical vortex tube</a>, <a href="https://publications.waset.org/abstracts/search?q=temperature%20separation" title=" temperature separation"> temperature separation</a>, <a href="https://publications.waset.org/abstracts/search?q=cold%20mass%20fraction" title=" cold mass fraction"> cold mass fraction</a>, <a href="https://publications.waset.org/abstracts/search?q=turbulence" title=" turbulence"> turbulence</a> </p> <a href="https://publications.waset.org/abstracts/42531/numerical-investigation-of-two-turbulence-models-for-predicting-the-temperature-separation-in-conical-vortex-tube" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/42531.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">249</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7080</span> Failure Analysis of Fuel Pressure Supply from an Aircraft Engine</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20Pilar%20Valles-gonzalez">M. Pilar Valles-gonzalez</a>, <a href="https://publications.waset.org/abstracts/search?q=Alejandro%20Gonzalez%20Meije"> Alejandro Gonzalez Meije</a>, <a href="https://publications.waset.org/abstracts/search?q=Ana%20Pastor%20Muro"> Ana Pastor Muro</a>, <a href="https://publications.waset.org/abstracts/search?q=Maria%20Garcia-Martinez"> Maria Garcia-Martinez</a>, <a href="https://publications.waset.org/abstracts/search?q=Beatriz%20Gonzalez%20Caballero"> Beatriz Gonzalez Caballero</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper studies a failure case of a fuel pressure supply tube from an aircraft engine. Multiple fracture cases of the fuel pressure control tube from aircraft engines have been reported. The studied set was composed of the mentioned tube, a welded connecting pipe, where the fracture has been produced, and a union nut. The fracture has been produced in one most critical zones of the tube, in a region next to the supporting body of the union nut to the connector. The tube material was X6CrNiTi18-10, an austenitic stainless steel. Chemical composition was determined using an X-Ray fluorescence spectrometer (XRF) and combustion equipment. Furthermore, the material has been mechanical, by hardness test, and microstructural characterized using a stereomicroscope and an optical microscope. The results confirmed that it is within specifications. To determine the macrofractographic features, a visual examination and a stereo microscope of the tube fracture surface have been carried out. The results revealed a tube plastic macrodeformation, surface damaged, and signs of a possible corrosion process. Fracture surface was also inspected by scanning electron microscopy (FE-SEM), equipped with a microanalysis system by X-ray dispersive energy (EDX), to determine the microfractographic features in order to find out the failure mechanism involved in the fracture. Fatigue striations, which are typical from a progressive fracture by a fatigue mechanism, have been observed. The origin of the fracture has been placed in defects located on the outer wall of the tube, leading to a final overload fracture. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=aircraft%20engine" title="aircraft engine">aircraft engine</a>, <a href="https://publications.waset.org/abstracts/search?q=fatigue" title=" fatigue"> fatigue</a>, <a href="https://publications.waset.org/abstracts/search?q=FE-SEM" title=" FE-SEM"> FE-SEM</a>, <a href="https://publications.waset.org/abstracts/search?q=fractography" title=" fractography"> fractography</a>, <a href="https://publications.waset.org/abstracts/search?q=fracture" title=" fracture"> fracture</a>, <a href="https://publications.waset.org/abstracts/search?q=fuel%20tube" title=" fuel tube"> fuel tube</a>, <a href="https://publications.waset.org/abstracts/search?q=microstructure" title=" microstructure"> microstructure</a>, <a href="https://publications.waset.org/abstracts/search?q=stainless%20steel" title=" stainless steel"> stainless steel</a> </p> <a href="https://publications.waset.org/abstracts/133219/failure-analysis-of-fuel-pressure-supply-from-an-aircraft-engine" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/133219.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">153</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7079</span> Peristaltic Transport of a Jeffrey Fluid with Double-Diffusive Convection in Nanofluids in the Presence of Inclined Magnetic Field</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Safia%20Akram">Safia Akram</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this article, the effects of peristaltic transport with double-diffusive convection in nanofluids through an asymmetric channel with different waveforms is presented. Mathematical modelling for two-dimensional and two directional flows of a Jeffrey fluid model along with double-diffusive convection in nanofluids are given. Exact solutions are obtained for nanoparticle fraction field, concentration field, temperature field, stream functions, pressure gradient and pressure rise in terms of axial and transverse coordinates under the restrictions of long wavelength and low Reynolds number. With the help of computational and graphical results the effects of Brownian motion, thermophoresis, Dufour, Soret, and Grashof numbers (thermal, concentration, nanoparticles) on peristaltic flow patterns with double-diffusive convection are discussed. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=nanofluid%20particles" title="nanofluid particles">nanofluid particles</a>, <a href="https://publications.waset.org/abstracts/search?q=peristaltic%20flow" title=" peristaltic flow"> peristaltic flow</a>, <a href="https://publications.waset.org/abstracts/search?q=Jeffrey%20fluid" title=" Jeffrey fluid"> Jeffrey fluid</a>, <a href="https://publications.waset.org/abstracts/search?q=magnetic%20field" title=" magnetic field"> magnetic field</a>, <a href="https://publications.waset.org/abstracts/search?q=asymmetric%20channel" title=" asymmetric channel"> asymmetric channel</a>, <a href="https://publications.waset.org/abstracts/search?q=different%20waveforms" title=" different waveforms"> different waveforms</a> </p> <a href="https://publications.waset.org/abstracts/71169/peristaltic-transport-of-a-jeffrey-fluid-with-double-diffusive-convection-in-nanofluids-in-the-presence-of-inclined-magnetic-field" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/71169.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">381</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7078</span> Numerical Study of an Impinging Jet in a Coflow Stream</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Rim%20Ben%20Kalifa">Rim Ben Kalifa</a>, <a href="https://publications.waset.org/abstracts/search?q=Sabra%20Habli"> Sabra Habli</a>, <a href="https://publications.waset.org/abstracts/search?q=Nejla%20Mahjoub%20Sa%C3%AFd"> Nejla Mahjoub Sa茂d</a>, <a href="https://publications.waset.org/abstracts/search?q=Herv%C3%A9%20Bournot"> Herv茅 Bournot</a>, <a href="https://publications.waset.org/abstracts/search?q=Georges%20Le%20Palec"> Georges Le Palec</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The present study treats different phenomena taking place in a configuration of air jet impinging on a flat surface in a coflow stream. A Computational Fluid Dynamics study is performed using the Reynolds-averaged Navier鈥揝tokes equations by means of the Reynolds Stress Model (RSM) second order turbulent closure model. The results include mean and turbulent velocities and quantify the large effects of the coflow stream on an impinging air jet. The study of the jet in a no-directed coflow stream shows the presence of a phenomenon of recirculation near the flat plate. The influence of the coflow velocity ratio on the behavior of an impinging plane jet was also numerically investigated. The coflow stream imposed noticeable restrictions on the spreading of the impinging jet. The results show that the coflow stream decreases considerably the entrainment of air jet. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=turbulent%20jet" title="turbulent jet">turbulent jet</a>, <a href="https://publications.waset.org/abstracts/search?q=turbulence%20models" title=" turbulence models"> turbulence models</a>, <a href="https://publications.waset.org/abstracts/search?q=coflow%20stream" title=" coflow stream"> coflow stream</a>, <a href="https://publications.waset.org/abstracts/search?q=velocity%20ratio" title=" velocity ratio"> velocity ratio</a> </p> <a href="https://publications.waset.org/abstracts/42629/numerical-study-of-an-impinging-jet-in-a-coflow-stream" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/42629.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">238</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7077</span> Comparative Study of Vertical and Horizontal Triplex Tube Latent Heat Storage Units</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Hamid%20El%20Qarnia">Hamid El Qarnia</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This study investigates the impact of the eccentricity of the central tube on the thermal and fluid characteristics of a triplex tube used in latent heat energy storage technologies. Two triplex tube orientations are considered in the proposed study: vertical and horizontal. The energy storage material, which is a phase change material (PCM), is placed in the space between the inside and outside tubes. During the thermal energy storage period, a heat transfer fluid (HTF) flows inside the two tubes, transmitting the heat to the PCM through two heat exchange surfaces instead of one heat exchange surface as it is the case for double tube heat storage systems. A CFD model is developed and validated against experimental data available in the literature. The mesh independency study is carried out to select the appropriate mesh. In addition, different time steps are examined to determine a time step ensuring accuracy of the numerical results and reduction in the computational time. The numerical model is then used to conduct numerical investigations of the thermal behavior and thermal performance of the storage unit. The effects of eccentricity of the central tube and HTF mass flow rate on thermal characteristics and performance indicators are examined for two flow arrangements: co-current and counter current flows. The results are given in terms of isotherm plots, streamlines, melting time and thermal energy storage efficiency. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=energy%20storage" title="energy storage">energy storage</a>, <a href="https://publications.waset.org/abstracts/search?q=heat%20transfer" title=" heat transfer"> heat transfer</a>, <a href="https://publications.waset.org/abstracts/search?q=melting" title=" melting"> melting</a>, <a href="https://publications.waset.org/abstracts/search?q=solidification" title=" solidification"> solidification</a> </p> <a href="https://publications.waset.org/abstracts/183782/comparative-study-of-vertical-and-horizontal-triplex-tube-latent-heat-storage-units" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/183782.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">56</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7076</span> Numerical Analysis of Supersonic Impinging Jets onto Resonance Tube</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Shinji%20Sato">Shinji Sato</a>, <a href="https://publications.waset.org/abstracts/search?q=M.%20M.%20A.%20Alam"> M. M. A. Alam</a>, <a href="https://publications.waset.org/abstracts/search?q=Manabu%20Takao"> Manabu Takao</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In recent, investigation of an unsteady flow inside the resonance tube have become a strongly motivated research field for their potential application as high-frequency actuators. By generating a shock wave inside the resonance tube, a high temperature and pressure can be achieved inside the tube, and this high temperature can also be used to ignite a jet engine. In the present research, a computational fluid dynamics (CFD) analysis was carried out to investigate the flow inside the resonance tube. The density-based solver of rhoCentralFoam in OpenFOAM was used to numerically simulate the flow. The supersonic jet that was driven by a cylindrical nozzle with a nominal exit diameter of 蠁d = 20.3 mm impinged onto the resonance tube. The jet pressure ratio was varied between 2.6 and 7.8. The gap s between the nozzle exit and tube entrance was changed between 1.5d and 3.0d. The diameter and length of the tube were taken as D = 1.25d and L=3.0D, respectively. As a result, when a supersonic jet has impinged onto the resonance tube, a compression wave was found generating inside the tube and propagating towards the tube end wall. This wave train resulted in a rise in the end wall gas temperature and pressure. While, in an outflow phase, the gas near tube enwall was found cooling back isentropically to its initial temperature. Thus, the compression waves repeated a reciprocating motion in the tube like a piston, and a fluctuation in the end wall pressures and temperatures were observed. A significant change was found in the end wall pressures and temperatures with a change of jet flow conditions. In this study, the highest temperature was confirmed at a jet pressure ratio of 4.2 and a gap of s=2.0d <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=compressible%20flow" title="compressible flow">compressible flow</a>, <a href="https://publications.waset.org/abstracts/search?q=OpenFOAM" title=" OpenFOAM"> OpenFOAM</a>, <a href="https://publications.waset.org/abstracts/search?q=oscillations" title=" oscillations"> oscillations</a>, <a href="https://publications.waset.org/abstracts/search?q=a%20resonance%20tube" title=" a resonance tube"> a resonance tube</a>, <a href="https://publications.waset.org/abstracts/search?q=shockwave" title=" shockwave"> shockwave</a> </p> <a href="https://publications.waset.org/abstracts/98109/numerical-analysis-of-supersonic-impinging-jets-onto-resonance-tube" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/98109.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">149</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7075</span> Mathematical Simulation of Performance Parameters of Pulse Detonation Engine</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Subhash%20Chander">Subhash Chander</a>, <a href="https://publications.waset.org/abstracts/search?q=Tejinder%20Kumar%20Jindal"> Tejinder Kumar Jindal</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Due to its simplicity, Pulse detonation engine technology has recently emerged as a future aerospace propulsion technology. In this paper, we studied various parameters affecting the performance of Pulse detonation engine (PDE) like tube length for proper deflagration to detonation transition (DDT), tube diameter (combustion tube), tube length, Shelkin spiral, Cell size, Equivalence ratio of fuel used etc. We have discussed various techniques for reducing the length of pulse tube by using various DDT enhancing devices. The effect of length of the tube from 40 mm to 3000 mm and diameter from 10 mm to 100 mm has been analyzed. The fuel used is C2H2 and oxidizer is O2. The results are processed in MATLAB for drawing valid conclusions. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=pulse%20detonation%20engine%20%28PDE%29" title="pulse detonation engine (PDE)">pulse detonation engine (PDE)</a>, <a href="https://publications.waset.org/abstracts/search?q=deflagration%20to%20detonation%20%28DDT%29" title=" deflagration to detonation (DDT)"> deflagration to detonation (DDT)</a>, <a href="https://publications.waset.org/abstracts/search?q=Schelkin%20spiral" title=" Schelkin spiral"> Schelkin spiral</a>, <a href="https://publications.waset.org/abstracts/search?q=cell%20size%20%28%CE%BB%29" title=" cell size (位)"> cell size (位)</a> </p> <a href="https://publications.waset.org/abstracts/20990/mathematical-simulation-of-performance-parameters-of-pulse-detonation-engine" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/20990.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">572</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7074</span> Performance Analysis of SAC-OCDMA System using Different Detectors </h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Somaya%20A.%20Abd%20El%20Mottaleb">Somaya A. Abd El Mottaleb</a>, <a href="https://publications.waset.org/abstracts/search?q=Ahmed%20Abd%20El%20Aziz"> Ahmed Abd El Aziz</a>, <a href="https://publications.waset.org/abstracts/search?q=Heba%20A.%20Fayed"> Heba A. Fayed</a>, <a href="https://publications.waset.org/abstracts/search?q=Moustafa%20H.%20Aly">Moustafa H. Aly</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, we present the performance of spectral amplitude coding optical code division multiple access using different detectors at different transmission distances using single photodiode detection technique. Modified double weight codes are used as signature codes. Simulation results show that the system using avalanche photo detector can move distance longer than that using positive intrinsic negative photo detector. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=avalanche%20photodiode" title="avalanche photodiode">avalanche photodiode</a>, <a href="https://publications.waset.org/abstracts/search?q=modified%20double%20weight" title=" modified double weight"> modified double weight</a>, <a href="https://publications.waset.org/abstracts/search?q=multiple%20access%20technique" title=" multiple access technique"> multiple access technique</a>, <a href="https://publications.waset.org/abstracts/search?q=single%20photodiode." title=" single photodiode. "> single photodiode. </a> </p> <a href="https://publications.waset.org/abstracts/12035/performance-analysis-of-sac-ocdma-system-using-different-detectors" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/12035.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">605</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7073</span> Design Optimization and Thermoacoustic Analysis of Pulse Tube Cryocooler Components</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=K.%20Aravinth">K. Aravinth</a>, <a href="https://publications.waset.org/abstracts/search?q=C.%20T.%20Vignesh"> C. T. Vignesh</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The usage of pulse tube cryocoolers is significantly increased mainly due to the advantage of the absence of moving parts. The underlying idea of this project is to optimize the design of pulse tube, regenerator, a resonator in cryocooler and analyzing the thermo-acoustic oscillations with respect to the design parameters. Computational Fluid Dynamic (CFD) model with time-dependent validation is done to predict its performance. The continuity, momentum, and energy equations are solved for various porous media regions. The effect of changing the geometries and orientation will be validated and investigated in performance. The pressure, temperature and velocity fields in the regenerator and pulse tube are evaluated. This optimized design performance results will be compared with the existing pulse tube cryocooler design. The sinusoidal behavior of cryocooler in acoustic streaming patterns in pulse tube cryocooler will also be evaluated. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=acoustics" title="acoustics">acoustics</a>, <a href="https://publications.waset.org/abstracts/search?q=cryogenics" title=" cryogenics"> cryogenics</a>, <a href="https://publications.waset.org/abstracts/search?q=design" title=" design"> design</a>, <a href="https://publications.waset.org/abstracts/search?q=optimization" title=" optimization"> optimization</a> </p> <a href="https://publications.waset.org/abstracts/82751/design-optimization-and-thermoacoustic-analysis-of-pulse-tube-cryocooler-components" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/82751.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">175</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7072</span> Brazilian Environmental Public Policies Analysis</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Estela%20Macedo%20Alves">Estela Macedo Alves</a> </p> <p class="card-text"><strong>Abstract:</strong></p> This paper is an overview on public policy analysis focused on the study of Brazilian public policy making process. The methodology is based on the review of some theories on the subject, linking them to Brazilian reality. The study presents basic policy analysis concepts, such as policy, polity and politics. It is emphasized John Kingdon's Multiple Stream Model, because of its clarifying aspects concerning public policies formulation process in democratic countries. In this path it was possible to establish interpretations on environmental public policies in Brazil and understand its methods, instead of presenting only a case study. At the end, it is possible to connect theory with Brazilian reality, identifying negative and positive points of its political processes and structure. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=Brazilian%20policies" title="Brazilian policies">Brazilian policies</a>, <a href="https://publications.waset.org/abstracts/search?q=environmental%20public%20policy" title=" environmental public policy"> environmental public policy</a>, <a href="https://publications.waset.org/abstracts/search?q=multiple%20stream%20model" title=" multiple stream model"> multiple stream model</a>, <a href="https://publications.waset.org/abstracts/search?q=public%20policy%20analysis" title=" public policy analysis"> public policy analysis</a> </p> <a href="https://publications.waset.org/abstracts/7839/brazilian-environmental-public-policies-analysis" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/7839.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">407</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7071</span> Fluid Flow in Roughened Square Tube for Internal Blade Cooling</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=M.%20H.%20Alhajeri">M. H. Alhajeri</a>, <a href="https://publications.waset.org/abstracts/search?q=Hamad%20M.%20Alhajeri"> Hamad M. Alhajeri</a>, <a href="https://publications.waset.org/abstracts/search?q=A.%20H.%20Alenezi"> A. H. Alenezi</a>, <a href="https://publications.waset.org/abstracts/search?q=Abdulrahman%20Almutairi"> Abdulrahman Almutairi</a>, <a href="https://publications.waset.org/abstracts/search?q=Ayedh%20Alajmi"> Ayedh Alajmi</a> </p> <p class="card-text"><strong>Abstract:</strong></p> A computational investigation has been undertaken to study fluid flow through roughened tube with turbulators. Such flows are of particular interest in cooling internally high pressure turbine blades. Turbulators are fixed in each side of the passage (tube) to promote turbulence and enhance heat transfer. The tube had an aspect ratio of 1 and the position of the ribs closest to the bend are at 0.45d from the entrance and exit of the bend. The aim of this study is to examine the tube roughened by turbulator by studying some flow parameters upstream and downstream of the turbulator. It is cleared that the eddies sizes are decreased downstream in the first two turbulators and increased after the turbulators increases the turbulence in the tube and enhanced the heat transfer in the blade. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=fluid%20flow" title="fluid flow">fluid flow</a>, <a href="https://publications.waset.org/abstracts/search?q=turbulator" title=" turbulator"> turbulator</a>, <a href="https://publications.waset.org/abstracts/search?q=computation" title=" computation"> computation</a>, <a href="https://publications.waset.org/abstracts/search?q=blade" title=" blade"> blade</a> </p> <a href="https://publications.waset.org/abstracts/74458/fluid-flow-in-roughened-square-tube-for-internal-blade-cooling" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/74458.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">426</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7070</span> Predicting the Turbulence Intensity, Excess Energy Available and Potential Power Generated by Building Mounted Wind Turbines over Four Major UK City</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Emejeamara%20Francis">Emejeamara Francis</a> </p> <p class="card-text"><strong>Abstract:</strong></p> The future of potentials wind energy applications within suburban/urban areas are currently faced with various problems. These include insufficient assessment of urban wind resource, and the effectiveness of commercial gust control solutions as well as unavailability of effective and cheaper valuable tools for scoping the potentials of urban wind applications within built-up environments. In order to achieve effective assessment of the potentials of urban wind installations, an estimation of the total energy that would be available to them were effective control systems to be used, and evaluating the potential power to be generated by the wind system is required. This paper presents a methodology of predicting the power generated by a wind system operating within an urban wind resource. This method was developed by using high temporal resolution wind measurements from eight potential sites within the urban and suburban environment as inputs to a vertical axis wind turbine multiple stream tube model. A relationship between the unsteady performance coefficient obtained from the stream tube model results and turbulence intensity was demonstrated. Hence, an analytical methodology for estimating the unsteady power coefficient at a potential turbine site is proposed. This is combined with analytical models that were developed to predict the wind speed and the excess energy (EEC) available in estimating the potential power generated by wind systems at different heights within a built environment. Estimates of turbulence intensities, wind speed, EEC and turbine performance based on the current methodology allow a more complete assessment of available wind resource and potential urban wind projects. This methodology is applied to four major UK cities namely Leeds, Manchester, London and Edinburgh and the potential to map the turbine performance at different heights within a typical urban city is demonstrated. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=small-scale%20wind" title="small-scale wind">small-scale wind</a>, <a href="https://publications.waset.org/abstracts/search?q=turbine%20power" title=" turbine power"> turbine power</a>, <a href="https://publications.waset.org/abstracts/search?q=urban%20wind%20energy" title=" urban wind energy"> urban wind energy</a>, <a href="https://publications.waset.org/abstracts/search?q=turbulence%20intensity" title=" turbulence intensity"> turbulence intensity</a>, <a href="https://publications.waset.org/abstracts/search?q=excess%20energy%20content" title=" excess energy content"> excess energy content</a> </p> <a href="https://publications.waset.org/abstracts/49803/predicting-the-turbulence-intensity-excess-energy-available-and-potential-power-generated-by-building-mounted-wind-turbines-over-four-major-uk-city" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/49803.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">277</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7069</span> UML Model for Double-Loop Control Self-Adaptive Braking System</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Heung%20Sun%20Yoon">Heung Sun Yoon</a>, <a href="https://publications.waset.org/abstracts/search?q=Jong%20Tae%20Kim"> Jong Tae Kim</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, we present an activity diagram model for double-loop control self-adaptive braking system. Since activity diagram helps to improve visibility of self-adaption, we can easily find where improvement is needed on double-loop control. Double-loop control is adopted since the design conditions and actual conditions can be different. The system is reconfigured in runtime by using double-loop control. We simulated to verify and validate our model by using MATLAB. We compared single-loop control model with double-loop control model. Simulation results show that double-loop control provides more consistent brake power control than single-loop control. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=activity%20diagram" title="activity diagram">activity diagram</a>, <a href="https://publications.waset.org/abstracts/search?q=automotive" title=" automotive"> automotive</a>, <a href="https://publications.waset.org/abstracts/search?q=braking%20system" title=" braking system"> braking system</a>, <a href="https://publications.waset.org/abstracts/search?q=double-loop" title=" double-loop"> double-loop</a>, <a href="https://publications.waset.org/abstracts/search?q=self-adaptive" title=" self-adaptive"> self-adaptive</a>, <a href="https://publications.waset.org/abstracts/search?q=UML" title=" UML"> UML</a>, <a href="https://publications.waset.org/abstracts/search?q=vehicle" title=" vehicle"> vehicle</a> </p> <a href="https://publications.waset.org/abstracts/5691/uml-model-for-double-loop-control-self-adaptive-braking-system" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/5691.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">416</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7068</span> Unsteady Characteristics Investigation on the Precessing Vortex Breakdown and Energy Separation in a Vortex Tube</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Xiangji%20Guo">Xiangji Guo</a>, <a href="https://publications.waset.org/abstracts/search?q=Bo%20Zhang"> Bo Zhang</a> </p> <p class="card-text"><strong>Abstract:</strong></p> In this paper, the phenomenon of vortex breakdown in a vortex tube was analyzed within the scope of unsteady character in swirl flows. A 3-D Unsteady Reynolds-averaged Navier鈥揝tokes (URANS) closed by the Reynolds Stress Model (RSM) was adopted to simulate the large-scale vortex structure in vortex tube, and the numerical model was verified by the steady results. The swirl number was calculated for the vortex tube and the flow field was classed as strong swirl flow. According to the results, a time-dependent spiral flow field gyrates around a central recirculation zone which is precessing around the axis of the tube, and manifests the flow structure is the spiral type (S-type) vortex breakdown. The vortex breakdown is crucial for the formation of the central recirculation zone (CRZ), a further discussion was about the affection on CRZ with the different external conditions of vortex tube, the study on the unsteady characters was expected to hope to design of vortex tube and analyze the energy separation effect. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=vortex%20tube" title="vortex tube">vortex tube</a>, <a href="https://publications.waset.org/abstracts/search?q=vortex%20breakdown" title=" vortex breakdown"> vortex breakdown</a>, <a href="https://publications.waset.org/abstracts/search?q=central%20recirculation%20zone" title=" central recirculation zone"> central recirculation zone</a>, <a href="https://publications.waset.org/abstracts/search?q=unsteady" title=" unsteady"> unsteady</a>, <a href="https://publications.waset.org/abstracts/search?q=energy%20separation" title=" energy separation"> energy separation</a> </p> <a href="https://publications.waset.org/abstracts/52531/unsteady-characteristics-investigation-on-the-precessing-vortex-breakdown-and-energy-separation-in-a-vortex-tube" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/52531.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">318</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7067</span> Simulation of Internal Flow Field of Pitot-Tube Jet Pump</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Iqra%20Noor">Iqra Noor</a>, <a href="https://publications.waset.org/abstracts/search?q=Ihtzaz%20Qamar"> Ihtzaz Qamar</a> </p> <p class="card-text"><strong>Abstract:</strong></p> Pitot-tube Jet pump, single-stage pump with low flow rate and high head, consists of a radial impeller that feeds water to rotating cavity. Water then enters stationary pitot-tube collector (diffuser), which discharges to the outside. By means of ANSYS Fluent 15.0, the internal flow characteristics for Pitot-tube Jet pump with standard pitot and curved pitot are studied. Under design condition, realizable k-e turbulence model and SIMPLEC algorithm are used to calculate 3D flow field inside both pumps. The simulation results reveal that energy is imparted to the flow by impeller and inside the rotor, forced vortex type flow is observed. Total pressure decreases inside pitot-tube whereas static pressure increases. Changing pitot-tube from standard to curved shape results in minimum flow circulation inside pitot-tube and leads to a higher pump performance. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=CFD" title="CFD">CFD</a>, <a href="https://publications.waset.org/abstracts/search?q=flow%20circulation" title=" flow circulation"> flow circulation</a>, <a href="https://publications.waset.org/abstracts/search?q=high%20pressure%20pump" title=" high pressure pump"> high pressure pump</a>, <a href="https://publications.waset.org/abstracts/search?q=impeller" title=" impeller"> impeller</a>, <a href="https://publications.waset.org/abstracts/search?q=internal%20flow" title=" internal flow"> internal flow</a>, <a href="https://publications.waset.org/abstracts/search?q=pickup%20tube%20pump" title=" pickup tube pump"> pickup tube pump</a>, <a href="https://publications.waset.org/abstracts/search?q=rectangle%20channels" title=" rectangle channels"> rectangle channels</a>, <a href="https://publications.waset.org/abstracts/search?q=rotating%20casing" title=" rotating casing"> rotating casing</a>, <a href="https://publications.waset.org/abstracts/search?q=turbulence" title=" turbulence"> turbulence</a> </p> <a href="https://publications.waset.org/abstracts/132118/simulation-of-internal-flow-field-of-pitot-tube-jet-pump" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/132118.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">160</span> </span> </div> </div> <div class="card paper-listing mb-3 mt-3"> <h5 class="card-header" style="font-size:.9rem"><span class="badge badge-info">7066</span> Effects of Using Clinical Guidelines for Feeding through a Gastrostomy Tube in Critically ill Surgical Patients Songkla Hospital Thailand</h5> <div class="card-body"> <p class="card-text"><strong>Authors:</strong> <a href="https://publications.waset.org/abstracts/search?q=Siriporn%20Sikkaphun">Siriporn Sikkaphun </a> </p> <p class="card-text"><strong>Abstract:</strong></p> Food is essential for living, and receiving correct, suitable, and adequate food is advantageous to the body, especially for patients because it can enable good recovery. Feeding through a gastrostomy tube is one useful way that is widely used because it is easy, convenient, and economical.To compare the effectiveness of using the clinical guidelines for feeding through a gastrostomy tube in critically ill surgical patients.This is a pre-post quasi-experimental study on 15 critically ill surgical or accident patients who needed intubation and the gastrostomy tube from August 2011 to November 2012. The data were collected using the guidelines, and an evaluation form for effectiveness of guidelines for feeding through a gastrostomy tube in critically ill surgical patients. After using the guidelines for feeding through a gastrostomy tube in critically ill surgical patients, it was found that The average number of days from the admission date to the day the patients received food through the G-tube significantly reduced at the level .05. The number of personnel who practiced nursing activities correctly and suitably for patients with complications during feeding significantly increased at the level .05.The number of patients receiving energy to the target level significantly increased at the level .05. The results of this study indicated that the use of the guidelines for feeding through a gastrostomy tube in critically ill surgical patients was feasible in practice, and the outcomes were beneficial to the patients. <p class="card-text"><strong>Keywords:</strong> <a href="https://publications.waset.org/abstracts/search?q=clinical%20guidelines" title="clinical guidelines">clinical guidelines</a>, <a href="https://publications.waset.org/abstracts/search?q=feeding" title=" feeding"> feeding</a>, <a href="https://publications.waset.org/abstracts/search?q=gastrostomy%20tube" title=" gastrostomy tube"> gastrostomy tube</a>, <a href="https://publications.waset.org/abstracts/search?q=critically%20ill" title=" critically ill"> critically ill</a>, <a href="https://publications.waset.org/abstracts/search?q=surgical%20patients" title=" surgical patients "> surgical patients </a> </p> <a href="https://publications.waset.org/abstracts/23509/effects-of-using-clinical-guidelines-for-feeding-through-a-gastrostomy-tube-in-critically-ill-surgical-patients-songkla-hospital-thailand" class="btn btn-primary btn-sm">Procedia</a> <a href="https://publications.waset.org/abstracts/23509.pdf" target="_blank" class="btn btn-primary btn-sm">PDF</a> <span class="bg-info text-light px-1 py-1 float-right rounded"> Downloads <span class="badge badge-light">323</span> </span> </div> </div> <ul class="pagination"> <li class="page-item disabled"><span class="page-link">&lsaquo;</span></li> <li class="page-item active"><span class="page-link">1</span></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=double%20multiple%20stream%20tube&page=2">2</a></li> <li class="page-item"><a class="page-link" href="https://publications.waset.org/abstracts/search?q=double%20multiple%20stream%20tube&page=3">3</a></li> <li class="page-item"><a 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