Volume 8B: Heat Transfer and Thermal Engineering最新文献_第6页

Heat Transfer Augmentation From Extended Surface Using Dimples 利用凹痕从扩展表面增强传热

Volume 8B: Heat Transfer and Thermal Engineering Pub Date : 2018-11-09 DOI: 10.1115/IMECE2018-87345

Jay D. Mehta, Fay N. Colah, Anurag P. Rao, Vineeta P. Pendse, Vyankatesh Bagal, Kevin P. Ajmera

引用次数: 0

Flow Characteristics of Nitrogen (N2) in Micro-Channels of Printed Circuit Heat Exchanger (PCHE) 氮气(N2)在印刷电路换热器(PCHE)微通道中的流动特性

Volume 8B: Heat Transfer and Thermal Engineering Pub Date : 2018-11-09 DOI: 10.1115/IMECE2018-86617

Jeong-heon Shin, S. Yoon, J. Choi

{"title":"Flow Characteristics of Nitrogen (N2) in Micro-Channels of Printed Circuit Heat Exchanger (PCHE)","authors":"Jeong-heon Shin, S. Yoon, J. Choi","doi":"10.1115/IMECE2018-86617","DOIUrl":"https://doi.org/10.1115/IMECE2018-86617","url":null,"abstract":"Experiment and simulation studies were performed to investigate the flow characteristics of pressure-driven Nitrogen flow in the micro-channels of Printed Circuit Heat Exchanger (PCHE). The core of the PCHE was made using diffusion bonding method with ten stainless steel 316L plates, where hemispherical 1 mm in diameter channels were chemically etched. On one of the plates, four-teen more channels, 1 mm in diameter, were milled to make pressure taps to measure local pressure drops. Then, one inlet tube and four-teen tubes for pressure tabs were attached by welding on the top and sides of PCHE core, respectively. The PCHE was connected to Nitrogen tank with pressure regulator, Coriolis flowmeter and differential pressure gauge, and data was acquired with DAQ system.\u0000 By varying the velocity of Nitrogen gas from 1 to 35 m/s, differential pressure drops were measured between two different locations. The local pressure drops were analyzed theoretically and pressure loss coefficients could be calculated in straight and serpentine channels, respectively. In addition, simulation work using ANSYS Fluent was also performed to understand flow characteristics especially at corners of channels.","PeriodicalId":307820,"journal":{"name":"Volume 8B: Heat Transfer and Thermal Engineering","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121324984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Investigation on Simultaneous Effects of Surface Roughness and Variable Properties on Laminar Flow in Annular Tubes 表面粗糙度和变性能对环管内层流同时影响的数值研究

Volume 8B: Heat Transfer and Thermal Engineering Pub Date : 2018-11-09 DOI: 10.1115/IMECE2018-88288

M. Heydari, A. Bagheri, Hamid Sadat, H. Bostanci, S. Nasrazadani

引用次数: 0

Three-Tier Impingement Cooling Design for Gas Turbine Blade Trailing Edge 燃气轮机叶片后缘三层冲击冷却设计

Volume 8B: Heat Transfer and Thermal Engineering Pub Date : 2018-11-09 DOI: 10.1115/IMECE2018-86430

K. Ramakrishnan, Prashant Singh, S. Ekkad

{"title":"Three-Tier Impingement Cooling Design for Gas Turbine Blade Trailing Edge","authors":"K. Ramakrishnan, Prashant Singh, S. Ekkad","doi":"10.1115/IMECE2018-86430","DOIUrl":"https://doi.org/10.1115/IMECE2018-86430","url":null,"abstract":"Gas turbine blades are subjected to elevated heat loads due to highly turbulent hot gases exiting the combustor section. Several internal and external cooling techniques are used to protect the blades from such hostile environment. Trailing edge of a turbine blade is usually cooled with array of staggered cylindrical pins, which connects the pressure and suction side internal walls and hence provide improved structural integrity. However, the heat transfer enhancement levels for array of pin-fins is generally lower than jet impingement and ribbed channels. In this study, we present a three-tier impingement cooling design for blade trailing-edge and part of mid-chord region. In this design, pressure and suction side internal walls are subjected to oblique jet impingement. Three different configurations have been studied where we have systematically varied the jet diameters and number of jets in an array for different tiers. Numerical simulations have been carried out for different flow conditions, which corresponds to Reynolds numbers (based on 1st-passage jet diameter) ranging between 3000 and 46000. First two plenums had high levels of heat transfer due to oblique jet impingement, where the suction side internal wall representative surface, had higher heat transfer compared to the pressure side internal wall. Third tier had the lowest heat transfer due to triangle-like configuration where jets were almost parallel to pressure and suction side surfaces, and hence their effectiveness was lower than the oblique jet impingement in upstream two tiers.","PeriodicalId":307820,"journal":{"name":"Volume 8B: Heat Transfer and Thermal Engineering","volume":"79 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125325617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1