Effects of Jet Diameter and Surface Roughness on Internal Cooling With Single Array of Jets

Author:

Miller Nicholas1,Siw Sin Chien1,Chyu Minking K.1,Alvin Mary Anne2

Affiliation:

1. University of Pittsburgh, Pittsburgh, PA

2. U.S. DOE National Energy Technology Laboratory, Pittsburgh, PA

Abstract

The current study focused on the effects of varying jet diameter and surface roughness on the target plate from jet impingement. A single row of five jets, plenum fed, expels air onto the flat target surface and the spent air is constrained to exit in only one direction, causing the jets to encounter maximum cross-flow. Baseline jet plates were equipped with pressure taps, one for each jet, to determine flow. The initial parameters, diameter D, height to diameter H/D, and jet spacing to diameter S/D is 9.53 mm (0.375 in), 2 and 4 respectively. Upon defining the optimum array of jet diameters, three test cases will be conducted using different surface features, 90 degree ribs, chevrons and X-shaped ribs on the target plate to further enhance the heat transfer performance of the jet impingement. The parameters, width W and height H, for the surface features will be set constant at 3.18 mm (0.125 in). The Reynolds number, Re, in this experimental study ranged from 50,000 to 80,000. A transient liquid crystal technique is employed in this study to determine the local and average heat transfer coefficient distribution on the target plate. The baseline tests revealed that the heat transfer is more predominate in the upstream jets impingement zones, however, by varying the diameters the heat transfer is more uniformly distributed downstream. The results also revealed that the rib-turbulators, especially X-shaped ribs, can further enhance heat transfer enhancement in the downstream jets where crossflow can affect impingement.

Publisher

American Society of Mechanical Engineers

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3