Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
669072 | International Journal of Thermal Sciences | 2016 | 17 Pages |
Abstract
A Computational study was conducted to investigate the convective heat transfer characteristics by a row of tab-excited air jets impingement on a wedge-shaped concave surface having larger curvature than semi-circular concave surface. The geometric effects, including the tab number and tab penetration ratio, as well as the offset-jets arrangement, on the impinging jet flow and heat transfer behaviors are analyzed under several non-dimensional jet-to-leading edge distances (6, 9, 12) and the jet Reynolds numbers ranging from 6900 to 26,100. The results show that both the jet offset-arrangement and tab-excitation are proved to be capable of improving the convective heat transfer in the vicinity of jet impingement region. Either for the conventional round jet or tab-excited jet, it appears that an optimum non-dimensional jet-offset distance is about 1.5. The heat transfer enhancement is improved as the increase of tab number (ranging from 4 to 8), as well as tab penetration ratio (ranging from 0.13 to 0.25). The influence intensity of non-dimensional jet-offset distance on the convective heat transfer inside a concave cavity is more significant for the tab-excited jet impingement than that for the conventional round jet impingement. In general, the effects of jet offset-arrangement and tab-excitation on the jet impingement heat transfer enhancement behave more significant under larger jet Reynolds number as well as smaller impingement distance.
Related Topics
Physical Sciences and Engineering
Chemical Engineering
Fluid Flow and Transfer Processes
Authors
Tao Guan, Jing-zhou Zhang, Yong Shan,