Fluid Flow and Heat Transfer of Mixed Convection and Its Application to Thin Film Formation by CVD

混合对流流体流动和传热及其在CVD薄膜形成中的应用

基本信息

批准号：
18560198
负责人：
KITAMURA Kenzo
金额：
$ 2.37万
依托单位：
Toyohashi University of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18560198/
关键词：
Heat Transfer Convective Heat Transfer Mixed Convection Forced Convection Natural Convection Upward-Facing Plate Stagnation Flow Buoyancy Effect

项目摘要

Fluid flow and heat transfer of mixed convection over upward-facing horizontal heated plates placed in a uniform downward flow of forced convection were investigated experimentally. The experiments were carried out with air and with the test plates of 50 and 100mm wide, which were heated with uniform heat flux. The Reynolds and modified Rayleigh numbers ranged as: Rew =37-2000 and Raw^*=6.2x10^4-5.3x×10^7.The flow fields over heated plates were visualized with smoke. The results showed that the laminar wedge flow from the center to the edges of the plate appears when the heat fluxes are small, while that the flow turns its direction from the edges to the center with increasing the heat flux, and, finally, the flow detaches from the center of the plate as a buoyant plume when the heat fluxes are high enough. The local heat transfer coefficients from the plates were also measured. The results showed that the coefficients under the fixed velocity of the forced flow are increased monotonously with the heat fluxes. It was also found that the overall Nusselt numbers of the plates, Nun, were predicted well with the non-dimensional parameter, (GrW^*/d/Num Rew^2.5), where Grw^* stands for the Grashof numbers. Moreover, the parameter well classify the regions of the forced, mixed and natural convection, and the mixed convection region is determined as : 0.3< (Grw^*/Num Rew^<2.5>) <15

经过实验研究了将混合连接在向上的水平加热板上的混合连接的热传递，该水平加热板在强制会议的均匀向下流动中进行了实验研究。用空气和50和100mm宽的测试板进行实验，并用均匀的热通量加热。雷诺和修改后的雷利数范围为：rew = 37-2000和RAW^*= 6.2x10^4-5.3x×10^7.加热板上的流场用烟雾可视化。结果表明，当热通量较小时，层状楔流从中心到板的边缘出现，而流量则随着热通量增加而将其方向从边缘转向中心，最后，当热通量足够高时，流量从板的中心偏离了板的中心。还测量了来自板的局部传热系数。结果表明，强制流动速度下的核心随热通量单调增加。还发现，板的总体数字是Nun的总数，可以很好地预测到非二维参数（grw^*/d/d/num rew^2.5），其中grw^*代表Grashof数字。此外，参数很好地对强制，混合和自然连接的区域进行了很好的分类，并且混合连接区域的确定为：0.3 <（grw^*/num rew^<2.5>）<15