標題: Delayed onset of return flow by substrate inclination in model horizontal longitudinal MOCVD processes
作者: Kuo, WS
Wang, CY
Tuh, JL
Lin, TF
機械工程學系
Department of Mechanical Engineering
關鍵字: convection;fluid flows;metalorganic chemical vapor deposition
公開日期: 15-一月-2005
摘要: In this study an experimental flow visualization is carried out to investigate how the substrate inclination affects the buoyancy-induced return flow structure in mixed convection of gas in a horizontal rectangular duct. The return flow is driven by a heated circular disk embedded in the bottom plate of the duct. simulating that in a horizontal longitudinal MOCVD reactor. Specifically, the bottom plate of the duct is inclined so that the gas flow in the duct is accelerated, causing the buoyancy-to-inertia ratio to decrease in the main flow direction. In the experiment. the Reynolds and Rayleigh numbers of the flow at the duct inlet are respectively varied from 3.7 to 79.7 and from 90,40 to 24,000 for the inclined angle of the bottom plate fixed at 0degrees, 0.34degrees and 0.97degrees. Particular attention is paid to delineating the spatial changes of the return flow structure with the plate inclination angle and to how the bottom plate tilting possibly, suppresses and stabilizes the flow. The results show a substantial delay in the onset of the return flow and the effctive suppression of the buoyancy-driven unstable vortex flow by the bottom plate inclination. Besides, the bottom, plate inclination can effectively weaken the return flow at slightly higher Reynolds numbers. An empirical equation is provided to correlate the present data for the onset of the return flow in the duct with its bottom inclined at 0: and 0.97degrees. (C) 2004 Elsevier B.V. All rights reserved.
URI: http://dx.doi.org/10.1016/j.jcrysgro.2004.09.097
http://hdl.handle.net/11536/24150
ISSN: 0022-0248
DOI: 10.1016/j.jcrysgro.2004.09.097
期刊: JOURNAL OF CRYSTAL GROWTH
Volume: 274
Issue: 1-2
起始頁: 265
結束頁: 280
顯示於類別:期刊論文


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  1. 000226340900038.pdf