Combined Heat and Mass Transfer by Mixed Convection in Stagnation Flow Adjacent to a Vertical Permeable Plate

混合對流停滯流動流經－垂直可穿透性平板之熱傳與質傳

易國安(Kuo-Ann Yih)

《中國航空太空學會學刊》 32卷2期 (2000/06) Pp. 179-184

https://doi.org/10.6124/TAASRC.200006_32(2).09

摘要

本文以一數值方法來分析混合對流停滯流動流經－垂直可穿透性平板之熱傳與質傳。垂直平被表面為線性壁溫度(LWT)與線性壁濃度(LWC)。非線性邊界層方程式經轉換成常微分方程式，吾人以一有限差分方法（凱勒盒子法）解之。數值計算結果主要顯示諸參數對局部磨擦係數、局部Nusselt數和局部Sherwood數。對熱輔助（阻礙）流情況，增加史密特數Sc減少（增加）局部磨擦係數和局部Nusselt數。皮之，局部Sherwood數隨史密特數增加而增大。增加吸／噴流參數f(下标 w)、浮力參數Gr(下标 x)/Re(上标 2 下标 x)和浮力比N會增大局部磨擦係敏、局部熱傳與質傳率。

關鍵字

熱傳與質傳 ； 混合對流 ； 停滯流動 ； 垂直可穿透性平板

並列摘要

The steady two-dimensional laminar combined heat and mass transfer by mixed convection in stagnation flow adjacent to a vertical permeable flat surface is numerically analyzed. The vertical flat surface is maintained at linear wall temperature (LWT) and linear wall concentration (LWC). The nonlinear boundary-layer equations are transformed and the resulting ordinary differential equations are solved by an implicit finite difference scheme (Keller box method). Numerical results for the local friction coefficient, the local Nusselt number and the local Sherwood number are presented for various parameters. For the thermally assisting (opposing) flow, increasing the Schmidt number decreases (increases) the local friction coefficient and the local Nusselt number. On the other hand, the local Sherwood number enhances as the Schmidt number increases. Increasing the suction/blowing parameter f(subscript W), the buoyancy parameter Gr(subscript x)/Re(superscript 2 subscript x) and the buoyancy ratio N increases the local friction coefficient, the local heat and mass transfer rates.

並列關鍵字

Heat and Mass Transfer ； Mixed Convection ； Stagnation Flow ； Vertical Permeable Plate