熱泳效應在旋轉圓盤上對微粒附著率之研究

Thermophoretic Effect on Particle Deposition from a Rotating Disk Flow

詹文斌(W. B. Jame) ； 蔡瑞益(R. Tsai) ； 張永鵬(Y. P. Chang) ； 林德光(T. K. Lin)

《中原學報》 31卷3期 (2003/09) Pp. 189-196

https://doi.org/10.6358/JCYU.200309.0189

摘要

本文研究氣膠微粒流經一旋轉圓盤之溫度分佈和微粒附著沈積速度。空氣流體狀態設爲穩態不可壓縮之層流流場，旋轉圓盤造成之不等溫對流流場將對氣膠微粒產生熱泳效應。微粒之沈積效應包含對流、布朗擴散和熱泳傳輸機制。計算過程以計算流體力學套裝軟體FIDAP作數値計算，再以半經驗方法推導，微粒沈積速度與熱泳速度之關係式爲V(下标 d)/V(下标 T)=A(ω)exp(-KP(下标 r)(△T/T(下标 ∞))，其中當自由流速度15cm/s時，A(ω)=0.141+3.2×10^(-3)ω。另外，結果顯示微粒附著沈積速度隨著旋轉圓盤轉速、自由速度和溫度差之增加而增加。

關鍵字

熱泳效應 ； 微粒沈積速度 ； 布朗擴散 ； 圓盤轉速

並列摘要

The thermophoretic effect on deposition of aerosol particles from the air flow toward a rotating disk is proposed. The flow was modeled as a three-dimensional, steady, incompressible and laminar flow. The deposition mechanisms included Brownian diffusion, convection and thermophoresis. The flow and temperature fields were solved using the CFD software FIDAP. As the free-stream velocity is 15cm/s,the relation between the particle deposition velocity and thermophoretic velocity is fitted to bean empirical correlation, V(subscript d)/V(subscript T)=A(ω)exp(-KP(subscript r)(△T/T(subscript ∞))),where A(ω)=0.141+3.2×10^(-3)ω.The results also showed that the deposition velocity increased with an increase in disk rotating velocity, free-stream velocity, and temperature difference.

並列關鍵字

thermophoretic effect ； particle deposition velocity ； Brownian diffusion ； disk rotating velocity