Surface Rejuvenation Model分析紊流微粒傳遞

Surface Rejuvenation Model for Analysis of Turbulent Particle Transports

劉建宏(Jian-Hong Liou)

指導教授 ： 邱明志

國立虎尾科技大學/工程學院/機械與機電工程研究所/碩士(2008年)

https://doi.org/10.6827/NFU.2008.00020

摘要

基於surface rejuvenation model，可獲得黏滯子層在壁面發展之平均成長週期，並延伸此模式來得到thermophoresis與turbophoresis在非等溫紊流邊界流動場之相互作用對微粒子傳遞的影響。
為了簡化微粒子在單一渦流的停滯時間內之對流漂移速度的計算，藉由重建微粒連續方程式的微粒總通量，得到微粒子分離濃度場動量方程式的組成分量。此方法的建立是基於對擴散機制與慣性機制的適當估算，並提出一解析解，使微粒子的濃度發展預測量與微粒子的擴散通量和對流通量結合。藉由所獲得之解析解估算在平均子層成長週期間的微粒沉澱率，並以曲線描繪此沉澱率與停滯時間的相對關係，其結果與實驗量測數據吻合。

關鍵字

氣懸微粒 ； 紊流 ； 熱泳

並列摘要

Based on the surface rejuvenation model, the average grown period relying on a more detailed picture of the periodic sublayer development in the wall region has been obtained. Attempt is to extend this model to capture the interaction effects of thermophoresis and turbophoresis on the particle transport in the non-isothermal turbulent boundary flow field.
In order to simplify the estimate of convective drift velocity of particles within the residence time of a single eddy, the detachment of concentration dependence components from the particle momentum equation is reached by reconstructing the overall particle flux of the particle continuity equation. This procedure establishes a basis for the appropriate estimates of the diffusion and inertial mechanisms, and provides an analytical solution to connect the quantitative predictions of particle concentration development with the diffusive and convective flux of particles.
During the average growth period of viscous sublayer, the physical trend of the modeling parameters has been quantitatively revealed in some extent. In comparison with available particle transport data, the calculated results of the particle deposition rate for the different ranges of the particle relaxation time are in general agreement.

並列關鍵字

aerosol ； turbulence ； thermophoresis

參考文獻

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