兩相紊態混合層流場模擬中穩態假設顆粒阻力係數的檢視

Re-Examination of Steady State Assumption of Drag Coefficient in Calculation of Two-Phase Turbulent Mixing-Layer Flow

張克勤(Keh-Chin Chang) ； 楊進成(Jinn-Cheng Yang)

《中國航空太空學會學刊》 29卷1期 (1997/03) Pp. 91-100

https://doi.org/10.6124/TAASRC.199703_29(1).10

摘要

本研究採用SSF(stochastic separated flow)模式，加上解顆粒紊流動能的方程式，來模擬平面、紊態之噴霧混合層流。以往之研究，對於顆粒的阻力係數只考慮假設爲穩態的阻力係數，使得其顆拉紊流動能的數值計算結果與實驗值間出現相當的差距，本研究針對此項缺失加以改善，考慮暫態的阻力係數。結果顯示，此舉將使得所解得顆粒的紊流動能與實驗值更接近。

關鍵字

兩相流 ； 噴霧 ； 阻力係數

並列摘要

This work employs the SSF (stochastic separated flow) model coupling with the Lagrangian equation of turbulent kinetic energy of the dispersed phase in the calculation of a planar, turbulent mixing layer loaded with a polydispersed water spray. It is found that the use of steady-state expression of drag coefficient introduced some errors in prediction of turbulent kinetic energy of the dispersed phase. To overcome the aformentioned defect, the unsteady-state expression of drag coefficient proposed by Sano (1981) is used in the work. It shows that the prediction of the dispersed-phase turbulent kinetic energy is indeed improved as compared to the experimental data.

並列關鍵字

Two-phase flow ； spray ； drag coefficient