化工学报 ›› 2009, Vol. 60 ›› Issue (1): 157-162.

• 过程系统工程 • 上一篇    下一篇

喷射器内湍流混合的多尺度模拟

毕荣山,马连湘,程华农,谭心舜,郑世清   

  1. 青岛科技大学计算机与化工研究所;青岛科技大学机电工程学院
  • 出版日期:2009-01-05 发布日期:2009-01-05

Multi-scale simulation of turbulent mixing in ejector

BI Rongshan, MA Lianxiang, CHENG Huanong, TAN Xinshun, ZHENG Shiqing   

  • Online:2009-01-05 Published:2009-01-05

摘要:

利用宏观混合分数方差和微观混合分数方差定量表征宏观混合和微观混合状态,对喷射器内的湍流混合进行了多尺度模拟和研究,并计算出了达到完全混合所需要的特征混合时间。对不同操作条件下的多尺度混合情况进行了模拟计算和分析。结果表明:在引射流速度不变的情况下,增加喷嘴速度,可以降低达到完全混合所需要的时间;在喷嘴速度不变的情况下,增加引射流速度,可以增加达到完全混合所需要的时间;在喷嘴和引射流速度比不变的情况下,增加两者绝对速度,可以降低达到完全混合所需要的时间;在本文所研究的情况下,喷射反应器内湍流混合过程由微观混合控制。

关键词:

喷射器, 湍流混合, 多尺度, 模拟

Abstract:

The variances of macro- and micro- mixture fractions were used to represent the performance of macro- and micro-mixing.Multi-scale simulation and study of turbulent mixing in jet reactor were made and the characteristic times of macro- and micro-mixing were obtained under different operation conditions.The results showed that in the case of constant entrained flow velocity, the mixing time to reach complete mixing decreased when the nozzle velocity increased.In the case of constant nozzle velocity, the mixing time to reach complete mixing increased when the entrained flow velocity increased.In the case of constant velocity ratio of nozzle and entrained flow, the mixing time to reach complete mixing decreased when both velocities increased.In all the cases studied, the controlling step of the turbulent mixing in jet reactor was micro-mixing process.

Key words:

喷射器, 湍流混合, 多尺度, 模拟