李志鹏,高正明

• 1:北京化工大学化学工程学院
• 2:北京化工大学化学工程学院 北京100029
• 3:北京100029

摘要(Abstract)：

利用大涡模拟方法研究了涡轮桨搅拌槽内的流动特性,采用了三种亚格子模式:标准Smagorinsky-Lilly模式(SLM)、Smagorinsky-Lilly动力模式(DSLM)和亚格子动能动力模式(DKEM),并将模拟结果与标准k-ε模型及文献实验数据进行了详细的比较。结果表明:大涡模拟方法可获得搅拌槽内的瞬态流场;对桨叶区时均速度及湍流动能的预测与实验数据相吻合,比标准k-ε模型计算结果有明显改进,三种亚格子模型中DSLM和DKEM模拟结果更好。同时分析了大涡模拟中桨叶端部附近湍流动能估计偏差的原因,发现主要是由于对轴向湍流均方根速度的预测偏差造成的。大涡模拟方法为搅拌槽内非稳态、周期性的湍流流动和湍流特性的研究提供了强有力的工具。

关键词(KeyWords)： 计算流体力学(CFD);大涡模拟(LES);流动特性;搅拌槽;涡轮桨

Abstract:

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基金项目(Foundation):

作者(Author): 李志鹏,高正明

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