突缩管熵产的数值模拟

Numerical Simulation of Entropy Generation in Sudden Contraction Pipe

利用计算流体力学数值模拟软件Fluent,采用RNG k-ε模型对突缩管熵产的数值进行了模拟。模拟结果表明,引起突缩管不可逆能量损失的因素是由摩擦引起的黏性耗散和由速度脉动引起的湍流耗散。由壁面黏性阻尼产生的黏性熵产主要集中在突缩口和出口管壁面,所占总熵产的比例为52.67%;由脉动引起的湍流熵产主要集中在出口管壁面,且在缩脉处后产生显著的涡流损失,其所占总熵产的比例为47.33%。

Using the RNG k-ε model in Fluent and the CFD simulation software, simulation study for pipe entropy generation was performed in sudden contraction area. The results of numerical simulations showed： the factors which caused irreversible energy loss in sudden contraction pipe were owing to viscous dissipation caused by friction and turbulent dissipation caused by pulsate. The viscous entropy generation caused by wall viscous damping was concentrate in sudden contraction area and outlet wall, it＇s percent of total entropy generation was 52.67%. The turbulent entropy generation caused by pulsate was concentrate in outlet wall, and caused obvious eddy-current loss after vena contracta, it＇s percent of total entropy generation was 47.33%.