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采用标准 k-ε湍流模型 ,对一种典型液 -液旋流分离管中的强旋湍流进行了数值模拟研究。结果表明 :该模型对切向速度的数值预报夸大了 Rankine涡中的似固核范围 ,抹煞了似固核外的位涡区 ;对轴向速度的数值预报未给出中心回流区 ;对其它流场参数的预报结果也都存在有明显的不合理之处。由此证明这种基于 Boussinesq假设的各向同性湍流模型 ,虽然在管道流、平面射流和无旋流等简单流动问题中经受住了大量计算实践的检验 ,但在强旋湍流的数值预报方面的确存在有较大缺陷。此问题的解决有赖于对该模型进行必要的修正或转而采用更加高级的各向异性模型。
A standard k-ε turbulence model was used to simulate the strong turbulent flow in a typical liquid-liquid cyclone. The results show that the numerical prediction of the tangential velocity exaggerates the range of quasi-solid-nucleation in the Rankine vortex and negates the potential vorticity region outside the solid nucleus. The central recirculation zone is not given in the numerical prediction of the axial velocity. Flow field parameters of the forecast results also have obvious irrational. It is proved that this isotropic turbulence model based on the assumption of Boussinesq has been tested with a large number of computational practices in simple flow problems such as pipe flow, planar jet and no-swirl flow. However, There is a big flaw. The solution to this problem depends on making the necessary modifications to the model or moving to a more advanced anisotropy model.