弯曲管道内湍流流动的数值模拟

Numerical simulation of turbulent flow in a turn-around duct

关键词:  湍流  弯曲管道流动  数值仿真

Key words:  Turbulent flow  Turn-around duct flow  Numerical simulation

摘要:

为了对弯曲管道内的湍流流动特性进行有效的预测 ,用显式代数应力模式对一典型的弯曲管道内流动进行了数值模拟和分析 ,计算结果表明 :(1)显式代数应力模式能对弯曲管道内流动的平均量 (如速度、压力、摩阻等 )进行较为准确的预测 ;(2 )对模式中的ε方程做适当修正后 ,该模式能较好地模拟出流动曲率效应对湍流特性的影响 ,是对雷诺应力模式的一个比较好的近似。此外 ,该模式在形式上与标准k ε两方程模式类似 ,使用方便 ,具有较强的工程实用价值。

Abstract:

In order to accurately predict the flow in curved duct, a typical turn-around duct flow was numerically simulated and analyzed with Explicit Algebraic Stress turbulence Model (EASM). The result shows that: first, EASM can make a rather good prediction of the flow variables such as velocity, pressure coefficient, friction coefficient, and so on. Second, thanks to some modification of the ε equation, EASM can accurately simulate the influence of the curvature effect to the turbulent flow characteristic and then it’s an effective simplification of the Reynolds Stress Model. Moreover, EASM is in expression similar to the standard k-ε model, and convenient to use. So, it has a bright prospect for engineering practice.