Abstract

The new two-fluid turbulence model is compared with other RANS models for various turbulent flows: mixing of two flows, flow in a flat diffuser and an axisymmetric incompressible subsonic jet. In this paper, the most popular models capable of adequately describing complex turbulent flows are considered as RANS models. Comparisons of models are carried out not only by the accuracy of the results obtained, but also by the consumption of computing resources for the implementation of these models. Therefore, the computational algorithm for all models was the same and the method of establishing, i.e., by integrating non-stationary equations, was used to achieve stationary solutions. For the numerical implementation of systems of hydrodynamic equations, a finite-difference scheme was used, where the viscous terms were approximated by the central difference implicitly, and for convective terms, an explicit scheme against the flow of the second order of accuracy was used. At each time step, the correction for the velocities was carried out through the pressure according to the S-IMPLE procedure. To assess the adequacy, the obtained numerical results are compared with the known experimental data. Comparisons of numerical results have shown that the two-fluid model is easy to implement, requires less computational resources than other RANS models and is able to predict turbulent flows with great accuracy.

中文翻译：

---

基于现代湍流模型的湍流数值模拟

摘要

新的双流体湍流模型与其他 RANS 模型针对各种湍流进行了比较：两种流动的混合、平面扩散器中的流动和轴对称不可压缩亚音速射流。在本文中，能够充分描述复杂湍流的最流行的模型被认为是 RANS 模型。模型的比较不仅取决于获得结果的准确性，还取决于执行这些模型所消耗的计算资源。因此，所有模型的计算算法都是相同的，并且使用建立方法，即通过对非平稳方程进行积分来获得平稳解。对于流体动力学方程组的数值实现，使用了有限差分方案，其中粘性项由中心差异隐式近似，对于对流项，使用了针对二阶精度流动的显式方案。在每个时间步，根据 S-IMPLE 程序通过压力对速度进行校正。为了评估充分性，将获得的数值结果与已知的实验数据进行比较。数值结果的比较表明，二流体模型易于实现，比其他RANS模型需要更少的计算资源，并且能够非常准确地预测湍流。根据 S-IMPLE 程序通过压力进行速度校正。为了评估充分性，将获得的数值结果与已知的实验数据进行比较。数值结果的比较表明，二流体模型易于实现，比其他RANS模型需要更少的计算资源，并且能够非常准确地预测湍流。根据 S-IMPLE 程序通过压力进行速度校正。为了评估充分性，将获得的数值结果与已知的实验数据进行比较。数值结果的比较表明，二流体模型易于实现，比其他RANS模型需要更少的计算资源，并且能够非常准确地预测湍流。