基于OpenFOAM平台的钝体稳焰器尾流动力学分析

OpenFOAM framework based fluid dynamics analysis of bluff-body flameholder wake

在具有高速来流的燃烧室结构中被广泛采用的钝体稳焰器主要通过尾流流场中的剪切层以及低速回流区达到稳定火焰的目的,因此有必要对尾流非稳态流场进行流体动力学分析。本文基于OpenFOAM开源计算流体力学平台对Volvo试验钝体稳焰器非稳态流场进行仿真计算,并采用Omega涡识别方法以及动力学模态分解方法对计算结果进行分析以获取流场流体动力学特性。通过与试验结果进行对比,表明采取κ-ωSST IDDES湍流模型能够获得较为详细的钝体稳焰器尾流流场结构;Omega涡识别方法能够有效识别尾流流场涡结构;采用动力学模态分解方法能够获得具有明确物理意义的流体动力学模态,对于钝体稳焰器尾流动力学研究具有重要意义。

The bluff-body flameholder is widely used in high-speed inflow chambers.As it creates a low-speed wake area and shear layers to prevent flame blowoff,the fluid dynamic investigation of its unsteady wake flow is needed.In this paper,the transient flow field of Volvo bluff-body structure was simulated and calculated.Based on the Open source Field Operation and Manipulation(OpenFOAM)framework.The dynamic characteristics of wake flow were investigated based on the analyze the calculation results of Omega vortex identification method and dynamic mode decomposition(DMD)method.Compared with experiment results,the results show that theκ-ωSST IDDES turbulence model can be used to obtain a more detailed turbulent wake flow field structure of the bluff body flame stabilizer.Wake flow vortex structures can be identified with Omega vortex identification method effectively.It also indicate that the dynamic modes obtained from DMD method is physical significant for understanding of the wake flow hydrodynamic characteristics.