本文对圆孔射流近场的湍流统计量进行了DNS模拟研究。模拟的Re=5000,计算网格3000万,计算CPU个数为60。采用MPI并行求解了可压缩的射流守恒方程,包括连续性方程、动量方程、能量方程和理想气体的状态方程。对射流近场(30d以内,d为喷口的直径)的湍流统计量的迁移规律进行了系统的分析。研究了入口湍流条件对射流统计量的影响。本文提供的DNS数据能够克服实验测量的困难,从而为修正k~ε模型的系数提供了可靠的依据。
The fluid dynamics of circular jet in the near field region is investigated in this paper by the DNS method. The compressible Navier Stokes equations are solved including the continuity, momentum, energy and perfect gas state equations in order to give a clear understanding of the jet development in the near-field region. The Reynolds number is about 5000, and the total grids used in our simulation is about 30 million. The evolution of turbulent properties in the near-field region is presented and analysed explicitly in our paper. In addition, we investigate the effect of inflow turbulent boundary conditions on the turbulent properties in the near field region. The DNS database obtained from our simulation is quite useful for modifying the existed RANS models, such as k-ε or other models in future research.