基于颗粒湍流和颗粒碰撞相互作用规律的湍流模型的研究

颗粒湍流和颗粒碰撞的相互作用规律是两相流动中的核心问题。用颗粒湍流模型和颗粒碰撞的动力论模型叠加的方法在研究两相湍流流动方面取得了一定的成效,但是还有待改进。本文基于颗粒湍流形成大尺度脉动和颗粒间碰撞引起小尺度脉动的概念,从双流体模型出发,建立了两相流动的双尺度kp-pε两相湍流模型。利用该模型对下行床和突扩室内的气固...

Study of turbulence model on the interaction of particle turbulence and particle collision

The key problem in turbulent gas-particle flows is to understand the interaction of particle turbulence and particle collision. Based on the approaches by combination of the particle kinetic theory with particle turbulence models, previous studies make some progress. However, theoretically they remain to be justified and improved. In this paper, based on the concept of particle large scale fluctuation due to turbulence and small scale fluctuation due to inter-particle collision, a particle two-scale k-epsilon turbulence model is proposed in the framework of two-fluid models. This model is used to simulate gas-particle flows in a downer and in a sudden-expansion chamber. The simulation results are compared with experimental results and the simulation results obtained by the five-equation turbulence model which combines single-scale k-epsilon two-phase model with the particle kinetic theory. It is found that the present model makes some improvement.