双尺度二阶矩颗粒湍流模型和提升管内稠密两相流动的模拟

稠密气固两相流动是当前国际上的研究热点,常常采用将颗粒湍流模型和反映颗粒碰撞作用的动力学模型叠加的办法来构造稠密两相流动的湍流模型。但是，对颗粒湍流模型，国内外尚没有进行双尺度湍流模型的研究。该文基于将颗粒脉动分成湍流引起的大尺度脉动和颗粒间碰撞产生的小尺度脉动的概念，建立了一种新的双尺度二阶矩颗粒湍流模型，并对提升管内的稠密气固两相流动进行了模拟。所得颗粒浓度及速度分布和实验数据吻合较好，能揭示出提升管内的环-核流动结构。该模型的结果比单尺度二阶矩两相湍流模型的结果有所改进。

Simulation of Dense Gas-particle Flows in a Riser Using a Two-scale Second-order Moment Particle Turbulence Model

The dense gas-particle flow attracts more and more attention in recent years, the two-phase turbulence model which is composed of a particle turbulence model superposed with the kinetic theory of inter-particle collision is widely employed, but the concept of multiple-time-scale has not yet been used for simulating particle turbulence. A new two-scale second-order moment particle turbulence model is developed, based on the concept of particle large-scale fluctuation due to turbulence and particle small-scale fluctuation due to collision. It is used to simulate dense gas-particle flows in a riser. The predicted results are in reasonable agreement with the experimental results and show the core-annulus flow structure. It is found that the two-scale model is somewhat better than the single-scale second-order moment turbulence model.