突扩回流与大速差射流回流湍流气－固两相流动的数值模拟

Numerical Simulation of Sudden-Expansion and Large-Velocity-Difference-Jet Recirculating Gas-Particle Turbulent Flows

本文建立了气－固两相流的多连续介质模型，并分别对突扩回流与大速差射流回流这两种与实际工程应用密切相关的复杂流动条件下的受限湍流气一固两相流动进行了数值模拟。单相湍流回流流场的模拟结果与实验符合良好。两相流动的模拟结果表明，与突扩回流相比，大速差射流回流更有利于实现较高的颗粒浓度与气相回流区及低速尾流区的匹配，增加两相滑移速度，延长颗粒停留时间及强化两相间的混合。

This paper presents a multi-continum model for gasparticle turbulent flow.It was utilized to numerically simulate the confined sudden-expansion and large-velocity-difference-jet recirculating gasparticle turbulent flows which are closely related to engineering applications. The calculations for the single phase flows are in good agreement with the measured data.The predictions for the two-phase flows indicate that,compared with the sudden-expansion recirculating flow, the largevelocity-difference-jet recirculating flow is more fayorable for achieying the matching of high particle concentrations with the gas recirculation zone and its low speed wake, increasing the gas-particle slip Yelocities,prolonging the particle residence time, and intensifying the mixing between two phases.