基于流体体积函数模型的横板型稳压罐内气液两相流场仿真研究

针对水流量标准装置中横板型稳压罐,基于Navier-Stokes方程建立罐体计算流体动力学仿真模型。使用湍流模型、流体体积函数瞬态模型和有限体积法进行离散,并在近壁区采用标准的壁面函数法进行修正,完成横板型稳压罐内部两相流场的数值模拟。数值结果显示空罐充水流态依次经过无水状态-射流-上壅-漫流-稳定状态,同时形成掺气现象和泡状流;气液体积比1:3情况下,满罐充水流场有固定周期的晃荡现象,上侧形成逆时针转动的漩涡气腔,流场湍流粘度较小,分布较均匀,稳定效果最好。

Simulation Study on Gas-liquid Two-phase Flow in the Horizontal-baffle Type Surge Tank Based on the Volume of Fluid Model

For the horizontal-baffle type surge tank of the water flow standard facility, a computational fluid dynamic model was established on the basis of the Navier-Stokes equations. The numerical simulation of the two-phase flow field characteristics in the surge tank was achieved through the turbulence model and volume of fluid transient model, by applying the finite volume method for performing discretization, and standard wall function for modification in the near-wall region. The calculated results showed that, the water flow in the empty tank passes through the following states: anhydrous state, jet flow, upper backwater, overflow and steady state. Meanwhile, aerated flow and bubble flow were formed. In the case of gas-liquid ratio 13, there was a phenomenon of water sloshing in the flow filed of the tank with fixed period, and a vortex gas chamber was formed in the upper side which rotates counter clockwise. The flow field was characterized by lower turbulent viscosity, relatively uniform distribution and best stable performance.