窄矩形通道临界流数值模拟

冷却剂通过细微裂缝泄漏的主要机理为临界流流动,准确预测临界流流量是实现破前漏（LBB）应用的关键。基于空化模型对窄矩形通道的临界流进行了数值模拟,探讨了表征气泡半径和气化核心密度的常数项（C）对于临界流的影响。结果表明,当C=1.25时模拟结果与实验值符合良好;在实验工况范围内,临界流质量流速的模拟结果与实验值的误差在±15%以内;修正后的空化模型可用于模拟计算上游温度、压力工况下的临界流质量流速以及归纳临界流流量变化规律。 

Numerical Simulation of Critical Flow in a Narrow Rectangular Channel

The main mechanism of coolant leakage through micro-cracks is critical flow, and accurate prediction of critical flow is the key to realize the application of Leak-Before-Break (LBB). Based on the cavitation model, the critical flow in a narrow rectangular channel is numerically simulated, and the influence of the constant term (C) representing the bubble radius and nucleation site density on the critical flow is discussed. The results show that when C=1.25, the simulation results are in good agreement with the experimental values; Within the range of experimental conditions, the error between the simulation results of critical flow and the experimental values is within ± 15%; The modified cavitation model can be used to simulate and calculate the critical flow under upstream temperature and pressure conditions.