This paper addresses the effect of non-flashing multiphase flow on the dynamic behaviour of direct spring operated pressure relief valves (PRV). We employ DIER’s $\omega$ method to describe the mass flux through the valve for different $x_g$ gas mass fractions, which is combined with the one-degree-of-freedom mechanical model of the PRV and the vessel pressure dynamics, providing a simulation tool for predicting venting scenarios. We emphasise on the proper description of the fluid momentum forces on the valve disc. Three typical valve geometries are considered: a ’reaction-like’ geometry with large deflection angle reversing the flow, a simple disc valve with purely radial outlet and a conical geometry, for which the direction of the flow through the valve does not change significantly. It was found that by merely varying the mass fraction of the liquid and the gas, the valve opening time changes drastically, over a range of several orders of magnitude. By using a simplified mechanical analysis and assuming frozen mixture (i.e. fixed mass fraction), a formula was developed providing an order-of-magnitude estimation of the valve opening time.

本文探讨了无闪速多相流对直接弹簧式泄压阀（PRV）动力学行为的影响。我们聘请DIER$\omega$ 描述通过阀的质量通量的方法 $X_G$气体质量分数，再结合PRV的单自由度机械模型和容器压力动态特性，为预测通风情况提供了一种仿真工具。我们强调正确描述阀盘上的流体动量。考虑了三种典型的阀几何形状：具有大偏转角的“类似反应”几何形状，可逆流；具有纯径向出口的简单碟形阀，以及锥形几何形状，通过阀的流动方向不会明显改变。已经发现，仅通过改变液体和气体的质量分数，阀打开时间在几个数量级的范围内急剧变化。通过简化的机械分析并假设冷冻混合物（即固定质量分数），