高差压调节阀中未充展两相流阻力计算

Resistance calculation of unfully developed two phase flow through high differential pressure regulating valves

迷宫式高差压调节阀为降低阀内的流体流速，采用“反向双弯头”组成“曲折流道，多级降压，迷宫密封”的阀芯结构。其流道复杂，工作介质为高温、高压下的未充展的汽水两相流，阻力计算较为困难。该文作者发展了“等（变）差压渐进设计法”，即将复杂流道分解为一系列的阻力环节，选择现有充展两相流理想均匀流阻力计算模型并适当修正，计算每个阻力环节的阻力，从而得出总压降； 随阀杆一步一步前进，根据要求的流量开度特性计算出复杂流道结构尺寸。对复杂流道中未充展的两相流阻力计算进行了有益的尝试。实验结果表明，理论计算值和实际测量值基本相符。

To reduce the flow velocity in the high differential pressure regulating valve with labyrinth, A type of complicated valve core structure were designed with tortuous flow path made from reversal double elbows. It is very difficult to calculate the pressure drop of the unfully developed two phase flow under high temperature and pressure which flow through the valve core. A calculation method called “constant (varing) pressure drop progressing step by step design method” was developed. The complicated flow path was disintegrated into a series of independent resistance units and with the valve stem end progressing step by step the dimensions of the flow path were designed in accordance with the principle that in every position the total pressure drop of the valve should amount to that required by the design goal curve. In the course of calculating the total pressure drop, the valve flow path was also divided into a series of independent resistance units. The experiment results show that design flow characteristics are approximately consistent with the flow characteristics measured in the test.