微灌压力调节器调压特性流固耦合数值计算及分析

Numerical Simulation on Regulating Characteristics of Pressure Regulator in Micro-Irrigation System by Fluid-Structure Interaction Method

针对微灌压力调节器在调压过程中内部压力、速度分布及调节组件运动状况等特性难以用传统方法分析的问题,采用流固耦合方法进行了数值计算。通过对比数值计算与实验结果发现,进出口压力的最小相对误差为0.98%,最大相对误差为14.28%,流量的相对误差为6.19%,从而验证了流固耦合方法的可行性。在此基础上,对压力调节器内部压力、速度分布以及调节组件的轴向位移趋势等特性进行了分析,结果表明:稳定工作状态下压力损失主要发生在调节组件与进口花篮堵头之间,压力损失占进口压力的28.13%～34.17%,该值随着进口压力的增加而增大;进口压力达到一定值后,调节组件的轴向位移随进口压力的增加而增大,最后稳定在13mm～13.8mm之间并呈波动性变化。所得结果可为微灌压力调节器设计提供参考。

It is difficult to analyze the characteristics of pressure regulator in micro-irrigation systems during regulating, such as the distributions of internal pressure and velocity, and the movement features of the regulating components, by the traditional methods. Numerical simulations for these processes are conducted following fluid structure interaction consideration. A comparison between the simulated and experimental results of pressure and flow rate indicates that the minimum relative error for pressure gets to 0.98% and the maximum to 14.28% the relative error for flow rate to 6. 19%. The distributions of velocity and pressure in pressure regulator, and the axial displacement of regulating component are computationally analyzed. It is found that the pressure loss occurred mainly between the regulating part and the block cap for steady working state. The ratio of pressure loss to the inlet pressure is ranged from 28.13M to 34.17% and increases with the inlet pressure. When the inlet pressure reaches a certain value, the axial displacement of the regulating part increases with the inlet pressure and finally stabilizes and varies undulatingly within 13 to 13.8 mm.