典型管网试验系统的随机负载仿真

Simulation of Random Load of Typical Pipe Network Test System

为了检验某类型船舶集中供水管网系统设计的合理性和验证数字仿真结果的准确性,设计了一套典型管网试验系统.典型管网试验系统以某型船舶集中供水系统的典型供水单元为蓝本,采用了差压式减压阀来模拟实际管网的纯水头差,采用节流阀来调节流动阻力损失,从而达到权衡考虑试验经济性与试验结果有效性的目标.设计了一套可编程控制器(PLC)控制系统,用于调节各支管的阻力特性与负载流量,检测与记录管网上各重要部位的压力与流量.通过PLC编程,利用线性同余发生器产生的随机数,实现管网对负载的随机控制,并对随机负载下的每层支管的压力与流量进行统计分析.试验结果表明,在随机负载的作用下各层支管末端的流量都充足,末端出现供水不足的估计概率很低,从而验证某类型船舶集中供水管网系统设计是合理的,在设计中进行的数字仿真结果是比较准确的.

To verify the rationality of the design of the centralized water supply system on a certain type of shipand the accuracy of the numerical simulation results,we designed a typical pipe network test system,taking thetypical water supply unit of a centralized water supply system on a certain type of ship as a model,using the dif-ferential pressure relief valve to simulate the actual water head,and using the throttle to adjust the flow resis-tance loss,so as to achieve the balance of economy and validity of the test. We designed a set of programmablelogic controller（PLC）system for regulating the resistance characteristic and load of each branch,detecting andrecording pressure and flow on the important positions of the pipe network. We realized the random controlling ofload by PLC,using the random number generated by linear congruence generator,and statistically analyzingthe pressure and flow of each branch under random load. The results show that the flow at the end of each branchis sufficient under random load,and the probability of water shortage at the end of each branch is very low,thusverifying that the design of water supply system on the ship is reasonable and the simulation results are accuratein the design.