Study On The Optimal Operation Of Valve In Course Of Distribution About Urban Network

The optimal operation in course of distribution about urban network takes a pivotal position among so many means of modern urban water supply pipe network system management.It is the focus of this paper about that how to determine the higher sensitivitive tube segment about node pressure and the valve with higher sensitivity about node pressure on it.For specific water, its flow state is the main factors that affect the pipe segment node pressure.In the pipe section contains the valve, the changes of valve opening degree will affect the flow state,so the studying about the characteristics of the flow state in pipe sections under valve scheduling conditions is the theoretical premise of bringing about optimal scheduling to pipe network.Based on a microscopic model of the pipe network hydraulic morphology, adjust the pressure of regulator pipe segment node by adjusting the degree of opening of the valve,at the same time,combine the results of previous studies,establishe model by using K-ε equation,discuss the change of the head loss caused by the changes in the valve opening degree,try to find a method to determine the change of node pressure accurately.Based on determining of the pressure pipe network node accurately,in order to solve the problem of imbalance in the pressure of the water supply network system,in this paper, i used node pressure sensitivity method and fuzzy clustering method to discuss pipe network in partitions;determine optimal adjustment tube segment by pipe friction coefficient of the node pressure sensitivity equation; determine the best regulator valve and its best opening degree by valve opening degree of the node pressure sensitivity equation.The main conclusions of this paper:1.Flow state has changed when it flowed through the valve, that is the main reason for formation of vortex area appeared, which caused the pipe friction coefficient of pipe sections near the valve were different. At the same time,the length of the pipe sections interfere with valve opening degree are not the same, So the pipe network pressure monitoring points should be set beyond the largest disturbance length of the pipe sections to ensure the accuracy of the measured data.2.It is facilitate to set better pressure monitoring by using node pressure sensitivity equation, so that it can accurately reflect the node pressures and pipe network running status changes in the parameters of the various regions.3.Take valve scheduling way, not only can effectively reduce the partial pressure of the pipe network, ensure the safety and reliability of the water supply, but also can reduce the amount of pipeline leakage, pipe network run more economically.