Simulation study on key parameters of valve control in main pipe of self-pressure irrigation pipe network
In order to eliminate the influence of valve closing water hammer on large-scale water pipeline in irrigation area and ensure the safe operation of water pipeline,in view of the characteristics of the valve closing water hammer in the water pipeline of the irrigation area,this study took the water pipeline of an agricultural irrigation area in Karamay,Xinjiang as an example,based on the basic theory of water hammer calculation,the protective effect of different intake and exhaust valve parameters is simulated by numerical calculation,and the valve closing time law of large diameter and large flow pipeline is simulated numerically.The installation of 14 intake and exhaust valves can ensure the normal valve closing of the pipeline without negative pressure.Five intake and exhaust valves are installed at the pile number(k0+066)at the bend of the head end to form an intake and exhaust valve group.Three intake and exhaust valves are installed at the pile number(k0+562)to form an intake and exhaust valve group,and an intake and exhaust valve is installed at a distance of about 1 100 m from the pipeline.When the pipeline flow rate is 0.5-6.0 m3·s-1,a one-stage linear valve closing is adopted,which can be closed within 6.0 h.The two-stage valve closing is adopted at 6.0-10.0 m3·s-1,the valve is closed quickly in the first third of the time.With the increase of flow rate,the fast closing angle is reduced from 70%to 50%,and the valve closing time is increased from 6.0 h to 9.0 h,which can eliminate the negative pressure of the pipeline.Through the study of water hammer and valve closing time of pipeline valve closing,the valve closing time of pipeline is reduced.
irrigation pipe networkgravity flowintake and exhaust valvesvalve closing law
万方数据
维普
