ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

Aiming at the problem that the current sprinkler flow control is not fine enough, the precise variable adjustment of the irrigation flow of the Senninger i-Wob2 sprinkler was realized by installing a V-type flow control valve in front of the sprinkler as an actuator. Through the hydraulic performance test of the valve body, the mathematical relationship between the pressure before the valve, the opening of the valve body and the flow of the nozzle was established. According to the mathematical relationship, the overall structure of the variable irrigation control was designed, and the specific operation steps of the control structure were clarified, so as to realize the precise adjustment of the irrigation flow. The results showed that the flow calculation formula and the calculation method of the corresponding parameters were established, and the characteristic flow coefficient KL of the mathematical model of pressure-opening-flow was 20.40, the pressure prediction coefficient KP after the valve was 0.97, and the flow prediction coefficient Kφ was 7.08 through the hydraulic performance test data of the valve body. The range and flow rate of the nozzle changed obviously with the valve opening before the opening of 60%. However, after the opening was 60%, the range and flow rate changed with the valve opening was getting smaller and smaller;the steady-state relative deviation of the flow regulation of the control valve did not exceed 6.67%, the adjustment time did not exceed 42 s, and the measurement accuracy was above 96%. The research result realized the accurate regulation and control of sprinkler irrigation flow through the flow control valve, and provided strong data support for the application of flow control valve in variable irrigation.