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

In order to improve the efficiency of watersaving irrigation in agriculture, the round rotatory jet sprinkler was proposed. The CFD numerical simulation method of the sprinkler was determined. Depthtowidth ratio (k/w), potential difference ratio, split distance ratio and side wall angel were selected as the experimental factors, and frequency of wallattached switching and flow amplitude were taken as the indexes. The optimum structure of internal channel of sprinkler was obtained by orthogonal test. By means of highspeed photography technology, the frequency of wallattached switching of jet was measured, and the inlet flow rate of sprinkler was monitored. The results showed that the simulated flowpressure relation was basically consistent with the experimental results. The relative error range was from 2.1% to 4.0%, and the variation trend of the frequency of wallattached switching of jet with the inlet pressure was basically the same, and the relative error range was from 7.7% to 22.2%. When the inlet pressure was 0.15MPa, 0.20MPa and 0.25MPa, the hydraulic properties of PY210A impact sprinkler and jet sprinkler were studied, respectively. The flow rate of jet sprinkler was small (1.19~1.53m3/h), and the range was long (13.0~15.7m), the sprinkler irrigation intensity was small (2.85~3.63mm/h), and the rotation period was short (81~105s). The precipitation of impact sprinkler was “saddle”, the precipitation near and far away was relatively large, the precipitation of jet sprinkler was “triangle”, and the precipitation was decreased with the increase of range. The research provided a reference for the structure design and hydraulic performance optimization of the round rotatory jet sprinkler.