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

The axial flow threshing roller of 4LZ-3 combine harvester was divided into three sectors: feeding sector, threshing sector and separation sector. The movement of cereal passing through each sector was analyzed based on reasonable assumptions. Subsequently, formulas of absolute velocity, relative velocity and axial direction velocity were deduced considering the friction force. The results show that the helix angle of feeding sector should be smaller than the complementary angle of friction angle between cereal and helix lamina, helix angle of threshing sector and separation sector should be smaller than friction angle between cereal and leading lathing respectively.