001=4.19m/s;矩形天沟排水量Q=4.19×0.0203×1000=85.06L/s。半圆形部分:半径为75mm;计算过程:湿周=3.14×0.075=0.2355m;过流面积=0.5×3.14×0.075×0.075=0.0088平米;水力半径=0.0088/0.2355=0.0374m;流速v=((0.0374)×(0.001))/0.001=3.54m/s;半圆形天沟排水量Q=3.54×0.0088×1000=31.15L/s。FX100排水沟排水能力=85.06+31.15=116.21L/sFX150排水沟基本资料:排水沟型号:Channeltype16mm缝隙式成品排水沟FX100排水沟断面尺寸(宽x高):Channelsection(WxH)150X210mm盖板尺寸Gratingsize排水缝净宽c/w:16mm泄水面积inletsection:160cm2/m雨水量:Rainwaterrunoff根据排水面积和当地暴雨强度定排水沟段长度:Trenchlength50m单位长度泄水量:Channelinletpermeter2.32L/s/m出水口数量:Numberofsumppits1(出水口位于沟段末端)水力计算长度:Hydrauliclength50m四、FX200排水沟水力计算42/30.51、已知:水深=0.26米;沟宽=0.20米;粗糙系数n=0.001;2、计算:计算时将U形排水沟分为上部矩形和下部半圆形计算。矩形部分:水深160mm,底宽:200mm;计算过程:湿周=2×0.16+0.2=0.52m;过流面积=0.2×0.16=0.032平米;水力半径=0.032/0.52=0.0615m;流速v=((0.0615)×(0.001))/0.001=4.93m/s;矩形天沟排水量Q=4.93×0.032×1000=157.76L/s。5