除尘管道的局部阻力系数.docx

除尘管道的局部阻力系数阻力名称简图按简图所示流速W计算的阻力系数沿直线方向自风管流出- R 1自4=1风管出阻力出口处有急剧变向磅=1.5弑=1.3蓝=0.7气流平缓转弯的出口（经过扩张或收缩）b=r=0.2dR=1.2dH=1.8dL=1.25d自7突然膨胀L>0.8d f>0f和F为任何型的截面积JL/f/F0().10.20.30.4().50.60.70.8自710.80.650.50.350.250.150.10&7=(1寸牛)2气流截面改变所产生的阻力突然收缩f和F为任何形状的截面积f/F0-0.250.3 0.50.6 0.750.8-1180.50.350.20自9 = 2.7-0.6f2/D/d11.251.51.7522.53F/f11.652.253.0546.25902.57.516318623510-15°2030°4590°1.25 1.750.10.25按与值2-2.50.15035弯管流线弯曲阻力S形管肘管02(a)圆形弯管tana = L/h(b)方形肘管14(a)圆形肘管r/d0.7511.5223自；20.50.30.20.150.12a=90°当 45°Wa<180°,取号2乂a90(b)长方形形弯管(B/h>0.2)1aS12 -S12xVh在求上式中的自;2时，取r/B代替r/d,在所有情况下,平的一侧为B,而弯曲的一侧为h。03=1502将S形管当作1.5个角度a的弯管。a90°120°135°150°1.10.550.350.2在所有情况下，平的一侧为B,而折迭的一侧为h。流线弯曲阻力带有导向叶片的直角肘管压入三通管（分叉）吸入三通管（汇合）裤脚形三通管（分叉或汇合）四通管（分叉或汇合）1618a=90°喝t=1.4lr叶片数目m= 1.4b/rF16Wg120<a< 2(r fB=fo+fn12<a<20° fB-fo+fnWna <20W|fl W| 0f 2 W2 4 2apa2< 20°f 3 W 3 t3I© Wg自590°120°135°0.250.250.150.10.10.40.20.1536Wo/Wg0.40.50.60.70.80.911.11.20000000001。2.71.71.10.70.40.250.150.10Wo/Wg0.60.811.21.41.60.40.350.20.100%-1.8-0.700.10.250.35昌7当W|=W?,取&18=416'或自18二117白、,和自2、匕3的数值按36和37的方法计算，把四通看成两个三通管。阀门及格筛阻力插板蝶阀金属网格b/D10.8750.750.6250.50.3750.250.1250200.050.070.260.812.055.5217.097.8OO(b)方形风管b/B10.90.80.70.60.50.40.30.20.10200.10.230.51.02481740200OOa051015202530350.050.240.520.91.542.513.916.22a404550556065709010.818.732.658.8118256751OO网丝直径0.270.270.660.721.561.72(mm)间距1.672.083.575.011.116.7有效面积比707667747281020.800.700.700.650.510.50计算风速采用通过网格时的风速。