说明书中风管水力计算的样本

1、6.3.5 风管的水力计算 风道阻力的计算步骤如下(1) 绘制通风系统管道走向示意图，对各管段进行编号，标注长度和风管段长度一般可按两管件向中心线长度计算，忽略构件（三通、变径管、弯头等）本身的长度.(2) 选择风管内的空气流速对于钢板或塑料风管，干管内的风速为4m/s，支管内的 风速3m/s ;(3) 根据各管段的风量和选定的流速确定各管段的断面尺寸，并计算摩擦阻力和局部阻力。确定风管尺寸时应尽量采用通风管道标准规格。(4) 风管断面尺寸确定后，应按管内实际流速计算阻力。(5) 阻力计算按最不利环路（即风管最长环路）计算出系统总阻力，校核机组余压。(6) 对并联管段进行阻力平衡。以二层一区为

2、例，计算结果如下：图 6.1 二层一区风机盘管加新风系统示意图表6-3 水力计算管段编号风量L(M3/h)管长l（m）初选风速u(m/s)风道尺寸a*b(mm)流速当量直径D(mm)实际流速u(m/s)比摩阻（Pa/m)摩擦阻力（Pa)动压（Pa）局部阻力系数局部阻力（Pa)总阻力（Pa)备注最不利管路1-339023.5250x1201623.611.42.87.814.25.417.50.6511.4三通3-478054.5250x1601955.42.41217.522.86.1222.50.4810.8三通4-8141076320x2002466.122.316.122.527.36.

3、122.30.511.2三通8-12219016400x2503086.11.51.522.3176.1222.50.6915.5三通12-1628202.56400x3203566.121.43.522.5316.7727.5127.5三通16-1831205.56400x3203566.7721127.529.36.5125.40.7218.3三通18-22375046520x3203906.511.66.425.46.427148分支管路2-339013.5250x1201623.611.41.47.812.85.417.50.6511.4三通5-731523.5200x1201503.

4、651.53816.65.920.90.6513.6三通6-731513.5200x1201503.651.51.5815.15.920.90.6513.6三通4-768034.5200x1601785.93.610.817.66.1222.50.36.8三通9-1139023.5250x1201623.611.42.87.814.25.417.50.6511.4三通10-1139013.5250x1201623.611.41.47.812.85.417.50.6511.4三通8-1178054.5250x1601955.42.41217.522.86.1222.50.245.4三通13-15

5、31523.5200x1201503.651.53817.45.920.90.6513.6三通14-1531513.5200x1201503.651.51.5815.15.920.90.6513.6三通12-1568034.5200x1601785.93.610.820.914.26.1222.50.153.4三通16-17300103.5160x1201374.32.42411.113.66.7727.50.092.5三通19-2131523.5200x1201503.651.53816.65.920.90.6513.6三通20-2131513.5200x1201503.651.51.5814.65.920.90.6513.6三通18-2168034.5200x160178