管道系统中局部阻力计算

Calculation of Local Resistance Force in Pipeline System

管道系统中局部阻力的计算有几种方法 ,通常采用当量长度法和阻力系数法。由于流体在管件、阀门内的层流或湍流的性质与直管内层流或湍流的性质不同 ,当量长度法估算管件阻力降不够精确 ,而且阻力降与雷诺数及管件尺寸有关 ,单常数阻力系数法也不够精确 。

There are many calculating methods for the local resistance foree in the pipeline system,but it is used under normal conditions the equivalent length method and the resistanee coefficient method Because the laminal or turbulant properry of the fluid in the pipefttings and valves is diffevent from that in straight pipe if the equiralent length method would the resistance relicf of the pipefittings be nat aceurate evalated and the resistance relief is depended on the Reynolds coeficient and the pipefittings sizes, then the single constant resistance method is not accurate enough too.It is pointed out the 3K-equation can more accurate calculate the resistance relief in pipefittings.