多孔出流管水流阻力及压强水头分布规律研究  

Research on Flow Resistance and Pressure Head Distribution of Multiple Outlets Pipeline

作　　者：郑超[1,2] 吴普特[2] 朱德兰[2] 张林[2] 王剑[2] 张桂春[2] 

机构地区：[1]西北农林科技大学资源环境学院,陕西杨凌712100 [2]西北农林科技大学中国旱区节水农业研究院,陕西杨凌712100

出　　处：《节水灌溉》2014年第3期24-29,共6页Water Saving Irrigation

基　　金："十二五"国家科技支撑计划(2011BAD29B00);农业科技创新专项(Z109021207);国家"111"计划项目(111-2-6)

摘　　要：对DN32×20T型三通管(多孔出流支管局部水头损失主要发生位置)进行了局部水头损失试验研究,结果表明光滑紊流区内主管至侧管流向局部水头损失系数1随雷诺数的增大而变化很小,随分流比的增大而增大;而主管至直管流向局部水头损失系数2随雷诺数的增大而减小,随分流比的增大先减小而后增大;并给出了局部水头损失系数1与2的经验公式。与实测值对比得出:提出的沿支管方向毛管进口压强水头经验计算公式具有较高的计算精度;最后,利用本文提出的局部水头损失系数经验公式分析了等距、等流量多孔出流支管局部水头损失与沿程水头损失的比值hj/hf的变化规律,并给出了扩大系数K的经验公式。Experiments were conducted to test the flow resistance of PVC tee pipe DN32× 20. The results showed that the effects of Reynolds number on the local resistance coefficient of main branch to side branch 41 was not significant, and increased with growing of flow rate. Local resistance coefficient of main branch to straight branch ζ 2 decreased with the increase of Reynolds number. It firstly decreased and then increased when flow ratio was growing. the local resistance coefficient. As compared with the experiment Also, empirical equations were given simultaneously to calculate results of the pressure head distribution of multiple outlets pipe- line, the empirical equation proposed had high calculation accuracy for lateral inlet pressure head along the manifold. Finally, the proportion of local head loss to frictional head loss for multiple outlets pipeline was analyzed by using the empirical equation of the lo- cal resistance coefficient in this paper. Then a formula of the coefficient to account for local head loss was given.

关 键 词：多孔出流管 T型三通管 局部水头损失系数 扩大系数 

分 类 号：TV134.2[水利工程—水力学及河流动力学]