【摘要】 多孔流体分布管广泛应用于滴喷灌、石油化工、给排水、电力、通风等领域中,不同领域多孔流体分布管的长度不尽相同,流体的流态不同,其内在的水头变化和出流情况也各不相同。结合前人理论分析结果,通过三组实验数据得出多孔流体分布管不同流态(全紊流区,完全紊流区,非完全紊流区,过渡区,层流区)下相应管长的不同,并根据不同流态(全紊流区,完全紊流区,非完全紊流区,过渡区,层流区)分区完整程度的不同得出不同类型多孔流体分布管内在水头变化趋势:对于分区完整的多孔流体分布管长管压力沿程降低,降低幅度沿程变小,到多孔流体分布管末端时压力变化趋于平缓;对于分区较完整(过渡区很小可忽略不计)的多孔流体分布管中长管压力先降低后升高,整体变化幅度不大;对于分区不完整(过渡区和层流区很短可忽略不计)的多孔短管压力沿程呈上升趋势。结合对多孔流体分布管水头变化的分析,推导出多孔流体分布管内部的水头变化和流速水头的恢复值的计算公式,为多孔流体分布管的设计提供帮助。更多还原

【Abstract】 Fluid distribution tubes are widely used in the field of drip &sprinkler irrigation,petrochemical industry,electric power, ventilation.The porous pipe length in different areas is not the same,the internal fluid flow state is different and the inner head change and outflow is also different.Combined with the previous theoretical analysis results,this paper draw the different perforated pipe flow pattern(wholly turbulence,fully turbulence,incomplete turbulence and laminar flow)with corresponding pipe length through three sets of experimental data.And according to the different partition completeness degree of flow regimes(wholly turbulence,fully turbulence,incomplete turbulence and laminar flow),the inner head change trends in different types of perforated pipes is got.For perforated pipe with long length,the pressure becomes lower along the perforated pipe and the rate of the reduction becomes smaller along the way to the end of the pipe when the pressure changes in the porous flatten;For a more complete partition(the transition zone is very small that can be negligible)perforated pipe with middle length,pressure firstly decreased and then increased,overall changed slightly;For a partitioned incomplete(transitional and laminar flow region is very short that can be negligible)perforated pipe with short length,pressure rise along the perforated pipe.Combing with the analysis of the head change of perforated pipe,the formula of the head change and the recovery value of the velocity head inside porous tube is induced,which will provide reference for the perforated pipe design.更多还原