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测试并分析了微压条件下小口径PE管(管径4、6mm)的水力性能,同时对现有水头损失经验公式进行修正。结果表明,压力水头小于45cm时,微管流态以层流为主;而压力水头大于45cm时,微管存在层流和紊流共存,以紊流为主。勃拉休斯公式计算的沿程水头损失与实测值存在较大的偏差。传统水头损失计算公式修正后,层流区、紊流区其理论计算值与实测值的最大偏差减小了25%和30.3%,平均偏差减小了11.1%和15.1%。修正后的水头损失计算公式能够较好地反映小口径PE管水力学性能。
The hydraulic performance of small diameter PE pipe (diameter 4,6mm) under micro-pressure conditions was tested and analyzed. At the same time, the empirical formula of head loss was corrected. The results show that when the pressure head is less than 45cm, the laminar flow of the microtubules is dominated. When the pressure head is greater than 45cm, the laminar and turbulent coexistence of the microtubules exists mainly with turbulent flow. Brachewsh formula calculated head loss along the way and the measured value there is a big deviation. After the correction formula of traditional head loss was calculated, the maximum deviation of theoretical calculation value and measured value in laminar flow and turbulent flow areas was reduced by 25% and 30.3%, and the average deviation was reduced by 11.1% and 15.1% respectively. The corrected head loss formula can well reflect the hydraulics performance of small diameter PE pipe.