1、105.5102.4104.136.936.537.3520105.3101.9103.936.435.936.6640104.899.7102.535.134.435.4760104.598.2102.233.534.588096.1101.233.232.633.61000103.492.6100.131.330.531.61120103.390.599.430.229.830.61240102.787.697.828.728.029.11h1和h2分析表2 h1、h2变截面连续性方程序号流速u1(m/s)流速u2(m/s)u1d12x10-4u2d22x10-410.160.801.41
2、1.7920.200.841.841.8930.251.032.262.3240.301.152.692.5950.351.303.112.9260.391.513.543.3970.441.643.963.7080.494.394.02分析:流体为均质、不可压缩流体,连续性方程成立数据处理实例:以第一组数据为例由据式(5)知:2h1和h3的分析表3 h1、h3流体经节流件后压头损失关系压头损失hf(cm)1.4 2.3 2.9 3.3 3.9 4.9 流速增大,压头损失增大,压头损失和速度的平方成正比 流速计算同1中的相同3h3和h4的分析表4 h3、h4流体经弯头和流量计件后压头损失和位能
3、变化关系位能差(cm)67.2 67.5 67.4 67.8 68.0 68.8 69.2 69.1 流体经3到4处,受弯头和转子流量计及位能的影响且随流量的增大,单管压力计3和4的读数差变大,流体局部阻力导致的能头损失增大。4h4和h5的分析表5 h4、h5直管段雷诺数和流体阻力系数关系阻力系数Rehf0.16 5267.110.40.12 6847.240.50.11 8427.370.70.10 10007.500.90.07 11587.640.05 13167.770.80.02 14747.900.03 16328.03Re足够大时,与Re无关,只与流体流速平方成正比 以第一组数据为例(25,水的粘度=0.8937x10-3pas)5h5和h6的分析表6 h5、h6单管压力计h5处中心点速度hu(m/s)平均u(m/s)0.400.430.371.01.10.46