讨论题:4-8 已知:ps=2300kg/m3p=0.674kg/m3 Vs=1000m3/hp=36×105Pas,标准式 D=0.4m→h=0.2m.B=0.1m 1000/3600 13.89m/s 0.1×0.2 puB 9×3.6×103×0.1 8.03511 11s 14×5×13.89×2300 D da=0.27 573mA=8 4×0674×13.892=520Pa讨论题：4－8 已知: ρS=2300kg/m3 ρ=0.674kg/m3 VS=1000m3 /h μ=3.6×10-5Pa·s，标准式 D m h m B m =  = = 0.4 0.2 , 0.1 1000 / 3600 13.89 / 0.1 0.2 u m s i = =  5 9 9 3.6 10 0.1 8.035 3.14 5 13.89 2300 C i S B d m N u     −    = = =      50 0.27 5.73 S i D d m u    = = 2 2 8 4 0.674 13.89 520 2 i f u p Pa   = =   =