已知:z12=16m,P2(表)=0.03MPa,qm=40噸/時(shí),∑Hf=4.1J/N。求:選水泵的型號(hào)
已知:[NPSH]r=3.5m,(Hf吸+u12/2g)=3J/N,Hg=3m,P0=90kPa,tH2O=20℃。求:是否汽蝕?