why the cavitation incepts in the area of high pressure ?
 

I use the software FLUENT 14.5 to simulate this case.
I use liquid-vapor two phases method：I choose the k-e model, two phases mixture model and s-e-a model.
Boundary conditions are as follows:pressure inlet,total pressure is 101325 Pa; volume fraction of vapor is 0 at the inlet.; Pressure outlet, 0 Pa.
The result shows that the pressure in upstream area is higher than 8.8e +04. I think there shouldn't be cavitation. But the result shows that the vapor volume fraction is higher than 6.5e-03. I don't think it is reasonable.
I tried other models like schnerr-sauer model and zwart-gerber-belamri model.The results are same as this.
I think maybe you can help me. Thank you.

http://a4.images22.51img1.com/6000/3...1b41e4eb39.jpg

http://ad.images22.51img1.com/6000/3...598580dedd.jpg

Hi
What is your operating pressure? and what cavitation pressure you have set on the mass tab in define>phases>interaction?
Be careful that cavitation pressure is an absolute value.
check your initialization pressure.Maybe your run is initialized with a lower pressure than cavitation pressure.
Its better to converge your solution under non-cavitation condition, then activate cavitation.

Best regards

Thank you for your reply. I am very appreciate that.I have resolved this problem. The result I display is a wrong calculation result.
The cavitation pressure I set is 3540 Pa, and I used the singhal-et-al model.I think it is alright.
The problem is I gave a bad initialization value of Turbulent Kinetic Energy, Turbulent Dissipation Rate,and phase-2 volume fraction. After I revised them, I got the reasonable result. By the way, I am a rookie of CFD. Thank you again for your help.
Best wishes.