5 Replies Latest reply on Dec 2, 2016 8:23 AM by Txon Aguirre

# cavitation in solidworks flow simulation

Dear Solidworks user

•                What are all output plot need to consider for cavitation?
•                In solid works flow simulation manual it show only density plot, in that the blue regions in the cut plot represent very low density regions. Which indicate that cavitation is                  occurring in these regions. But is there any criteria to check for cavitation?

Thanks

Senthil Ramajayam

• ###### Re: cavitation in solidworks flow simulation

flow simulation tells you if cavitation is happening and how large the region is

you can compare against other designs and see if it is larger or smaller and if the region changes

beyond that i am not aware of any further criteria

density plot is the easiest but there is also % vapor charts that can visualize the cavitation

• ###### Re: cavitation in solidworks flow simulation

the region of cavitation is that below the vapour pressure. When you turn on cavitation it is my understanding that the pressure calc is more reliable/accurate in the region below the vapour pressure. You pay a lot in compute time when you turn this on. Typically the goal is to avoid cavitation and hence you don't need to turn it on to see a good indication of where it is occurring. You turn it on when you want to examine the pressure in the cavitating region.

• ###### Re: cavitation in solidworks flow simulation

Is there any way to identify where the solid erosion is occurring due to cavitation?

• ###### Re: cavitation in solidworks flow simulation

more cavitation = more erosion

but again, flow simulation is based on the size and intensity of the cavitation, not absolutes that i think you are looking for

• ###### Re: cavitation in solidworks flow simulation

Once the pressure distribution plot is got, its easy to get it in the form of a data table. Therefore, its as simple as comparing pressure data (Px,y,z) with local vapour presure(Pv), that can be obtained, in a simple way and with a good approximation, from Atoine's equation.

The criteria is: Cavitation exists if P=<Pv.

If a non-dimensional form is prefered, then a Cavitation number can be defined from both pressures (P and Pv) and fluid velocity.

Ca=(P-Pv)/(1/2 dens V²): If Ca=<0, cavitation exists.