[anon_p]

Hey Guys,

I would like to use a compressible liquid solver for my case. Thus, I need to set the reference pressure, the reference density and the bulk modulus for the liquids that I want to use. My problem is that I do not really know the influence of these values on the calculations and therefore do not know which values I should use. Can you explain me the meaning of these parameters on the simulation?

Thanks in advance.

Best regards

[xieshengbai]

Hello,

Those parameters are used to define the properties of the liquid as a response to compressibility. Basically, the reference pressure and density can be set as those at 1 bar as incompressible, and from that basis, bulk modulus represents how much the liquid can be compressed under higher pressure (from wiki: it is defined as the ratio of the infinitesimal pressure increase to the resulting relative decrease of the volume).

Do you know what type of liquid it is? For most of commonly used liquids, we have a predefined library that you can use. Go to Material > Liquid simulation > Predefined liquids, and select the liquid you want, then you don't need to define those parameters yourself. If it is not in the library, either you can refer to the parameters of a similar liquid in the library, or you can go to Liquid calculator to generate them. The latter one will be a little trickier, so let me know if you have any question.

Originally Posted by GNKK

Hey Guys,

I would like to use a compressible liquid solver for my case. Thus, I need to set the reference pressure, the reference density and the bulk modulus for the liquids that I want to use. My problem is that I do not really know the influence of these values on the calculations and therefore do not know which values I should use. Can you explain me the meaning of these parameters on the simulation?

Thanks in advance.

Best regards

[anon_p]

Hey Xieshengbai,

thank you for the reply. I will use C7H16 for my simulations and this liquid is available in the predefined library in CONVERGE. However, the given values for the bulk modulus are the same for all predefined values. Is that intended?


Best regards

[xieshengbai]

Hi,

Unfortunately, we don't have that data for each liquid in the library. So we are currently using a constant default value for all. If you don't want to use that value, maybe you can find it on Google or other sources.

Thank you.

Originally Posted by GNKK

Hey Xieshengbai,

thank you for the reply. I will use C7H16 for my simulations and this liquid is available in the predefined library in CONVERGE. However, the given values for the bulk modulus are the same for all predefined values. Is that intended?


Best regards