How surface tension affect delta t?
 

Hi,

For two fluid flow with strong surface tension (VOF method, no phase change), how does it affect determing delta t?

Is there any dimensionless number (such as Courant number) that can be used to roughly calculate the maximum delta t for stability (transient problem)?

Regards,

Pei

Re: How surface tension affect delta t?
 

There is a nondimensional number related to surface tension effect, We, Weber number.

Re: How surface tension affect delta t?
 

HI, Junseok,

Thanks for the reply. I understand that Weber number is the ratio between inertia force and surface tension force. But, for CFD, how to use this number to calculate maximum delta t allowed?

Using Courant number as an example:

delta t = CFL * delta x / maximum velocity

Pei

Re: How surface tension affect delta t?
 

Take a look at Mark Sussman1 and Elbridge Gerry Puckett's paper. You will find what you wanted.

Journal of Computational Physics 162, 301–337 (2000)

A Coupled Level Set and Volume-of-Fluid Method for Computing 3D and Axisymmetric Incompressible Two-Phase Flows