CFD Online Discussion Forums

CFD Online Discussion Forums (
-   FLUENT (
-   -   Particle Relaxation Time (

chouki August 14, 2008 07:55

Particle Relaxation Time
Hello, what is the signification of particle relaxation time in multiphase flows? Can you give me reference to read more about it? Kind regards, Chouki

A. Dehbi August 26, 2008 10:29

Re: Particle Relaxation Time
Tau_p= typical time for a particle response in a flow. If starting from rest, it takes tau_p for a particle to reach (1-1/e) of the fluid velocity.

tau_p= (particle density)*(particle diameter)^2 over (18*fluid molecular viscosity)

Check: Hinds: aerosol technology


chouki August 27, 2008 09:10

Re: Particle Relaxation Time
Thank you very much but what do you mean by e (e=2.718282)? Regards, Chouki

A. Dehbi August 27, 2008 10:22

Re: Particle Relaxation Time
Yes, it is the exponential. A. Dehbi

All times are GMT -4. The time now is 03:50.