- **Main CFD Forum**
(*http://www.cfd-online.com/Forums/main/*)

- - **Question about Low Re turbulence modelling.
**
(*http://www.cfd-online.com/Forums/main/864-question-about-low-re-turbulence-modelling.html*)

Question about Low Re turbulence modelling.
Hi! Friends. I had implemented the Chien's low Re Number Turbulence Modelling . But I had a problme to calculate the dimensionless distance, y+. y+ is generally expressed in the following form. y+ = u* y/nu In above expression, friction velocity, u* ,is equal to sqrt(tau_w / rho ). What is the concrete definition of tau_w ? Would you like to inform me the implementation method of tau_w? For example, as laminar flow, does tau_w have only the form, mu (partial U /partial y)? Is it right?
Thank you. |

Re: Question about Low Re turbulence modelling.
y+ is the same for the Low K-e model as it is for the standard K-e model:
y+ = (((density^2 * Cmu^(1/2) * K)^(1/2))/viscosity) * (distance from wall) where Cmu is the constant 0.09 and K is the kinetic energy. Remember that you need a very fine mesh at the wall for the low K-e model, usually with y+ < 1. David Creech CFD Literature CFX User Subroutine Archive |

All times are GMT -4. The time now is 01:26. |