Viscous flow simulation
 

Hello,

I am currently implementing a Navier-Stokes solution on 2D unstructured meshes in which the cells near wall boundaries and wakes are stretched. May I know if anyone knows about the implementation of 2nd/4th order smoothing on stretched triangular cells. Would appreciate suitable references on this matter.

Thanks very much, Chan K I

Re: Viscous flow simulation
 

hi Chan,

well, can u be more specific! I mean are you using pressure based methods (SIMPLE ect) then i can help. I have implemented a pressure based method on unstructured grids (2-D traingles). Regarding the stretched cells i am afraid that to say that the accuracy of viscous terms is considerably affected by aspect ratio of the traingles.Consider hybrid grids (quads in B.L.)

Abhijit Tilak

Re: Viscous flow simulation
 

Hi Abhijit,

I'm using a density based method for compressible flow simulation over a NACA 0012 airfoil.

Regards, Chan K I

Re: Viscous flow simulation
 

hi chan,

it's not clear to me what smoothing are u refering to. bcos need for smoothing arises in case of Pressure based methods. I can give u some references 1. 'An Efficient & Stable Solution Procedure of Comp. Turbulent flow on General Unst. Meshes" by L.Davidson AIAA 95-0342. (u can download this at Prof Lars Davidsons site Univ of Chalmers, Dept of Thermo-Fluids, Sweden) search thru google. U may find many more papers here.

2. "A fully inplicit NS Algorithm for Unst Grids incorporating two eq turbulence model". by D.D Knight AIAA 96-0414. (U can download this at Prof Knight's website, Dept of Mech & Aero Rutgers NJ.

I hope these help. Abhijit Tilak

Re: Viscous flow simulation
 

Hi Abhijit,

Thanks very much for the sources of references.

The smoothing is the addition of artificial viscosity of the type described in Antony Jameson's "Improvements to the Aircraft Euler Method."

Hope that rings a bell.

Best regards, Chan K I

Re: Viscous flow simulation
 

hi chan,

well , i don't know anything of the method you are saying. so i can't be of much help. thanks & good luck abhijit

Re: Viscous flow simulation
 

(1). I think, Prof. Jameson has a webpage at Stanford University, Department of Aeronautics. (2). Why not send e-mail directly to him? So, you can get his answer directly.