Hi:

It's easy to get shear stress in the wall in fluent.But I need the distribution of shear stress all over the domain.A friend suggested that shear stress all over the domain was available through buiding walls in the whole domain.I tried it .But I failed because fluent only caculates the shear stress in the walls.Who knows how to get shear stree at any point?

Hi , You would need to write a UDF. Use DEFINE_ON_DEMAND macro where in you access each cell in your domain. FLUENT gives the derivatives at each cell C_DUDX(c,t)for example gives you du/dx where c is the cell_t type variable and t is the cell thread. Form the shear stress components Tauxy= C_MU_L(c,t)*(C_DUDY(c,t) + C_DVDX(c,t)) form the rest similarly Tauxz, Tauyz etc. Hope this helps. Let me know if you need me to be more specific. Regards Ajay

Ajay Rao:

Thank you for your advice.I never write a UDF before.Now i am learning c language and writing a UDF. I want you to be more specific.Thanks very much!