please tell me the differance ammong the following boundry conditions used in CFD codes wall boundry outlet boundry symmetry thanks Muhammad zubair

My guess is: Wall boundary = solid wall. (no slip, constant temperature, flux,etc)

outlet boundary = extrapolated boundary (reflective). when u can neglect boundary layer effects, i think u would more likely use this boundary condition

symmetry = as the name implies symmetry. to reduce computational time and resource

have a look http://www.grc.nasa.gov/www/winddocs/user/bc.html it is related to wind code but i think it is useful.