[gokhanS]

hi guys i have a problem with my basic analysis

my case is a simple recalculation of 2d puiseulle flow with numerical. i have surface domain 1m x 40m and i made laminar flow inside with changing velocity inlet. i added constant heat flux at top and bottom wall with same value, for example 10w/m2.

i expected that average outlet temperature have same value with calculated from theoritical equation. but it was not same.

M^dot(mass flow inlet) x Cp x (Toutlet - Tinlet) =Qdot(heat flux) x A (area)

in this equation with known mass flow inlet, Cp, heat flux and Tinlet, Toutlet can be calculated. But, calculating outlet temperature in cfd-post with drawing line at outlet and using calculator for average temp. at this line is not give same value with theory above.

so, what i still have missed, it is a very basic convection relation and it has to be give same results with any simple numerical case