I am performing a steady state analysis with pressure based solver and I am at a stage where I cant decide whether my solution is correct or not. This is because my residuals i.e continuity, x, y-velocity, k and epsilon have converged at 10^-5 but in my lift coef monitor the Cl is increasing at 0.0001 rate every 10th iteration. So, what should I assume now?
If anyone replies it will be of great help.
I suggest you to evaluate the domain imbalance together with residuals. Satisfactory solutions in CFD has less than 1% in domain imbalance.
Thanks for the reply Sir but is the domain imbalance equivalent to mass flux between inlet and outlet?
Please try to increase the residual upto 10^e-7 (not more than that). please try to run with this residual.. may be this will helps you.
The x and y velocity residual have reached 10^-7 and the rest are kept at 10^-5. But the point lies in the Cl curve of the domain. It is increasing continuously at a very slow rate.
if its increasing (i.e. if its diverging), then please check the boundary condition and as well as the skewness and orthogonal quality of the whole mesh.
Please do the followings:
1-The mass flow rate in should equal the mass flow rate out
2-If not , correct the stream-wise velocity component as follows,
U(i,j,k)=M (column)/m(inlet to domain).
3-Use relaxation factor (0.45-0.5)
Referring to the stream -wise velocity component:
U(i,j,k)=U(i,j,k)[M(column)/M(inlet to domain)]
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