[rypersaud]

Hey guys, need some help with convergence. The application involves a 3" inlet pipe with 52 m/s velocity discharged into a 26"X50" duct. The duct has a U-bend with a 20" outlet.

This is a very slow flow problem due to the large size of the duct. We are expecting the velocity at the outlet to be approximately 1 m/s.

Used a surface monitor plot at the outlet to look at the velocity, and scaled residuals criteria of 1e-5. The velocity of the outlet appears to have approached a value, however the residuals are quite high. I ran 5000 iterations to exclude the effect of under relaxation factors. I have posted the plots below.

Any suggestions, or direction on how to improve the model will be great. Thanks!

residuals 5000.jpg

velocity 5000.jpg