I'm a little bit confused about what boundary condition should I use for this fluid flow simulation. I just want to show that the outlet has a known velocity created by the fan at the outlet and an inlet/opening as open to the surrounding which is set to 0 Pa.
Kindly help me to consider which boundary condition is correct.
See different results as follows;
Fig. 1 Result 1 (Input and Ouput)
Fig. 2 Result 2 (Opening and Output)
Fig. 3 Result 3 (Opening and Output with refined mesh)
Thank you and regards,