Failing of Simulation Run

I am trying to go for CFD of a Shell and Tube Heat Exchanger, but simulation fails teling the following message. Please help. I have tried

all combinations of pressures and velocity.

Hello mmaheshwarkar,

thanks for reaching out to us in the forum, it seems like there is an issue in the setup in the Simulation.

From what I can see in the image you have two velocity inlet and two velocity outlet boundary conditions.
And it seems like you have set them up that the continuity of mass cannot be conserved.

We suggest using a pressure outlet / or pressure inlet so that the velocity can be solved by the simulation.

Can you please share your project (post a link here in the forum) so that we can have a look at it?

Best regards

Set your model to fail at 150, this way if you get challenged on different operating conditions you can say that you were optimistic in the run