need help**
 

I have question.
In my case initial pressure and velocity of the fluid is 140 mmHg and 0.4m/s . I don't know velocity and pressure at the outlet.

I set velocity at the inlet 0.4 m/s and mass flow rate at the outlet (mass flow rate= inlet velocity * density of the fluid)

I introduce initialization condition velocity 0.4m/s and pressure 140mmHg .

When I run the solution and check the monitor points , I could not find the inlet pressure is not 140 mmHg .Kindly help me how to proceed.

Thank you

compressible flow? If so then your boundary conditions are underconstrained.
If incompressible then it doesn't matter since it is only a relative pressure.

I'm not sure if this will work, but you could try to Define Outlet Pressure as:
(140mmHg - (areaAve(Pressure)@inlet - areaAve(Pressure)@outlet))
and define inlet with your 0.4 m/s
One thing that might help is making a good initial condition pressure guess that includes the pressure drop through the geometry.

You could also iterate your outlet pressure using a monitor point and change it while its running to achieve your desired inlet pressure.