Nodal boundary condition

Hello Prabin,

I would suggest searching SimLab Help (F1 key) for more information regarding this tool. This is a screenshot directly taken from there.

I suspect this option is available in cases like having already some results and you wish to map them into your existing solution. Of course, other applications as well.

I hope this helps.

Kindly,

Ioannis Makris

The concept of the 'FixedPressureNode' typically applies to cases where there are no other pressure boundary conditions - and is used to set a base pressure.  For a case with an inlet and outlet - the outlet is typically set as outflow BC with a specified pressure.  That sets all other pressures in the solution relative to that pressure at the outflow boundary.  In internal flows (no inlet/outlet) there is no pressure boundary condition, so the resultant pressures can 'vary' with no relation to previous time steps / iterations.  One would still get the same pressure difference, but the values could vary.  That single node with a fixed pressure helps ground the pressure to a given level.  One would normally want to set that in a location where there is not much action in the flow.  This is not so important in a steady-state case, but can be quite important in a transient as all the time steps should be related.