[ghorrocks]

1. Your expression returns a variable field of 0 bar and 309 bar in all nodal points.
2. You can define many parameters this way, but there are some restrictions. Some material properties must be constants or functions of a limited set of variables. And secondly - having material properties as a function of location is rarely physically accurate and almost always results in numerical difficulties. It is better to properly model the underlying physics.
3. I do not understand what you mean. The CEL is evaluated in context - initial conditions are evaluated at the start of the simulation, boundary conditions are evaluated each iteration, monitor point CEL is evaluated at the end of the time step/iteration.
4. Look in the installation manual for how to set up multiple processor operation. Note you will need additional licenses to use multiple processors.

[749604]

Ok, thanks. So far I have been recording the average pressure in the air domain but this includes the bore as well. I want to know the average pressure in just the upper volume of the geometry. I'm using ave(Pressure)@Locator but the locator only takes 3D volumes which for the Air domain includes the bore. So do I need to change the geometry so that the region I want is a separate 3D volume? Or is there a way to specify that I want to record the average pressure above a specific Z position, like ave(Pressure)@z>10?

[ghorrocks]

I seem to recall there is some new stuff which allows this but I have never used it so am not sure.

If I was doing this then I would define a mesh region and use that.

But an important point: You should be using the volumeAve(p)@region, not ave(p)@region. You want the volume weighed pressure, not the arithmetic average of the nodal values.

[749604]

Thanks for the heads up about the volumeAve. I was playing around trying to get the simulation to run with the single domain. I was able to use if(x>#,309[bar],0[bar]) to initialise the pressure in the domain but when I tried to use if(inside()@SubdomainName,309[bar],0[bar])it gave the following error,

Bad expression value 'Expression 1' detected in parameter 'Relative Pressure' in object '/FLOW:Flow Analysis 1/DOMAINefault Domain/INITIALISATION/INITIAL CONDITIONS/STATIC PRESSURE'.
CEL error:
Error at position 4. The condition expression in 'if' statement is not logical valued.

[ghorrocks]

inside() returns either 0 or 1. CFX is not quite smart enough to map that to boolean true or false for the conditional statement. So you can either use if(inside()@somewhere=1,309[bar],0[bar]) or even better =inside()@somewhere*309[bar]