I've been tearing my hair out trying to learn how to use OpenModelica for the last week as I need to use it for a university project. I'm trying to model a fuel system testbed and have had some success with FuelSystem1.mo (attached), however there's some disparity between the simulated measurements and those from the physical system. This is likely down to a number of things and there of course are a lot of things I don't fully understand in OM yet, but I thought a good starting point to improving it would be to use a better pump.

FuelSystem1 uses a controlled pump with a nominal mass flow rate of 0.0316 kg/s, a measurement which was taken from the physical testbed during normal operating conditions. I think this parameter should be an output of the model rather than an input, and may be partly why the results are off. I tried to replace the pump by adding in a prescribed pump and defining the flow characteristics according to the manufacturer's data for the physical pump (see FuelSystem3, attached). The equations/variables for the system are balanced but I can't get it to successfully run a simulation - what can I do to fix this?

Any other tips that might help me develop my model and better understand Modelica would be greatly appreciated!

Might be worth adding - there's supposed to be two flow sensors, one between pipes 13 & 20 and the other between 18 & 19. These were again preventing the system from running a successful simulation, I've no idea how.

Cheers,

Calum
FuelSystem3.mo

FuelSystem1.mo