Fluid Dynamic System-System Modeler: internal error

Questions
1

Hi,
I was trying a learn this software, Wolfram System Modeler, by going through one of the YT videos I came across.
System Modeler Fluid Dynamic System

I added all the necessary data but when I tried to validate the system its displaying the below-given error. It would be nice if anyone could help me resolve this issue.

Validation Error.png
Validation Error.png1920×1017 103 KB

Error : [7] 18:50 Validation of model Model1
Internal error: ExpressionUtil.typeof: ASUB({} of type Real, i): ExpressionUtil.unliftArrayTypeWithSubs: Nonempty subscript, but not array type.
Check failed for model: Model1

I’m a beginner and don’t know much about this software. Any leads would be highly appreciated.
Thank you in advance for your help.

Validation Error.png
Validation Error.png1920×1017 103 KB

2

Hi,

I think you might not have specified the nPorts for boundary and tank components.
The pump element is also missing a rotational source.

I have attached a working version of the model in the following link for your reference: https://amoeba.wolfram.com/index.php/s/Xedxxg8HdFojYqq

3

Hi, Thanks for your help. I worked for me. I changed the media to ideal gas O2, its giving me this warning,
Warning: The function.Modelica.Fluid.Interfaces.FluidPort_a$pipe1$port_a.Medium.T__h.Internal.solve can return without assigning the output variables x_zero.
Warning: Equation system in pump.V_flow and 14 other variables is too complex for checking conditional solvability that might be caused by if-expressions where the variable is only solvable in one of the branches

Could you provide some suggestions on how to remove this warning as I cannot simulate my model?

Thanks

4

I was able to simulate the model (I did have the warnings though). The model can be found here: https://amoeba.wolfram.com/index.php/s/cZRTNDYEJnk6smy

Perhaps you didn’t assign all the Mediums to O2.

5

Thanks for your help. Curious to know whether we can simulate two phase flow using cryogenic liquids? I guess liquid cryogens needs to be defined from user’s end using thermodynamic properties, right?

6

Yes, you can simulate two-phase flows but you need to create a custom Medium with the relevant thermodynamic properties.

7

And how to proceed with creating a separate media with relevant thermo. properties?
Like, I want to declare Liquid oxygen as a Media.

8

If all the thermodynamic relations are known then you can create a custom fluid using the following documentation (it will need some understanding of the Modelica language though): Modelica: Media.UsersGuide.MediumDefinition - System Modeler Documentation

9

Can we select fluid from CoolProp or RefProp? If yes, how to select them?

10

Check the following thread: Suggesting a fluid in SystemModeler
Status is still a work in progress.