Equilibrium Reactor Unit Problem

[nrgeng]

Solve failed after reactant concentration was doubled

In a study of reaction conversion for varying initial concentrations, the following occurred:
The flow rate of CO2 was doubled after the flowsheet solved, then the flowsheet failed with the error message:
"error: calculate failed for unit Equilibrium Reactor: Solution failed: Newton step failed: Matrix singularity"

Is this an expected behavior or is there reaction chemistry behind this?

[jasper]

Can you send me the fsd file so that I can check what's happening?

[nrgeng]

I e-mailed a flowsheet that exhibits a problem similar to the described problem, but with much simpler Settings. Hope you can find a solution.

[jasper]

I did not receive it. Can you send it again?

[jasper]

The problem was numeric in nature. I think the update that is currently available from CUP will fix it. Can you try?

[nrgeng]

The CUP update solved the flowsheet problem as submitted, solved the original more complicated flowsheet, and has made progress on another long-standing problem reported earlier (more later on this). A good bit of problem solving has been completed with your update--Thanks! ...

[jasper]

Glad to hear it. Thank you for reporting the issue.