SolverWarning regarding chem_eq.n and chem_eq.n_moles

[JacobCadrinAubin]

Hello, I created a model of a mixed flow turbofan based on the example mixedflow_turbofan.py. I was wondering, if I was the only one with this type of SolverWarning. I have this SolverWarning for most of the subsystems in my model.

SolverWarning:'TOC.fc.conv.fs.totals.base_thermo.chem_eq.n' exceeds lower bounds
Val: [ 3.23319235e-04 -6.93045815e-01 6.93056829e-01 -1.94550524e+00
-1.84582643e-02 2.56388425e-01 4.17449195e-02 8.59872963e-01
-1.26676179e+00 -1.56866929e-02]
Lower: [1.e-10 1.e-10 1.e-10 1.e-10 1.e-10 1.e-10 1.e-10 1.e-10 1.e-10 1.e-10]

SolverWarning:'TOC.fc.conv.fs.totals.base_thermo.chem_eq.n_moles' exceeds lower bounds
Val: [-2.08807134]
Lower: [1.e-10]

[flight-test-engineering]

Hello @JacobCadrinAubin, although I am working with another file, when changing the design and off-design points of the high_bypass_turbofan.py example, I ran into similar situation that you described.
What worked for me was to change the off-design points a bit and set them closer together - meaning that the altitude and Mach number changes from one off-design condition to the next needed to be less abrupt.
My understanding is that finding a solution to a highly non-linear problem like this has also an art component to it... :)

Hope this helps.