Much work in thermal/fluid problems involve steady state cases. I have been playing around with NonlinearSolve.jl and it works well. What I’m having trouble is in the integration it with ModelingToolkitStandardLibrary.jl.

I have not been able to use `NonlinearSystem`

instead of `ODESystem`

and I don’t know if this is even possible since the components in ModelingToolkitStandardLibrary.jl extend `ODESystem`

.

If every component has has zero time derivatives, `ODESystem`

and `structural_simplify`

return a nonlinear system of equations as expected (it is a DAE solver after all…) that can be integrated using something like

```
sys = structural_simplify(model)
prob = ODAEProblem(sys, Pair[], (0, 10.0))
sol = solve(prob, Tsit5())
```

and the solution will have two time steps: the first and the last (as expected). Is it possible to use `NonlinearSystem`

directly or is this ‘hack’ is the only/best approach?

Thanks

Paulo