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