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Error: Optimization objective seems to be unbounded. Revise objective, bounds, and scaling.

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Hello,

I've modeled a BES coupling transport of diluted species, secondary current distribution and laminar flow. My objective function is an energy efficiency one, so basically eff=work(out)/work(in) which I am attempting to maximize. My control variables are the initial inlet species concentration, initial fluid velocity (which in this case dictates the volumetric flow) and the applied voltage. I've defined the lower and upper bounds yet I keep getting this error message using the BOBYQA solver, yet it appears to go through just fine trying Nelder-Mead. What baffles me is that Nelder-Mead works even if I don't clearly specify the control variable limits. Any suggestions?


0 Replies Last Post Jul 13, 2023, 1:02 a.m. EDT
COMSOL Moderator

Hello Uriel Pedroza-Medina

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