Objective functions

khavart · June 10, 2019, 10:02

Hello,

I post this thread because I have some questions about Objective functions available in SU2.

My goal is to optimize a Nozzle in order to have a uniform Mach number at the outlet and minimizing losses.

First of all I've seen that many objective functions were implemented but I don't know what these functions exactly mean. For example what represent Efficiency and Surface_Mach functions ? Those could be interessant for me.

And if there are no objective functions already implemented in SU2 for my problem, do you know if it is possible to implement custom objective function ? (I don't know C langage at all)

Thanks,
Kevin

nitish_anand · June 10, 2019, 12:01

Hey Kevin,

You can use ENTROPY_GENERATION. To use this objective you need to set up your nozzle as Turbomachinery problem. And is not difficult, look into the tutorials.

Thanks,
Nitish

khavart · June 11, 2019, 04:32

Hey Nitish,

Thanks for your answer, Trying to do this I've have a segmentation fault (core dumped), is there any change to do in my mesh file to be able to use turbomachinery settings ?

And have you an idea for the uniformization of the mach number ?

Thanks,
Kevin

nitish_anand · June 11, 2019, 08:01

Hey Kevin,

You need TURBOMACHINERY_KIND and TURBOMACHINERY_MARKERS() in config to enable turbomachinery features.

By uniformation, I guess you mean averaging kinds, yes there are several implemented. Please look into the tutorials or config_template and you will find them.

Thanks,
Nitish

June 10, 2019, 10:02	Objective functions	#1
khavart New Member kevin havart Join Date: Jun 2019 Posts: 8 Rep Power: 7	Hello, I post this thread because I have some questions about Objective functions available in SU2. My goal is to optimize a Nozzle in order to have a uniform Mach number at the outlet and minimizing losses. First of all I've seen that many objective functions were implemented but I don't know what these functions exactly mean. For example what represent Efficiency and Surface_Mach functions ? Those could be interessant for me. And if there are no objective functions already implemented in SU2 for my problem, do you know if it is possible to implement custom objective function ? (I don't know C langage at all) Thanks, Kevin

June 11, 2019, 04:32		#3
khavart New Member kevin havart Join Date: Jun 2019 Posts: 8 Rep Power: 7	Hey Nitish, Thanks for your answer, Trying to do this I've have a segmentation fault (core dumped), is there any change to do in my mesh file to be able to use turbomachinery settings ? And have you an idea for the uniformization of the mach number ? Thanks, Kevin Last edited by khavart; June 11, 2019 at 06:33.

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June 10, 2019, 12:01		#2
nitish_anand New Member Nitish Anand Join Date: Sep 2016 Location: Netherlands Posts: 12 Rep Power: 10	Hey Kevin, You can use ENTROPY_GENERATION. To use this objective you need to set up your nozzle as Turbomachinery problem. And is not difficult, look into the tutorials. Thanks, Nitish

June 11, 2019, 08:01		#4
nitish_anand New Member Nitish Anand Join Date: Sep 2016 Location: Netherlands Posts: 12 Rep Power: 10	Hey Kevin, You need TURBOMACHINERY_KIND and TURBOMACHINERY_MARKERS() in config to enable turbomachinery features. By uniformation, I guess you mean averaging kinds, yes there are several implemented. Please look into the tutorials or config_template and you will find them. Thanks, Nitish