[Ryan.]

Hi,

it may be a basic question but I'm confused about the usage of "DV_PARAM". We are already defining the design variables in "DEFINITION_DV", so why would we need to define "DV_PARAM" and what's it used for? For instance, when we have DV_PARAM= ( 1, 0.5 ) what are "1" and "0.5" representative of?

Thanks.

[fpalacios]

Hi Ryan, this is a very good question.
DEFINITION_DV is only used by the shape_optimization.py script. In other words SU2 uses DEFINITION_DV to specify all the design variables in your optimization problem. As you can see, DEFINITION_DV is a combination of the kind of design variable, the scaling factor, where are you going to apply the design variable, and a definition of the design variable (everything is there).

On the other hand DV_PARAM is only used in case you want to manually deform a computational grid using SU2_DEF. if you manually define DV_KIND, DV_MARKER, DV_PARAM and DV_VALUE you would be able to apply that particular deformation to the surface. e.g. if you set
DV_KIND=HICKS_HENNE
DV_MARKER= ( airfoil )
DV_PARAM= ( 1, 0.5 )
DV_VALUE= 0.01

and execute SU2_DEF, then SU2 will apply the bump to the airfoil surface.

Long story short, DEFINITION_DV is for shape design and DV_PARAM is for grid/surface independent deformations in case you are interested.

Best,
Francisco

[Ryan.]

Originally Posted by fpalacios

Hi Ryan, this is a very good question.
DEFINITION_DV is only used by the shape_optimization.py script. In other words SU2 uses DEFINITION_DV to specify all the design variables in your optimization problem. As you can see, DEFINITION_DV is a combination of the kind of design variable, the scaling factor, where are you going to apply the design variable, and a definition of the design variable (everything is there).

On the other hand DV_PARAM is only used in case you want to manually deform a computational grid using SU2_DEF. if you manually define DV_KIND, DV_MARKER, DV_PARAM and DV_VALUE you would be able to apply that particular deformation to the surface. e.g. if you set
DV_KIND=HICKS_HENNE
DV_MARKER= ( airfoil )
DV_PARAM= ( 1, 0.5 )
DV_VALUE= 0.01

and execute SU2_DEF, then SU2 will apply the bump to the airfoil surface.

Long story short, DEFINITION_DV is for shape design and DV_PARAM is for grid/surface independent deformations in case you are interested.

Best,
Francisco

Thank you very much, Francisco, it answers all my questions