Definition of FFD Design variables

Jim gigi · February 22, 2023, 00:02

Hello to all,
I'm currently trying to optimize the flap and slat angle of CRM-HL slice, and i've been using FFD_ROTATION to do the job, but was having poor results.

% FFD_ROTATION ( 18, Scale | Mark. List | FFD_BoxTag, x_Axis, y_Axis, z_Axis, x_Turn, y_Turn, z_Turn )

I know that x_Axis, y_Axis, z_Axis should be rotation axes.
Does anyone have any clue on the definitions of x_Turn, y_Turn, z_Turn ? or how can i set the rotation center of different FFD boxs ?

and I'm using SU2 v7.5.1

Thanks,
Jim.

pcg · February 23, 2023, 01:59

Hello,
I never used this before, but from what I see in the code x_Axis, y_Axis, z_Axis define a point on the line of rotation and x_Turn, y_Turn, z_Turn define the direction of the line (it is not clear if it needs to be a unit vector), then, the angle of rotation (in degrees) around this line is defined by DV_VALUE.

February 22, 2023, 00:02	Definition of FFD Design variables	#1
Jim gigi New Member jim Join Date: May 2022 Posts: 6 Rep Power: 4	Hello to all, I'm currently trying to optimize the flap and slat angle of CRM-HL slice, and i've been using FFD_ROTATION to do the job, but was having poor results. % FFD_ROTATION ( 18, Scale \| Mark. List \| FFD_BoxTag, x_Axis, y_Axis, z_Axis, x_Turn, y_Turn, z_Turn ) I know that x_Axis, y_Axis, z_Axis should be rotation axes. Does anyone have any clue on the definitions of x_Turn, y_Turn, z_Turn ? or how can i set the rotation center of different FFD boxs ? and I'm using SU2 v7.5.1 Thanks, Jim.

February 23, 2023, 01:59		#2
pcg Senior Member Pedro Gomes Join Date: Dec 2017 Posts: 466 Rep Power: 14	Hello, I never used this before, but from what I see in the code x_Axis, y_Axis, z_Axis define a point on the line of rotation and x_Turn, y_Turn, z_Turn define the direction of the line (it is not clear if it needs to be a unit vector), then, the angle of rotation (in degrees) around this line is defined by DV_VALUE. Jim gigi likes this.

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