AoA derivative for NACA0012?

Ry10 · April 15, 2016, 12:53

I want to find the adjoint derivative of drag with respect to AoA for the NACA0012. I found the Sens_AoA in the history.csv file when I run the ADJOINT using the QuickStart files. But when I do finite difference this value is not even close to what the finite differences says the derivative should be. Is this the way to get the AoA derivative or is there a better way? There are lots of design variables available but I can't figure out a way to get the derivative of angle of attack.

Thanks!

fpalacios · April 22, 2016, 02:15

Hi,
I'm using the sensitivity with respect to the AoA and the error compared with FD is acceptable. Are you sure that you are using 1/rads or 1/deg in both numbers? as you know, the factor is 57.2957795131. as far I remember Sens_AoA uses 1/rads

Best Regards,
Francisco Palacios

Ry10 · April 28, 2016, 16:57

That did the trick. I thought it was in 1/deg not 1/rad. Thanks!

April 15, 2016, 12:53	AoA derivative for NACA0012?	#1
Ry10 New Member Ryan Barrett Join Date: May 2015 Posts: 15 Rep Power: 10	I want to find the adjoint derivative of drag with respect to AoA for the NACA0012. I found the Sens_AoA in the history.csv file when I run the ADJOINT using the QuickStart files. But when I do finite difference this value is not even close to what the finite differences says the derivative should be. Is this the way to get the AoA derivative or is there a better way? There are lots of design variables available but I can't figure out a way to get the derivative of angle of attack. Thanks! kmandar likes this.

April 22, 2016, 02:15		#2
fpalacios Super Moderator Francisco Palacios Join Date: Jan 2013 Location: Long Beach, CA Posts: 404 Rep Power: 15	Hi, I'm using the sensitivity with respect to the AoA and the error compared with FD is acceptable. Are you sure that you are using 1/rads or 1/deg in both numbers? as you know, the factor is 57.2957795131. as far I remember Sens_AoA uses 1/rads Best Regards, Francisco Palacios kmandar likes this.

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April 28, 2016, 16:57		#3
Ry10 New Member Ryan Barrett Join Date: May 2015 Posts: 15 Rep Power: 10	That did the trick. I thought it was in 1/deg not 1/rad. Thanks!