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-   -   [DesignModeler] Equation Driven Curve - URGENT (http://www.cfd-online.com/Forums/ansys-meshing/116692-equation-driven-curve-urgent.html)

daysley April 23, 2013 08:03

Equation Driven Curve - URGENT
 
Hi Again

I wondered if anyone could give me any help with ansys design modeler please. my problem is i need to create an equation driven curve for an airfoil/ hydrofoil then use optimisation to optimise torque on a vahkt. firstly i have no idea where to find an equation driven curve in designmodeler (ive tried to parameterise splines, lines but no luck).

however, i have modeled the geometry in solidworks, created a surface and imported the geometry into workbench but my parameters are not exported and the airfoil is orientated incorrectly??

basically all i want is a 2d curve that i can interchange with my existing fixed Naca00xx profile and run an optimisation sim

any help is greatly appreciated, thanks in advance!!

Sam

daysley April 24, 2013 12:54

Anyone?

i have imported geometry dimensions today but my equation for the equation driven spline in Solidworks is not showing up which is a bit useless because that's what i need

any help is great

thanks in advance

moloykb April 29, 2013 04:32

use the 3D curve feature to generate the curve

daysley April 29, 2013 05:42

thanks for the suggestion Moloy, unfortunately the 3d curve requires point selection or a coordinate files, whereas i was looking for a curve driven by a parametric equation so i could alter the thickness and camber through the parameters.

I found a work around in the end,

In Solidworks i created the equation driven curve then in a sketch (not in global variables>this is done by dimensioning construction lines) i dimensioned the variables i needed (thickness ratio and chord length) and used the prefix DS_ in the name box. this allowed me to use these values for the curve equations and also import them and indirectly change the equation of the curve from Workbench.

pretty disappointed ANSYS doesn't have the technology to do this unless i haven't come across it yet, but this was a successful alternative hope it helps others in the future.

Thanks for your help Moloy

Far April 29, 2013 05:58

I am also learning DM, but I have an idea. you can try scripting ...

daysley April 29, 2013 06:00

Far, i don't think i am familiar with scripting? is this a difficult approach?

Far April 29, 2013 06:09

definitely coding (even simple scripting) needs more effort... But I am sure you can learn it

daysley April 29, 2013 09:33

I'll have to have a look into scripting and coding then see where i get, thanks Far ill see how i get on

fedefrance February 27, 2014 10:54

Hi Daysley,

I have the same problem you have. I would need to perform an optimization of a 2D aerodynamic profile and I would like to use a prametrized curve, like a B spline or a Bezier curve.

I was thinking about inserting the curve by scripting into design modeler or ICEM but I don't know from where to start.

Do you have any suggestion? Did you manage to solve your problem?

daysley March 3, 2014 14:42

Quote:

Originally Posted by fedefrance (Post 477135)
Hi Daysley,

I have the same problem you have. I would need to perform an optimization of a 2D aerodynamic profile and I would like to use a prametrized curve, like a B spline or a Bezier curve.

I was thinking about inserting the curve by scripting into design modeler or ICEM but I don't know from where to start.

Do you have any suggestion? Did you manage to solve your problem?

Hi fedefrance

this was what i hoped to do also, however i had no experience with python so decided scripting wasnt the way i was going to go. instead i used solidworks to fully parameterise an equation driven curve and then export the variables (such as chord, thickness etc) to ansys using the prefix DS.

see here for details

https://forum.solidworks.com/thread/64546

you can then import this geometry into designmodeler. this is the only approach i found that worked well, but only allows symmetrical naca profiles to be used. unsymmetrical ones may take a little playing around equation wise, but they could work??

hope this helps

fedefrance March 4, 2014 05:44

Hi Daysley,

Thank you for your suggestion, I will give it a try. Also I found another approach which could work:

http://www.youtube.com/watch?v=6wQPeBpvwCk


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