Constant volume kept during DAKOTA-Optimization

[Constant volume kept during DAKOTA-Optimization]

Hi Mr. Heinrich

 

Thank you very much for your reply, your answer is very helpful to me.

 

I did this series of work on a computer cluster.

 

I use 3d modeling software (such as FreeCAD, openSCAD) to control a series of parameter variables to obtain the geometric model. Then, I used DAKOTA and OpenFOAM to carry out subsequent optimization and numerical simulation tasks.

 

I know CAESES is a very excellent optimized design software. I wonder if it will work on Linux based on the command line. Because we plan to build an optimized simulation service platform with some open source software.

 

 

The DAKOTA and OpenFOAM coupling process is:

 

1. The DAKOTA internal optimization algorithm gives a set of variables according to the range of parameter variables provided;

 

2. Parametric modeling by modeling software;

 

3. OpenFOAM numerical simulation to obtain the lift/drag ratio;

 

4. All geometric models and their mechanical properties can be obtained.

 

 

Now, I want to add the fixed volume constraint of the geometric model to processes 1 through 3. There are probably two ways to do this:

 

1. In process 2, the volume of the geometric model is obtained through the volume command tool in the 3d software. if the volume satisfies the condition, then process 3; if the condition is not met, then other variables in the variable set are selected for modeling again;

 

2. Create a mathematical expression that can solve the volume of any geometric model (perhaps by code) and put it in Process 1, and all the geometric models we get will satisfy the volume constraint.

 

Note that all variables in this process are generated by DAKOTA.

 

Now, I don't know if my idea is feasible. Do you have any suggestions for this?

 

Best regards,

Xuxiang

 

[Constant volume kept during DAKOTA-Optimization]

Hello :)

 

I want to optimize a underwater body with defined volume to minimize drag. Therefore we want to input our body (more than 10 parameters) in a DAKOTA search engine.

After definment of an equality constraint and running the optimization I got no matching designs that fit to this given volume.

 

To compare those volumes I added a parameter "isVolume" with <BRep>.getVolume() as a value. Than another parameter "destVolume" is put together with "isVolume" in the equality constraint.

 

So my problem is basically to get the DAKOTA-algorythm to work with this definition of constant volume.

 

 

 

Thank you,

Felix

Hi Mr. hjkl 3ff

 

I encountered problem that very similarly to you. I get different underwater-glider-bodies (with different parameters) using DAKOTA-algorithm, then i acquire drag/lift coefficient in openfoam. 

But i do not know how to get those parameters with constant volume.

 

Can you help me to solve this problem? Or, do you have any ideas?

 

Thank you very much.

Xuxiang