Parametric study in floefd
 

Hi,

I am doing Heatsink Design that suits for my LED. I want to do DOE by changing the number of fins and Dia of the HS.

This could be done using Parametric study in floEFD. I don't know how to use this study.

Can anyone please suggest me any tutorial files to refer.

FYI...I am using Floefd in Solidedge

Pandiyan

H Pandiyan,

unfortunately, the parametric study doesn't work for CAD parameters as the moment in Solid Edge. This is a limitation with the API from the CAD system but we are working on it together with the SE team to fix this and enable CAD parameter control with FloEFD also for SE.
The best way to handle this now is to manually create a variation of heat sinks and use the alternate assemblies to switch between them and simply clone the projects onto those new geometry variants that will show in the top part of the FloEFD tree. Not the ideal case, I know, but the only quick way of doing it within FloEFD and SE.
Another way would be to leverage the API of FloEFD and SE. This way you can control it from the outside like from Excel and alter the CAD parameters, then run the simulation again and do that in a loop with a range of parameters you can specify.
A third option would be to use the External Optimizer feature in the parametric study menu where you can link FloEFD to an external optimizer (maybe you have one already in-house, use an opensource optimizer or Siemens also offers HEEDS). The optimizer then can control the CAD parameters and restart the simulation for a range of simulations and optimizes the CAD model for a specific target or multiple targets such as reduced pressure loss and low temperature.

Regards,
Boris

Hi Boris,

Thanks for your help. I will try these. Also can you have any work flow (instructions/tutorials) for these methodologies?

Pandiyan

Hi Pandiyan,

1.
I think the first one is quite simple. You probably know how to create multiple variants of a geometry with the alternate assemblies. Each of the variants of the assembly will show as a geometry variant in the FloEFD window with the project tree below. You can right-click the project and say you want to clone it and select a configuration the clone of the first project should be created on. This you repeat for all the variants that don't have a project yet.

The second and third are a little bit trickier as you will need some programming experience.

2.
FloEFD comes with an API that you can use to start and stop simulations from either out of Excel or any other VBA or VC++ interface you programmed. It will require also to change the geometry of the CAD model from outside the CAD system. I'm not an expert in doing that for SE but I'm sure there is a way for that as well with an API.
So an Excel table could contain for example a min and max height of the heatsink's fins and the script could change the CAD model to the min height initially and run the FloEFD project. Then at the end, you can get key values such as CPU temperature that sits underneath the heatsink through the API by asking for the corresponding goal and store it somewhere in the spreadsheet. You can then change the CAD parameter in a specific step such as 2mm bigger and run the next simulation on the new geometry and repeat that until it has reached the max height. This is just an example of how it works roughly.
As for the FloEFD API, there is a help in the software itself if you go to the Flow Analysis Tab and on the right side there is a ? with "Topics" in which you find a help about the API. You will need to install the API as well from the Installation source (download or DVD) in the folder FloEFD-x64 there is another folder "APISDK".
Once you've done that, there is a VBA and VC++ example installed with the API in the API installation folder.

3.
This might be the trickier part as it depends on what you want to use. Existing optimizers such usually have a good user interface, but the opensource optimizer or the own script will require again some more programming. The own script is basically similar to the VBA example mentioned above but less with an Excel sheet to control it but simply the XML file that handles the communication and any calculation between the two FloEFD simulations. So you would ask for the results and store them somewhere and then increase the value and let the next simulation start. All within the XML script.

For more information, I would ask you to contact support and let them provide you with an example of how it could look like.

Regards,
Boris