Average power on a surface

[nibola]

Hello

This might look a silly question, but I don't know the answer.

I am using Workbench 14.0, steady state thermal analysis. In my model, I have some power in one surface and I would like to know which is that power. As a solution I have the total heat flux, but the units are W/m2 and I am looking for the total amount of W. That would be like an integration or average of the total heat flux.

Is there any way I can get this value?

Thank you very much

 

[flash3780]

In a word... in Workbench... no. At least not as far as I know. Though Workbench is under rapid development, so they may have added that feature and I might just not be aware of it...

However, you can flip over to ANSYS/APDL and output the power entering/exiting a surface by querying that property from the elements (SURF151/SURF152). When you apply a thermal boundary condition, ANSYS/Mechanical will skin the surface with "surface effect elements", which can output all sorts of handy results via ETABLES.

See the available element output options in the ANSYS help file for SURF151/SURF152 elements.

I think that the following APDL will get you what you're after:

CMSEL,S,MY_SURF,ELEM    !SELECT COMPONENT W. SURFACE ELEMENTS ON DESIRED SURFACE (CALLED A "NAMED SELECTION IN WORKBENCH")
ETABLE,MY_HEAT,SMISC,2  !CREATE ETABLE W. ELEMENT HEAT FLOWS
SSUM                    !SUMS THE ELEMENT OUTPUT VALUES IN YOUR ETABLES

If you're doing any more than a simple heat transfer analysis, I'd really recommend using ANSYS/APDL. My experience with Workbench was that it is currently far from adequate to deal with the all of the variables that are required for a proper heat transfer model.

 

[nibola]

Hi Flash3780.

Thank you very much for your answer! I am quite a new user in Ansys and don't know much about APDL.

I have been using APDL in Mechanical in a "Command", to put power to a surface or to get the displacements from other surface. But that code was written by someone else at work.
I tried your APDL but don't know exactly how it works. I been looking in help but couldn't figure out. CMSEL I think it is clear how it works, but not sure about ETABLE and MY_HEAT your are using...
Also, where should I get my results?

Sorry if these are very basic questions!

Thank you again.