## Fluids

#### Calculating the Heat flux

• snp1009
Subscriber

Hello all

I'm currently using HFSS to find the dissipated power in 3 metal rings as seen in the figure below

I'm feeding the 3D model with a circuit and I found the dissipated power on the outer rings to be 18.67 W and the dissipated power on the middle ring to be 16.74 W

I tried to use Ansys workbench to get the thermal behavior for the 3 rings, unfortunately there is no direct way to link the (circuit and 3D model ) to the transient thermal analysis in workbench.  What I was trying to do is to figure out the dissipated power using field calculator in HFSS and then divide the power by the surface area of the ring to get the power density. I checked the units for the heat flux which is W/m^2 an then I ran the model and I didn't give me the desired temperature distribution. Can someone tell me how to calculate the heat flux based on my design and power.

• peteroznewman
Subscriber

Hello snp,

I would think that the power calculated in HFSS is represented in Transient (or Steady State) Thermal as an internal heat generation in the material, which is in the units of W/mm^3

That heat flows out of the material through convection at the surface to the ambient air.  You need to specify a film coefficient for the convective heat transfer, and pick the faces that the solver will use to transfer the heat from the coils to the ambient air.

Regards,

Peter

• snp1009
Subscriber

Hello Peter

Thanks for your response. I think that when I link the HFSS design to the transient thermal analysis in workbench, the data is described as heat flux as you can see in the picture below.

My question is how can I export the imported heat flux data as xml file ?