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-   -   Solid-Solid Heatflux of Moving Roller (http://www.cfd-online.com/Forums/cfx/102081-solid-solid-heatflux-moving-roller.html)

Torque_Converter May 21, 2012 21:21

Solid-Solid Heatflux of Moving Roller
 
In the image included the disc is rotating about its axis in a moving fluid environment at 3000 RPM. As the rim passes the stationary block it is heated at this contact by a heat flux of 6.44e7 W/m^2. I have everything modeled as I would like, however, CFX insists on giving the rotor a wall boundary condition with either adiabatic, constant temp, heat flux or heat generation condition.
I only want the disc to pick up and shed heat via the contact flux and the convection about it. How can I do this?

Thanks

http://imgur.com/QNrYO

PS: If this solid solid interface is not possible, how could I have this stationary heat flux source, while the disc rotates by it and picks up heat briefly?

ghorrocks May 22, 2012 06:54

You can heat the boundary using a source term. Source terms can be applied on boundaries, interfaces, subdomains, points - just about anywhere.

Torque_Converter May 22, 2012 17:02

I think the issue it is having is that the roller boundary is a wall and as such CFX wants to assign it to be adiabatic or have some constant heat flux/generation, when all it should do is be a passive rotating component picking up and shedding heat from the block and surrounding fluid.
I have assigned on the block where it contacts the roller to have a heat flux, but I couldn't do this on the entire rim of the roller since it is rotating and not always receiving this heat flux.

ghorrocks May 22, 2012 20:14

I think I see your question now - you want a solid/solid interface when the wheel contacts the block, and a solid/fluid interface when the wheel is not in contact with the block. I am not sure but I suspect you cannot do this. You need to define two interfaces to do this with the outer rim of the wheel being in both interfaces, and a surface cannot be allocated to two interfaces.

If you define the wheel as a solid/fluid interface and use the non-overlap conditions to generate your heat at the block that would work. But it will not be coupled between the wheel and the block.

Torque_Converter May 22, 2012 20:22

I think you're right, it's just not going to be possible since I'm trying to make the rim of the wheel part of 2 interfaces. What I may move on to is using CFX purely to find the convection coefficients due to rotation since I can easily, without the solid, assign a rotating wall condition, and then try to place these in mechanical. I've seen the ability, using APDL to have the rotating thermal contact patches.


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