Learning Forum

[Nikopar10]

Hi everyone, i hope everyone is doing great through this rough time.

I'm doing a conjugate (thermal and fluid dynamic) study on a metal foam representative elemental volume (RVE) which would be placed on a fluid domain (air). The experiment consist on a heat flux placed on the bottom face (face whose normal vector has the same direction of -Z) and an air flow going forward on +X direction. The expected result is a conduction through the metal foam and convection between the foam and the air.

 

i'm using ANSYS academic version, that's the reason the mesh is the way it is.

i'm rather confused with the boundary conditions and, maybe, about the named selection i have to set. 

I set the following named selection and boundary condition:

• "inlet": velocity inlet=0,5 m/s 


• "outlet": Pressure outlet, gauge pressure=0


• "slippery walls" (the ones that limit the domain): shear stress= 0 on all the compenents, and a convection condition


• A worksheet that selects all faces at Z=0: heat flux at 100 W/m^2

the model was Steady, Pressure-Based, Viscous (Realizable k-e), Energy On, the solution method used is Coupled.

the simulation was planified to calculate 2000 iterations but it clearly failed so i stopped the calculations.

i hope you can help me with this or advice me. I'm this close ->...<- to end these study and getting my mechanical engineering degree!

Regards!

 

Nicolás Parodi Saldivia

 

[Rob]

The mesh is far too coarse in the main section of the channel: this needs to be refined. Also, how do you expect heat to get to the foam? 

[Nikopar10]

Hello! thank for the reply!

thanks for the advice about the mesh. About the heat flux, the experiment is trying simulate de interaction between a CPU and a heatsink, so i expect to simply set a heat flux entering the foam from the bottom, being sincere I don't know how to set a heat flux with those characteristics.

[osm0655]

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hi Nikopar10 how did sketch metal foam

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[Rob]

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It may be the result of a micro-CT scan or subtracting multiple randomly positioned spheres (bubbles) from a block.

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