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## Simulation CFD

Active Contributor
Posts: 51
Registered: ‎08-13-2013

# Heat Dissipation

202 Views, 3 Replies
11-12-2013 11:35 PM

Hello CFDexperts,

Pls help me in this regard,

Problem Definition:

"A box filled completly with vacuum and tube/pipe with water extends its way outside of either side of box and a chip has been placed on top of tube. -Water inside tube acts as cooling for chip by means of conduction and water is not exposed to vacuum inside entire box.

To Know:

1. Can we define vacuum in CFD & how ?

2. How to find Heat Dissipation in Vacuum ?

Thanks-n-advance

Kind Regards,

Ajay.S

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Product Support
Posts: 645
Registered: ‎08-24-2011

# Re: Heat Dissipation

11-13-2013 07:27 AM in reply to: ajay.s

1. Can we define vacuum in CFD & how ?

This is going to have a very low conductivity and density.  You will assume that the flow in the vacuum is stagnant.

2. How to find Heat Dissipation in Vacuum ?

There will not be very much conductivity through the vacuum so the primary mode of heat transfer from the chip to the housing is going to be radiation.  The rest and probably most of the energy is going to be captured by the water pipe.

Considerations:

Can we ignore the vacuum and use radiation boundary conditions on the outside of the chip?

Can we assume that all the energy is transferred to the water and ignore and other paths of heat transfer?

Royce Abel
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Active Contributor
Posts: 51
Registered: ‎08-13-2013

# Re: Heat Dissipation

11-13-2013 09:08 PM in reply to: Royce_adsk

Dear Royce,

I appreciate your response. Many Thanks

Here,

1. The condition tested in reality is through Vacuum and I want to know whether CFD can handle /Define Vacuum pls?

2. Yes here only pipe is the element where heat dissipated from Chip is transferred and NOT contact with water exist.

Kind Regards,

Ajay.S

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Active Contributor
Posts: 51
Registered: ‎08-13-2013

# Re: Heat Dissipation

11-13-2013 09:28 PM in reply to: ajay.s
Dear Royce,

Please keep this post open until we get more clarity on this and could be helpful for new beginners who were looking for same.
Many Thanks for your support
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