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Member
AlphaVladim
Posts: 4
Registered: ‎02-03-2014
Accepted Solution

Making a heat pipe.

246 Views, 6 Replies
02-03-2014 02:41 PM

Hello autodesk users!

This is my very first post here, so please be kind :smileyhappy:.

 

Is there any way to simulate / create a copper heat pipe ? I need it as i am building a cpu cooler.

 

Few additional questions:

Maybe i am using the wrong software for my needs ? 

Can i simulate my CPU cooler's performance with Autodesk Simulation CFD?

 

Please note i am a begginer with CFD Simulation and Inventor. 

Thank you!

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Product Support
wildej
Posts: 782
Registered: ‎08-25-2011

Re: Making a heat pipe.

02-05-2014 12:00 AM in reply to: AlphaVladim

Hi AlphaVladim,

 

The best way to approach this (for straight pipes) is to modify the copper material and create a new material. Increase the conductivity of this new material in the axial direction by 1000x, leaving the other directions as copper.

 

You should be able to investigate a CPU cooler's performance, yes.

 

Kind regards,

Jon



Jon Wilde
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Member
AlphaVladim
Posts: 4
Registered: ‎02-03-2014

Re: Making a heat pipe.

02-06-2014 01:33 AM in reply to: wildej

I have tried doing a quick project, just to acomodate myself with CFD simulation. I tried to copy the tutorial project i found here : http://help.autodesk.com/view/SCDSE/2014/ENU/?guid=GUID-42DF117E-5D9B-4300-838E-B2DC6A22BF7D .

First try worked very well, i had only one chip with a total heat generation of 10W, as in my second try. But my 2nd attempt has very unappropiate values.

 

Pic1.png

 

Here is first project :

 

Pic3.png

 

Thanks!

 

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Product Support
wildej
Posts: 782
Registered: ‎08-25-2011

Re: Making a heat pipe.

02-06-2014 01:37 AM in reply to: AlphaVladim

Hi,

 

It is hard to tell what is wrong by these images.

 

 

Do you have a proper inlet and outlet? Really we need a cylinder of air on each, roughly 5x the diameter in length.

What are your Boundary Conditions?

 

Kind regards,

Jon



Jon Wilde
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Member
AlphaVladim
Posts: 4
Registered: ‎02-03-2014

Re: Making a heat pipe.

02-06-2014 03:29 AM in reply to: wildej

I have attached the CFD support file. Hope it helps.

 

I have followed exactly the steps shown in the tuturial i have mentioned.

Here are pictures of my inlet and outlet boundaries.

 

Pic1.png

 

Pic3.png

 

Please excuse my bad english!

 

Thanks again!

 

Edit: Transient solution mode seems to work better, max temperature reached is 34 after 50 time steps.

But what's the difference between transient and steady state modes ?

 

Edit 2 : I have found something interesting. http://usa.autodesk.com/adsk/servlet/ps/dl/item?siteID=123112&id=17523563&linkID=18154757 . I will try and post the results.

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Product Support
wildej
Posts: 782
Registered: ‎08-25-2011

Re: Making a heat pipe.

02-06-2014 03:59 AM in reply to: AlphaVladim

Do not use transient unless you are looking at something changing over time. Steady state gives you a point in time (think of it as what would happen if you run transiently for an infinite time).

 

Thicken your fan - so it is like a fan in reality, roughly where the fan blades would be. You also need a refined uniform mesh on it - 5x elements from inlet to outlet.

You have an abs part right next to the fan - I suspect this is really meant to be the fan.

Note that you also have some metallic shaped air parts around yout chip.

 

Extend inlets and outlets. 5x diameter for the inlet - your outlet should be about 10x longer.

 

You can also suppress the case from the mesh, unless you are lookin at conduction through it (which you are not in this case)

 

Hope that helps.

 

Kind regards,

Jon



Jon Wilde
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Member
AlphaVladim
Posts: 4
Registered: ‎02-03-2014

Re: Making a heat pipe.

02-06-2014 06:57 AM in reply to: wildej

Got it! I will redesign the while thing and start again.

But what is "Advection"? You can find it under Solve - > Solution Control - > Advection. Wich one of them should be thicked for steady state mode ?

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