Thermal analysis of a freezer

[sahinoz]

Hello everyone,
I was wondering if anyone can help me out or lead me to a starting point of modeling a freezer. What I want to do is that model a "chest freezer" where I can analyse the heat flow from inside of the freezer to outside world. My main goal is to analyse the heat flow with several different gasket profiles and compare their thermal conductivities. Any comment is highly appreciated.
Thanks

 

[JKEngineer]

Since no one else has responded, I will take a stab at this.

I am not completely clear on your problem as posed... but:
I am assuming you want to use different gasket designs where you know the thermal conductivity of the materials, but not the apparent thermal conductivity of the assembly.

I think you only have to model the gasket and immediate surroundings, not the whole freezer. Set the interior conditions and exterior conditions, simulate the system, get the heat flow through the area of interest. Repeat for different designs.

Does this address your question?
Jack


Jack M. Kleinfeld, P.E. Kleinfeld Technical Services, Inc.
Infrared Thermography, Finite Element Analysis, Process Engineering

http://www.KleinfeldTechnical.com

 

[JStephen]

Is this a freezer like a refrigerator, IE, powered? Or is this an ice-chest, like you'd take camping?

If it's an ice chest, fill it mostly full of chilled water (with no ice), put it in whatever environment is of interest, and measure the rate at which the temperature increases. You should be able to do some similar test with an electric freezer. Either test would be somewhat approximate, but then again, the ambient temperature and configuration of the contents will just be assumed anyway, so that should be close enough. What this will tell you is the overall rate of heat gain in the thing. IE, you no longer have to model the whole unit, just the gasket, as noted above.

For the gasket...that would get harder. Assume ambient temperature on one side of the gasket, assume freezer temperature on the other side. Perhaps use FEM, or whatever analytical means are available for the gasket itself.

Once again, if you actually have the gasket (IE, analyzing different available gaskets, not inventing a gasket), you could run tests on them similar to the above. Perhaps make a box that splits in half, with the gasket to seal it up.

I suspect that what would be more important would be how long-lasting and tight-sealing the gasket was. A gasket that insulated wonderfully but dried out and let air leak after a few years wouldn't be worth much.

 

[gwolf]

I believe this is an example of 1D heat transfer and you don't need to use FE to solve it for a steady state condition. Try a good heat transfer text like Holman.