Conjugate Heat/ thermal elastic ?
 

Hi All,

I hope you guy don't mind an off topic question. I am helping my wife with a problem (yes she is a grad student --experimentalist) that involves solving a conjugate heat transfer problem and as well as a themal elastic problem (a nonisothermal fluid in contact with a two-layer solid wall). I have done the conjugate heat transfer part with my own code and I was planning on doing the themal elastic analysis for the two layer solid portion of the problem as a post analysis.

My question is not quite CFD related but I am posting here because I read this COOL forum. Is there any good resources that discuss how to do the themal elastic analysis? --Jeff

Re: Conjugate Heat/ thermal elastic ?
 

What exactly do you mean by "thermal elastic analysis"? It's not very specific. Do you mean you want to figure out the deformation of the solid given the temperature distribution imposed by the fluid on the solid surface?

Re: Conjugate Heat/ thermal elastic ?
 

Sorry about being unclear.

Yes, that is what I want to do. Knowing a reference state with no stress at a temperature T_ref, I would like to get an idea of the stresses cause by thermal expansion of the two solid materials. --Jeff

Re: Conjugate Heat/ thermal elastic ?
 

Jeff,

Each material has a characteristic coefficient of thermal expansion (units: meter/meter/Kelvin). You would need to use that to solve for the strain using a finite element formulation.

Our CFD-ACE+ solver has a FEA stress module coupled directly to the FVM flow / heat / etc. solver. If you go to our web page <www.cfdrc.com>, click on "Application" and then on "Ink Jets" you can see an example that I did about a year ago. If you scroll down the page a bit you'll see a title "Bimaterial Cantilever Beam....". Take a look at the animation. The beam has a heater layer and a ceramic layer with different coefficients of thermal expansion. When the heater is activated, they each would normally grow different amounts, and the net result is bending that kicks out a droplet.

Regards, Alton

Re: Conjugate Heat/ thermal elastic ?
 

(1). I think, it is called "thermal stress analysis". It is fairly standard in stress analysis.

Re: Conjugate Heat/ thermal elastic ?
 

thermomechanical

Re: Conjugate Heat/ thermal elastic ?
 

(1). I am having difficulty in finding the word "thermomechanical". (2). Is it another word for thermal stress analysis?

Re: Conjugate Heat/ thermal elastic ?
 

your problem is pretty standard in finite element structural analysis. Since you know the temperature on the surface you can solve for the temperature in the solid then apply this to the structural model and find the deformation due to the thermal field. I guess you can do the first part since you have done the conjugate heat transfer. Can you give me an email about this problem? It sounds interesting.