## General Mechanical

#### heat distribution inside solid body

• apfen42
Subscriber

Hello everyone!

I am doing a 2D simulation.(you can see it in the image)
I want to simulate 2 solid bodies, with different velocities. they are only in contact in a a small region at the interface between the bodies. In this region there is a heat source withh a specific amount of heat. I want to simulate how the heat gets ditributed inside the solid bodies depending on the difference in their velocities.
I attached an image of my problem.

How should i do this?

Also should I use static structural or static thermal for this? or should i combine both?
Thank you!!

• peteroznewman
Subscriber

Hello,

You should make the frame of reference the bottom body and let that be stationary, then assign a velocity to the top body of v1-v2.

What is that black rectangle?  Is that a third body?  Is that the body that is at some high temperature and significant thermal mass? It the transient thermal model you want to track how the heat flows out of that mass and into the blue and grey bodies?  What velocity is that black rectangle moving at?

Can we assume that no heat flows between the blue/grey bodies, except through the black body?

I'm not sure how to build this model. You might need APDL code to make this work. I put a Transient Structural and Transient Thermal system and tried to use System Coupling, but got an error.  I got the same error with a Static Structural also.

I will be interested to read what the experts have to say, but help them out by answering my questions.

Regards,

Peter

• apfen42
Subscriber

Hi Peter,

thanks you for your interest, sorry for not explaining it clearly enough.

So okay the black box was just my way of showing you guys the region where the heat exchange takes place. so actually there is no body between the two rectangles. So yes, it can be assumed that except for the black region there is no heat flux between the bodies.

The region represents a small x-distance in the bottom body where the connection between both rectangles takes place.

And what i want to simulate is, if theres a heat generation at that region, how the temperature rises and is distributed inside the bodies.

regards!

• peteroznewman
Subscriber

You might get something from this video.

Regards,

Peter

• apfen42
Subscriber

Hi,

thanks for the video. indeed my actual problem is to get the heat distribution and the thermal subsurface stresses due tue frictional heating in a hertzian contact between 2 parallel cylinders (in 2D). My first attempt to simplificate the problem was probably not very good.

So now I tried it with a semicircle rolling over a halfspace with frictional contact betwen the bodies. I placed a pressure on the semicircle and a fixed support at the bottom of the halfspace.

Somehow the results dont show a temperature rise during the rolling over the surface.

Maybe someone know a better way to simulate the heat distribution due to frictional heating on hertzian contact.

Thank you so much!