Calculating Heat Transfer Through Sandwich Materials

[Buns_of_Steel]

Hi,

I'm looking for some help regarding heat transfer through some sandwiched materials.

We have a pneumatic cylinder with the stainless steel 303 cylinder rod attached to a block of aluminium 6082 t6 50mm high x 40mm wide x 10mm deep. This block is attached to a block of polyurethane, shore a70 70mm high x 40mm wide x 10mm deep which is then attached to a block of copper c101 70mm high x 40mm wide x 30mm deep. The copper block is heated to a temperature of 250 degrees Celsius. A cross section of the layout is shown below.

What we want to do is treat the arrangement as simply as possible i.e. ignoring the fasteners, holes etc and calculate the heat transfer through the copper, polyurethane, aluminium and into the cylinder rod and get a rough idea of what the temperature will be in the cylinder rod would be.

I'm at a bit of a loss as to where to start with this.

If anyone could help with a basic procedure of how to tackle this problem and what the relevant equations are it would be much appreciated.

Cheers

David

 

[gmax137]

Unless the rod can transfer heat to the cylinder, and the cylinder to the ambient air, the rod (and the other components) will heat up until it all reaches the temperature of the copper block. You'd need a lot more information to predict the rod temperature, and that would be assuming a steady-state condition. If the copper block temperature varies in time, the problem is even harder to solve. It might be faster to build one and measure the temperature.

Either way, this one should be moved to the engineering sub-forum.

 

[CWatters]

You would need to know the thermal resistance between the piston/rod and ambient via the cylinder. I agree easier to build it and measure.