Insulation

[themaniac]

I have a system that I want to insulate.
I have several types of insulation avaliable and thus want to eveluate them.
I also have the time constant for the systems (which was determined from testing).
How do I go about incorperating the insulation properties to reflect the change in time constant without having to estimate things such as surface area, volume ect.

Also, does anyone know of a reasonable 2D or perhaps 3D software for heat transfer that is freeware/shareware??

Thanks again people.

 

[Tremolo]

themaniac,

I am wondering how you defined or measured your time constant.

For example, if you immersed an object in a surrounding fluid of a different temperature and then measured the temperature change of the object over time, your thermal time constant would be defined based on a convective heat loss. If you then insulate the object, the convective resistance from the object would be replaced by a conduction or contact resistance between the object and the insulation. So, it might be difficult to apply the measured time constant.

If you could provide more information on how you obtained the time constant, it would be helpful.

TREMOLO

 

[jmw]

Why do you want to insulate?
Three possible reasons each result in a different approach:
1) safety - to stop people injuring themselves by touching uninsulated plant or pipelines
2) energy efficiency/conservation - cost/benefit ratio important
3) to isolate the plant or process from outside thermal influences - very important with some instrumentation
The different objectives usually result in quite different insulation strategies and costs.

JMW

http://www.viscoanalyser.com

Eng-Tips: Pro bono publico, by engineers, for engineers.

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.