Conductive Heat Transfer through a surface
Conductive Heat Transfer through a surface
(OP)
Ok I have what I believe is a relatively simple calculation but I can't track down my equation and I don't have any textbooks at my disposal.
Working with a ceramic nozzle tip at 1250-1475 deg C which is attached to and Aluminum brace. I need to find the temperature of the ceramic 19-21 cms down the nozzle. I am only looking at it through pure conduction through the ceramic. the thermal conductivity of nozzle is 35 W/mk. Going to measure thickness soon. Can anyone point me in the direction of the equations or laws i need?
Thank You
Thor
Working with a ceramic nozzle tip at 1250-1475 deg C which is attached to and Aluminum brace. I need to find the temperature of the ceramic 19-21 cms down the nozzle. I am only looking at it through pure conduction through the ceramic. the thermal conductivity of nozzle is 35 W/mk. Going to measure thickness soon. Can anyone point me in the direction of the equations or laws i need?
Thank You
Thor





RE: Conductive Heat Transfer through a surface
RE: Conductive Heat Transfer through a surface
Lienhard has a free HT text: http://web.mit.edu/lienhard/www/ahtt.html
TTFN
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RE: Conductive Heat Transfer through a surface
How is the geomety of the nozzle? What is the ambient temperature of the surrounding medium? What is the temperature of the aluminium?
If your geometry is basic you may be lucky and somebody one did some nomogram like stuff or set up some fairly simple differential equation. But i dont recall any just now. I resently saw studies of a choke valve during start whith cold gas and high dP where the aim was to check temperature profile because of an unfortunate flange sealing material. That was pretty advanced stuff (at least to an engineer like me
Best regards
Morten
RE: Conductive Heat Transfer through a surface
Comprehension is not understanding. Understanding is not wisdom. And it is wisdom that gives us the ability to apply what we know, to our real world situations
RE: Conductive Heat Transfer through a surface
RE: Conductive Heat Transfer through a surface
A brute force approach might be to take the ratio of σcer/σal times the temperature delta relative to ambient. The result is the temperature at the interface assuming equal effective physical thermal path lengths. I get about 220°C with that, and the same numbers give a heat flux of about 29 W/cm2
TTFN
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RE: Conductive Heat Transfer through a surface
RE: Conductive Heat Transfer through a surface
He just wants minimum guidance to do it him/herself.
So far he/she hasn't gotten the help needed because of poor clarity of the description.
I would suggest that he/she post a drawing of the system to get the help.
RE: Conductive Heat Transfer through a surface
But, I'm more used to the radiation heat transfer from the welding tip and arc, cooled somewhat by the gas flow around the nozzle and arc (MIG).
RE: Conductive Heat Transfer through a surface