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Re: Please clarify Thermal question
Dear Jagadeesh,
If you dont mind, will like to ask you, why you want to make an analysis, cause it can be done through a simple calculations as below
q = ε σ (Th4 - Tc4)A
where
q = heat transfer per unit time (W)
ε = emissivity of the object (one for a black body)
σ = 5.6703 10-8 (W/m2K4) - The Stefan-Boltzmann Constant
Th = hot body absolute temperature (K)
Tc = cold surroundings absolute temperature (K)
A = area exposed to environment of the emitting body (m2)
Just multiply above retrived q by 4 (as the body is kept for 4 seconds in environment), you will get total heat loss to environment.
i.e.
Loss to environment = Heat transfer per unit time X Time
Once you recieve total loss to environment, again divide it with specific heat of body
i.e. Temperature drop (or Temperature difference) = Heat loss / Specific Heat of body
So ultimate temperature of body will be equal to 560 - Temperature Drop.
Hope this will help you.
Thanks
Sandip Darveshi.
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Re: Please clarify Thermal question
this assumes the heat loss is only from radiation. what about convection. but i agree, you could solve this problem by hand.
with the software, you're looking at a transient thermal analysis in simulation professional.
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Re: Please clarify Thermal question
Yes Jared you are right, I will like to correct myself.
Total Heat Loss = Heat Loss due to Convection + Heat Loss due to Radiation.
Convection q (conv) = hA(Th - Tc)
where
q(conv) = heat transfer per unit time due to Convection (W)
h = heat transfer coeficient (W/m2K)
Th = hot body absolute temperature (K)
Tc = cold surroundings absolute temperature (K)
A = area exposed to environment of the emitting body (m2)
__________________
Radiation q (rad) = ε σ (Th4 - Tc4)A
where
q(rad) = heat transfer due to Radiation per unit time (W)
ε = emissivity of the object (one for a black body)
σ = 5.6703 10-8 (W/m2K4) - The Stefan-Boltzmann Constant
_________________
Total Heat Loss = q(conv) + q(rad)
Just multiply above retrived Total Heat Transfer by 4 (as the body is kept for 4 seconds in environment), you will get total heat loss to environment.
i.e.
Loss to environment = Heat transfer per unit time X Time
Divide Total Heat Loss to Environment with specific heat of body
i.e. Temperature drop (or Temperature difference) = Heat loss / Specific Heat of body
So ultimate temperature of body will be equal to 560 - Temperature Drop.
Thanks
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Re: Please clarify Thermal question
Jagadeesh,
In addition to what Sandip and Jared said, the body will not have a single temperature. The skin will be cooler than the interior.
Jerry S.