Thermo- Heated Air in Brick Box.

[zeus77]

Hello!

This is a question purposed to me by my professor as we went over the mathematics behind the diffusion of heat flow through solids.

Many parts of this question are left up to us to create. Here is what i am working with.

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A m^3 box made of Brick .1m thick has air at 30C. Out side is 20C.
What is the temp. inside the box after 1 hour? 12hours? Aprox. How long until the air is 20C inside also?

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This question was assigned when looking at Heat flow equations, these equations are to look at the distribution of heat inside the wall with constant heat sources on either side. Unlike this problem, dispite my best efforts any attempt to change them into a dynamic system fails.

Having thought about this problem here is what i think is my approach, some one care to help?

1) Set volume of air to 1m^3, with 30C and standard preasure. Find the Energy inside the box.(need help here)
2)Using the surface area of the box, the rate of energy/heat transfer from Brick, the energy difference inside/out.

R-valuebrick= 0.80 (k*m^2/W)
R=D/k=.1m/k

3)Need help!


Ok from what i can tell, i should be able to calculate the energy in the box, the rate energy is lost using the brick's R value, and create an formula specific to this situation. Can some one please get me on the right track?

 

[zeus77]

Gah,

Wrong part of forum to post this. I apologize, please move if some one has the power (=

 

[astrokreng]

Hello!

I would approach this problem by first understanding the basic principles of heat transfer and thermodynamics. The key equation for this problem would be the heat transfer equation, which states that the rate of heat transfer is proportional to the temperature difference and the thermal conductivity of the material. In this case, the material is brick and we can use its thermal conductivity to calculate the rate of heat transfer through the walls of the box.

Next, I would consider the initial conditions of the box, with air at 30C and the outside temperature at 20C. From here, we can use the heat transfer equation to calculate the temperature inside the box after 1 hour, 12 hours, and the approximate time it will take for the air inside to reach 20C. This would involve solving a differential equation, which may require some advanced mathematical techniques.

Another approach could be to use a computer simulation to model the heat flow in the box over time. This would allow us to change different variables and see how they affect the temperature inside the box.

Overall, the key is to understand the fundamental principles and use them to create a mathematical or computational model that accurately represents the situation. I hope this helps guide you in the right direction. Good luck!