What is the Steady State Temperature of a Brick Wall in a Fire?

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Homework Statement


A fire in a room rapidly raises the temperature of the surface of the wall to a steady value of 1000°C. on the other side of the wall is a large warehouse, whose ambient air temperature is 20°C. If the wall is solid brick, 200 mm thick, with thermal conductivity of 0.72 W/m°C, what is the steady state temperature of the surface of the wall ( on the warehouse side) in °C. You may assume the heat transfer coeffiecient of the air in the warehouse is 12W/m^2°C


Homework Equations



d^2T/dx^2 =ρc dT/ kdt

The Attempt at a Solution



this is a second order differential equation.

Please help me. thanks in advance!
 
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The equation for heat flow is
dQ/dt = kA(Δ∅)/x
Where dQ/dt = rate of heat flow in Watts (or Watts/m^2)
k = thermal conductivity W/m
A = cross sectional area (1m^2)
(Δ∅)/x = (difference in temp)/thickness
Hope this gets you started
 
technician said:
The equation for heat flow is
dQ/dt = kA(Δ∅)/x
Where dQ/dt = rate of heat flow in Watts (or Watts/m^2)
k = thermal conductivity W/m
A = cross sectional area (1m^2)
(Δ∅)/x = (difference in temp)/thickness
Hope this gets you started

thank you technician :) i use different approarch in solving this problem. I used electrical analogy instead of solving the differentail equation.
 

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