Strangely, this is for a Mat Sci Class. It is probably not as complicated as I am making it out to be, but the book has no suggestions on how to handle this problem.(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

Calculate rate of heat loss through a fireclay refractory wall of wall with thickness .1m. Furnace operates at 1000C and outside is at 100C. Thermal conductivity of the clay at 1000C is 1.5, and 1.1 at 100C

2. Relevant equations

Rate of heat loss per square meter = q = -kdT/dx

dT = 900C

dx = .1m

k(1000) = 1.5

k(100) = 1.1

(q is what I am trying to find)

3. The attempt at a solution

After realizing that there are two thermal conductivity values, so I could not just plug in the numbers...I figured I would assume a linear relationship between K and Temperature, so that k = 1.1 + .4T/900 - 100(.4/900). But I'm not sure if that gets me anywhere as for solving the problem. Or...could I just take the average k value to be (1.1+1.5)/2 and use that? I'm not sure what the appropriate way to go about this problem is...

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# Rate of heat loss with two thermal conductivity values

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