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The temperature distribution at a certain time instant through a 50 cm thick wall is prescribed by the relation T = 300 – 500 x – 100 x2 + 140 x3 Where temperature t is in degree Celsius and the distance x in meters has been measured from the hot surface. If thermal conductivity of the wall material is 20 k J/m hr degree, calculate the heat energy stored per unit area of the wall

The temperature distribution at a certain time instant through a 50 cm thick wall is prescribed by the relation T = 300 – 500 x – 100 x2 + 140 x3 Where temperature t is in degree Celsius and the distance x in meters has been measured from the hot surface. If thermal conductivity of the wall material is 20 k J/m hr degree, calculate the heat energy stored per unit area of the wall Correct Answer 4100 k J/hr

d t/d x = -500 + 200 x + 420 x2. Now heat storage rate = Q IN – Q OUT = 10000 – 5900 = 4100 k J/hr.

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