Question

(a) Discuss with relevant application of a Thermoelectric Device in Cooling Mode. (b) When an inner surface of a 0.5 m thick brick wall of a furnace is at 900

°C, the outer wall was found to be at 150 °C. Calculate the thermal conductivity of the wall if heat loss by conduction per unit area is 3000 Wm2. (c) When an insulated brick wall of 0.45 m thickness and thermal conductivity of 0.68 W/mK is added to the outer surface of the wall from (b), the outer temperature is found to be 80 °C.Calculate the new heat loss by conduction per unit area of the wall and the intermediate temperature between the two types of brick.[60%]

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