Repeat Problem 9.40 with the addition of a radiation shield with emissivity , = 0.1. From Problem

Repeat Problem 9.40 with the addition of a radiation shield with emissivity ε, = 0.1. From Problem 9.40: Calculate the equilibrium temperature of a thermocouple in a large air duct if the air temperature is 1367 K, the duct-wall temperature 533 K, the emittance of the couple 0.5, and the convective heat transfer coefficient, hc, is 114 W/(m2 K).GIVENA thermocouple surrounded by a radiation shield in a large air ductAir temperature (Ts) = 1367 KDuct wall temperature (Td) = 533 KThe emissivity of the thermocouple (εtc) = 0.5The convective heat transfer coefficient (hc) = 114 W/(m2 K)Shield emissivity (εs) = 0.1ASSUMPTIONSConduction along the thermocouple is negligibleThe walls of the duct are blackThe CO2 and H2O in the air are negligibleThe heat transfer coefficient on the inside and outside of the shield is hcThe conductive thermal resistance of the shield is negligibleThe view factor between the shield and the thermocouple ?? 1The surface area of the shield is large compared to that of the thermocoupleShield and thermocouple are grayThe thermocouple and shield can be approximated by infinitely long concentric cylindersConvective heat transfer between the shield and thermocouples isnegligible

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Ta- 533 K Alr T.1367 K Thermocouple Te =? Ee-0.5 Shleld, T. -0.1