2) Urethane (k = 0.026 W/m-K) is used to insulate the sidewall and the top and bottom of a cylindrical hot water tank. The insulation is 40 mm thick and is sandwiched between sheet metal of thin-wall construction. The height and inside diameter of the tank are 2 m and 0.8 m, respectively. The tank is in ambient air with T = 10 °C and h = 10 W/m²-K. If the hot water maintains the inner surface at 55 °C, and energy costs amount to $0.15 per kWh, what is the daily cost to maintain the water in storage? Argue that the thermal resistance of the tank wall is negligible. What does this say about the temperature drop across the tank wall?

2) Urethane (k = 0.026 W/m-K) is used to insulate the sidewall and the top and bottom of a cylindrical hot water tank. The insulation is 40 mm thick and is sandwiched between sheet metal of thin-wall construction. The height and inside diameter of the tank are 2 m and 0.8 m, respectively. The tank is in ambient air with T = 10 °C and h = 10 W/m²-K. If the hot water maintains the inner surface at 55 °C, and energy costs amount to $0.15 per kWh, what is the daily cost to maintain the water in storage? Argue that the thermal resistance of the tank wall is negligible. What does this say about the temperature drop across the tank wall?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.22P

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