A 30 m long pipe (k = 40 W/m-K) has an outer diameter of 15 cm...

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A 30 m long pipe (k = 40 W/m-K) has an outer diameter of 15 cm and a wall thickness of 0.5 cm. Hot steam at 400°C flows through the pipe and heat is lost to the surrounding air at 30°C. Heat transfer coefficients at inner and outer surfaces of the pipe are 35 W/m² K and 10 W/m²-K, respectively. Assume one-dimensional steady-state conduction and negligible radiation. (a) Determine the rate of heat loss from the steam to the surroundings. (b) To reduce the heat loss to the surroundings, the pipe now is thermally insulated with a thermal insulation (k = 0.05 W/m K) of 5 cm thick. Heat transfer coefficients at outer surfaces of the insulation is also 10 W/m² K. Determine the rate of heat loss from the steam to the surroundings after applying the thermal insulation. Given: Thermal resistance of convection: R = hA In(¹2) Thermal resistance of cylinder: R= 2πLK A 30 m long pipe (k = 40 W/m-K) has an outer diameter of 15 cm and a wall thickness of 0.5 cm. Hot steam at 400°C flows through the pipe and heat is lost to the surrounding air at 30°C. Heat transfer coefficients at inner and outer surfaces of the pipe are 35 W/m² K and 10 W/m²-K, respectively. Assume one-dimensional steady-state conduction and negligible radiation. (a) Determine the rate of heat loss from the steam to the surroundings. (b) To reduce the heat loss to the surroundings, the pipe now is thermally insulated with a thermal insulation (k = 0.05 W/m K) of 5 cm thick. Heat transfer coefficients at outer surfaces of the insulation is also 10 W/m² K. Determine the rate of heat loss from the steam to the surroundings after applying the thermal insulation. Given: Thermal resistance of convection: R = hA In(¹2) Thermal resistance of cylinder: R= 2πLK

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a Pipe inner diameter 15 cm 2 05 cm 14 cm Pipe outer diameter 15 cm Wall thickness 05 cm Length of p... View the full answer