An uninsulated steam pipe of 100-mm diameter is routed through a building whose walls and air are at 27°C. Pressurized steam maintains a pipe surface temperature of 147°C, and the coefficient associated with natural convection is h =10 W/m2.K. The surface emissivity is ɛ= 0.8. What is the rate of heat loss per unit length from the steam line?

An uninsulated steam pipe of 100-mm diameter is routed through a building whose walls and air are at 27°C. Pressurized steam maintains a pipe surface temperature of 147°C, and the coefficient associated with natural convection is h =10 W/m2.K. The surface emissivity is ɛ= 0.8. What is the rate of heat loss per unit length from the steam line?

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.8P

See similar textbooks

Similar questions

Determine the rate of heat loss from the wall of a building resulting from a 16 km/h wind blowing parallel to its surface. The wall is 24 m long and 6 m high, its surface temperature is 27C, and the temperature of the ambient air is 4C.
5.7 The average Reynolds number for air passing in turbulent flow over a 2-m-long, flat plate is . Under these conditions, the average Nusselt number was found to be equal to 4150. Determine the average heat transfer coefficient for an oil having thermal properties similar to those in Appendix 2, Table 18, at at the same Reynolds number and flowing over the same plate.
3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the atmosphere from outer space. If its original temperature is 38°C, the effective average temperature of the atmosphere is 1093°C, and the effective heat transfer coefficient is , estimate the temperature of the shell after reentry, assuming the time of reentry is 10 min and the interior of the shell is evacuated.
The heat transfer coefficient for a gas flowing over a thin float plate 3-m long and 0.3-m wide varies with distance from the leading edge according to hc(x)=10x1/4Wm2K If the plate temperature is 170C and the gas temperature is 30C, calculate (a) the average heat transfer coefficient, (b) the rate of heat transfer between the plate and the gas, and (c) the local heat flux 2 m from the leading edge. Problem 1.18
The air-conditioning system in a Chevrolet van for use in desert climates is to be sized. The system is to maintain an interior temperature of 20C when the van travels at 100 km/h through dry air at 30C at night. If the top of the van is idealized as a flat plate 6 m long and 2 m wide and the sides as flat plates 3 m tall and 6 m long, estimate the rate at which heat must be removed from the interior to maintain the specified
A 5.0-cm-diameter cylinder is heated to a temperature of 200°C, and air at 30 °C forced across it at a velocity of 50 m/s (h = 180 W/m2 K). If the surface emissivity is 0.7, calculate the total heat loss per unit length if the walls of the enclosing room are at 10 °C. Comment on your calculation.
Air at 25 ° C blows over the hot steel plate whose surface temperature is maintained at 150 ° C. The plates are 50 cm x 40 cm in dimensions and 3 cm thick. The convection heat transfer coefficient on the upper surface is 30 W / (m² ° C). The thermal conductivity of steel is 45 W / (m ° C). Calculate the hourly heat loss from the plate surface. a. heat loss per hour = AnswerkJ. b. If the reverse side surface temperature is maintained, determine the hourly heat loss occurring = AnswerkJ.
Air at 25 ° C blows over the hot steel plate whose surface temperature is maintained at 150 ° C. The plates are 50 cm x 40 cm in dimensions and 2.5 cm thick. The convection heat transfer coefficient on the upper surface is 40 W / (m² ° C). The thermal conductivity of steel is 45 W / (m ° C). Calculate the hourly heat loss from the plate surface. a. heat loss per hour = Answer kJ. b. If the reverse side surface temperature is maintained, determine the hourly heat loss occurring = Answer kJ. Air at 25 ° C blows over the hot steel plate whose surface temperature is maintained at 150 ° C. The plates are 50 cm x 40 cm in dimensions and 2.5 cm thick. The convection heat transfer coefficient on the upper surface is 40 W / (m² ° C). The thermal conductivity of steel is 45 W / (m ° C). Calculate the hourly heat loss from the plate surface. a. heat loss per hour = Answer kJ. b. If the reverse side surface temperature is maintained, determine the hourly heat loss occurring = Answer kJ.