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

8th Edition

ISBN: 9781305387102

Author: Kreith, Frank; Manglik, Raj M.

Publisher: Cengage Learning

*expand_more*

*expand_more*

*format_list_bulleted*

Question

Expert Solution

Trending nowThis is a popular solution!

Step by stepSolved in 7 steps with 6 images

Knowledge Booster

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.

*arrow_forward*

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

*arrow_forward*

A spherical communications satellite, 2 m in diameter, is placed in orbit around the earth. The satellite generates 1000 W of internal power from a small nuclear generator. If the surface of the satellite has an emittance of 0.3, and is shaded from solar radiation by the earth, estimate its surface temperature.

*arrow_forward*

A horizontal, 3-mm-thick flat-copper plate, 1-m long and 0.5-m wide, is exposed in air at 27C to radiation from the sun. If the total rate of solar radiation absorbed is 300 W and the combined radiation and convection heat transfer coefficients on the upper and lower surfaces are 20 and 15W/m2K, respectively, determine the equilibrium temperature of the plate.

*arrow_forward*

Consider a hot automotive engine, which can be approximated as a 0.5-m-high, 0.40-m-wide, and 0.8-m-long rectangular block. The bottom surface of the block is at a temperature of 100°C and has an emissivity of 0.95. The ambient air is at 20°C, and the road surface is at 25°C. Determine the rate of heat transfer from the bottom surface of the engine block by convection and radiation as the car travels at a velocity of 80 km/h. Assume the flow to be turbulent over the entire surface because of the constant agitation of the engine block.

*arrow_forward*

Consider a 1.2-m-high and 2-m-wide glass windowwith a thickness of 6 mm, thermal conductivity k = 0.78W/m·K, and emissivity « = 0.9. The room and the wallsthat face the window are maintained at 25°C, and the averagetemperature of the inner surface of the window is measuredto be 5°C. If the temperature of the outdoors is 25°C,determine (a) the convection heat transfer coefficient on theinner surface of the window, (b) the rate of total heat transferthrough the window, and (c) the combined natural convectionand radiation heat transfer coefficient on the outer surface ofthe window. Is it reasonable to neglect the thermal resistanceof the glass in this case?

*arrow_forward*

Q6: A large vertical plate 6.1 m high and 1.22 m wide is maintained at s constant temperature of 57:C and exposed to atmospheric air at 4-C. Caleulate the heat lost by the plate. Answers: Q

*arrow_forward*

An automotive engine can be approximated asa 0.4-m-high, 0.60-m-wide, and 0.7-m-long rectangularblock. The bottom surface of the block is at a temperatureof 75°C and has an emissivity of 0.92. The ambient airis at 5°C, and the road surface is at 10°C. Determine therate of heat transfer from the bottom surface of the engineblock by convection and radiation as the car travels at avelocity of 60 km/h. Assume the flow to be turbulent over theentire surface because of the constant agitation of the engineblock. How will the heat transfer be affected when a 2-mmthickgunk (k = 3 W/m?K) has formed at the bottom surface asa result of the dirt and oil collected at that surface over time?Assume the metal temperature under the gunk still to be 75°C.

*arrow_forward*

The Biot number during a heat transfer process between a sphere and its surroundings is determined to be 0.02. Would you use lumped system analysis or the transient temperature charts when determining the midpoint temperature of the sphere? Why?

*arrow_forward*

In a new residential project, you strongly believethat double-paned windows are ‘better’ than singlepaned windows. Compare the rate of heat loss betweensingle and double-paned windows (1.5 m x 1 m) if thethickness of each pane is (th = 0.4 cm) and (k = 0.9W/m.K). The indoor and outdoor temperatures are 18°C and 2 °C, respectively. Thickness of the air gapbetween the double-paned windows is (th = 1 cm), and(k = 0.022 W/m.K). Image credit: Windowwhirl

*arrow_forward*

Define the cooling of a boiled egg by forced and natural convection.

*arrow_forward*

A 10-m-long section of a 6-cm-diameter horizontal hot-water pipe passes through a large room whose temperature is 27°C. If the temperature and the emissivity of the outer surface of the pipe are 73°C and 0.8, respectively, determine the rate of heat loss from the pipe by (a) natural convection and (b) radiation.

*arrow_forward*

*arrow_back_ios*

- SEE MORE QUESTIONS

*arrow_forward_ios*

Recommended textbooks for you

Principles of Heat Transfer (Activate Learning wi...

Mechanical Engineering

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Cengage Learning

Principles of Heat Transfer (Activate Learning wi...

Mechanical Engineering

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Cengage Learning