(b) Consider a furnace that is situated in a room withsurrounding air temperature of 30°C and an averageFurnacefrontTsur = 30°Cconvection coefficient of 10 W/m2°C. Convection and2 = 0.1radiation heat transfer occur between the furnace outersurface and the surroundings. The furnace front is madeAir, 30°Ch = 10 W/m2-Kof two parallel plates, where the inner plate has atemperature of 600°C. To ensure safety and preventRadiationshieldsthermal burn on the people working around the furnace,the outer surface temperature of the furnace should bekept below 45°C. Based on the above information,determine the number of radiation shield that should beT= 600°CT<45°Cplaced in parallel in the surface front.Assume all the surfaces have the same emissivity of 0.1 and show different steps ofcalculations with necessary diagrams.

Answered: Image /qna-images/answer/6d9cd170-f339-4d17-ae8b-76271e962c4f.jpg

Answered: the outer surface temperature of the…

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.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.36P

See similar textbooks

Similar questions

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.
An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a resistance of 310-4 ohm per meter of length. If the air around this line is at v, determine the surface temperature on a windy day, assuming a wind blows across the line at 33 km/h.
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.
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?
calculate the convection heat transfer rate over a surface of area 1 m^2 having heat convection coefficient of 40 W/m^2K and temperature difference of 25 °C
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
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.
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.
A plate heated with a heat flux of 5 kW/m^2 and has an emissivity of 0.3. the air is over the plate has a temperature of 313 K and the heat transfer coefficient is 15 W/m^2K. the surrounding temperature is also the same as the air temperature. *Determine the surface temperature of the plate.
A person puts apples, whose initial temperature is 30 °C, into a 2 °C-cold room. If the heattransfer coefficient at the apples’ surface is 8 W/m2K, determine the center and surfacetemperatures of the apples after one hour. Assume the apples are spherical in shape with adiameter of 9 cm and also state your assumptions
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
Define and explain the physical significance of the following:(a)prandtl number(b) Reynolds number (c)Nusselt number In which mode of heat transfer is the convection heat transfer coefficient usually higher, natural convection or force convection?why?

SEE MORE QUESTIONS

Recommended textbooks for you

Principles of Heat Transfer (Activate Learning wi…

Mechanical Engineering

ISBN:

9781305387102

Author:

Kreith, Frank; Manglik, Raj M.

Publisher:

Cengage Learning