One side (the hot side facing the room) of the radiator plate is maintained at a temperature of 80°C, the other sides are assumed to be insulated, as shown in Figure 1. If the following assumptions can be made: 1) steady operating conditions exist; 2) the air is an ideal gas; 3) the local" atmospheric pressure is 1.00 atm: (a) Briefly and qualitatively analyze the four different locations for the radiators marked A), B), C) and D), as shown in Figure 1, and rank them in terms of heat transfer efficiency by natural convection. (b) Determine the rate of heat transfer from the radiator plate by natural convection if the plate is A) vertical and C) horizontal with the hot surface facing down. Compare the two and provide a brief discussion of the findings. Nu-0.59Ral Nu-0.1 Ra 0.387Ral Nu- - {0.825 + 11 + (0.492/Pr) 14:27) (complex but more accurate) Use vertical plate equations for the upper surface of a cold plate and the lower surface of a hot plate Replace g by g cose Nu-0.54Ra Nu-0.15Ra Nu-0.27Ra for Ra < 10º

One side (the hot side facing the room) of the radiator plate is maintained at a temperature of 80°C, the other sides are assumed to be insulated, as shown in Figure 1. If the following assumptions can be made: 1) steady operating conditions exist; 2) the air is an ideal gas; 3) the local" atmospheric pressure is 1.00 atm: (a) Briefly and qualitatively analyze the four different locations for the radiators marked A), B), C) and D), as shown in Figure 1, and rank them in terms of heat transfer efficiency by natural convection. (b) Determine the rate of heat transfer from the radiator plate by natural convection if the plate is A) vertical and C) horizontal with the hot surface facing down. Compare the two and provide a brief discussion of the findings. Nu-0.59Ral Nu-0.1 Ra 0.387Ral Nu- - {0.825 + 11 + (0.492/Pr) 14:27) (complex but more accurate) Use vertical plate equations for the upper surface of a cold plate and the lower surface of a hot plate Replace g by g cose Nu-0.54Ra Nu-0.15Ra Nu-0.27Ra for Ra < 10º

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.3P: 2.3 The shield of a nuclear reactor is idealized by a large 25-cm-thick flat plate having a thermal...

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1.76 Explain a fundamental characteristic that differentiates conduction from convection and radiation.
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Two parallel discs pf 1m diameter are situated 2m part in surroundings at a temparature 20 C. The inner side of one disc has an emissivity of 0.5 and is manintained at 500 C by electric resistance heating and the outer side of the disc is well insulated. The other disc is Two parallel discs of 1m diameter are situated 2m apart in surroundings at a temperature of 20 oC. The inner side of one disc has an emissivity of 0.5 and is maintained at 500 oC by electric resistance heating and the outer side of the disc is well insulated. The other disc is open to radiation on both sides and reaches an equilibrium temperature. Calculate this equilibrium temperature and the heat flow rate from the first disc, assuming heat transfer is entirely by radiation.
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