Q1: Consider a hot automotive engine, which can be approximated as 0.40m wide, and 0.8m long rectangular block. The bottom surface of the block is at a temperature of 80°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. k=0.02735 W/m.°C v=1.798×10° m³/s Air properties at Tf= 50 °C: Pr=0.7228 Answer: Qcom = 1363 W, Qrad = 132 W, Quotal= 1495 W %3D

Q1: Consider a hot automotive engine, which can be approximated as 0.40m wide, and 0.8m long rectangular block. The bottom surface of the block is at a temperature of 80°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. k=0.02735 W/m.°C v=1.798×10° m³/s Air properties at Tf= 50 °C: Pr=0.7228 Answer: Qcom = 1363 W, Qrad = 132 W, Quotal= 1495 W %3D

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

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