4. A car engine with the dimensions 0.6 m high, 0.50 m-wide, and 0.8-m- long. The bottom surface of the engine 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. k = 0.02735 W/m.°C L = 0.8 m v=1.798×10 m²/s Engine block Pr = 0.7228 Air T: = 80°C ɛ = 0.95 Va = 80 km/h Tx = 20°C

4. A car engine with the dimensions 0.6 m high, 0.50 m-wide, and 0.8-m- long. The bottom surface of the engine 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. k = 0.02735 W/m.°C L = 0.8 m v=1.798×10 m²/s Engine block Pr = 0.7228 Air T: = 80°C ɛ = 0.95 Va = 80 km/h Tx = 20°C

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.31P: A spherical communications satellite, 2 m in diameter, is placed in orbit around the earth. The...

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