Q3: Consider a (15cm x 20cm) printed circuit board (PCB) that has electronic components on one side as shown in the figure. The board is placed in a room at 20°C. The heat loss from the back surface of the board is negligible. The surface temperature of circuit board is 46°C. Determine the total heat loss by convection and radiation if the board is vertical, Take the emissivity of the surface of the board to be 0.8 and assume the surrounding surfaces to be at the same temperature as the air in the room. (Answers: 8W) Hint: The properties of the air at latm. are as follow: k = 0.02607 W/m.°C v = 1.631×10s m²/s Pr = 0.7275 Insulation „PCB, T, 8 W L= 0.2 m Air T,= 20°C

Q3: Consider a (15cm x 20cm) printed circuit board (PCB) that has electronic components on one side as shown in the figure. The board is placed in a room at 20°C. The heat loss from the back surface of the board is negligible. The surface temperature of circuit board is 46°C. Determine the total heat loss by convection and radiation if the board is vertical, Take the emissivity of the surface of the board to be 0.8 and assume the surrounding surfaces to be at the same temperature as the air in the room. (Answers: 8W) Hint: The properties of the air at latm. are as follow: k = 0.02607 W/m.°C v = 1.631×10s m²/s Pr = 0.7275 Insulation „PCB, T, 8 W L= 0.2 m Air T,= 20°C

Name: Q3: Consider a (15cm x 20cm) printed circuit board (PCB) that has ele
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Description: Q3: Consider a (15cm x 20cm) printed circuit board (PCB) that has electronic components onone side as shown in the figure. The board is placed in a room at 20°C. The heat loss from theback surface of the board is negligible. The surface temperature

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 2.53P: Determine the rate of heat transfer per meter length from a 5-cm-OD pipe at 150C placed...

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