Question 2: A circuit board houses on its surface 120 closely spaced logic chips, each dissipating 0.12 W, If the heat transfer from the back surface of the board is negligible, calculate (a) the amount of heat this circuit board (15 cm x 20 cm) dissipates during a 10-hour period, in kWh, and (b) the heat flux on the surface of the circuit board, in W/m

Question 2: A circuit board houses on its surface 120 closely spaced logic chips, each dissipating 0.12 W, If the heat transfer from the back surface of the board is negligible, calculate (a) the amount of heat this circuit board (15 cm x 20 cm) dissipates during a 10-hour period, in kWh, and (b) the heat flux on the surface of the circuit board, in W/m

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 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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The heat transfer coefficient between a surface and a liquid is 57 W/(m2K). How many watts per square meter will be transferred in this system if the temperature difference is 10C?
1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the convection heat transfer coefficient between the outer surface of the container and the air is 6.8 , the temperature of the air is 27°C, and the temperature of the surface of the sphere is –183°C, determine the rate of heat transfer by convection.
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A 12-cm × 18-cm circuit board houses on its surface 100 closely spaced logic chips, each dissipating 0.06 W in an environment at 40°C. The heat transfer from the back surface of the board is negligible. If the heat transfer coefficient on the surface of the board is 10 W/m2·K, determine (a) the heat flux on the surface of the circuit board, in W/m2; (b) the surface temperature of the chips; and (c) the thermal resistance between the surface of the circuit board and the cooling medium, in °C/W.
A circuit board houses on its surface 120 closely spaced logic chips, each dissipating 0.12 W. If the heat transfer from the back surface of the board is negligible, calculate (a) the amount of heat this circuit board (15 cm x 20 cm) dissipates during a 10-hour period, in kWh, and (b) the heat flux on the surface of the circuit board, in W/m2.
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Consider a 10 cm wall made of polyurethane board (k = 0.0260 W/m.K) which is exposed to still air (h = 9.37 W/m2.K) on the inside and outer surface exposed to 24 km/h wind (h = 34 W/m2.K). Determine the overall coefficient of heat transfer in W/m2.K.
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