A 50-cm-dometer spherical tank is fine, with iced water at 0°C The tank is thin-shelled and Rs temperature can be taken to be the same as the ice temperature The tank is exposed to ambient art at 20°C wrth a heat transfer coefficient of 12 W/m2 K The tank is to be covered wrth glass wool insulation (k = 0 05 W/m K) to decrease the heat gain to the iced water by 90 percent. The required thickness of the insulat

A 50-cm-dometer spherical tank is fine, with iced water at 0°C The tank is thin-shelled and Rs temperature can be taken to be the same as the ice temperature The tank is exposed to ambient art at 20°C wrth a heat transfer coefficient of 12 W/m2 K The tank is to be covered wrth glass wool insulation (k = 0 05 W/m K) to decrease the heat gain to the iced water by 90 percent. The required thickness of the insulat

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 1.45P: An electronic device that internally generates 600 mW of heat has a maximum permissible operating...

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Determine the rate of heat transfer per meter length from a 5-cm-OD pipe at 150C placed eccentrically within a larger cylinder of 85 magnesia wool as shown in the sketch. The outside diameter of the larger cylinder is 15 cm and the surface temperature is 50C.
1.1 On a cold winter day, the outer surface of a 0.2-m-thick concrete wall of a warehouse is exposed to temperature of –5°C, while the inner surface is kept at 20°C. The thermal conductivity of the concrete is 1.2 W/m K. Determine the heat loss through the wall, which is 10-m long and 3-m high. Problem 1.1
3.16 A large, 2.54-cm.-thick copper plate is placed between two air streams. The heat transfer coefficient on one side is and on the other side is . If the temperature of both streams is suddenly changed from 38°C to 93°C, determine how long it takes for the copper plate to reach a temperature of 82°C.
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The heat transfer rate from hot air by convection at 100C flowing over one side of a flat plate with dimensions 0.1m0.5m is determined to be 125 W when the surface of the plate is kept at 30C. What is the average convection heat transfer coefficient between the plate and the air?
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Required information A 14-cm * 20-cm circuit board houses on its surface 100 closely spaced logic chips, each dissipating 0.06 W in the 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. Determirye the thermal resistance between the surface of the circuit board and the cooling medium in terms of °C/W. (Round the final answer to two decimal places.)
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