A 2m diameter disk made of brick fire 30cm thick is in contact with a 3m x 2m insulating brick wall that is 3cm thick. determine the temperature between the surfaces of wood and insulating wall and the time (in seconds) it would take to generate 20 Watts. The temperature on the free sides of the wood and insulating brick is 60°C and 50°C respectively. The thermal conductivity of the wood is 0.47 W/m-K and 0.15 W/m-K for the insulating brick wall. DETERMINE: A) The temperature (in degrees Celsius) between the surfaces B) Time (in seconds) it would take to generate 20 Watts

A 2m diameter disk made of brick fire 30cm thick is in contact with a 3m x 2m insulating brick wall that is 3cm thick. determine the temperature between the surfaces of wood and insulating wall and the time (in seconds) it would take to generate 20 Watts. The temperature on the free sides of the wood and insulating brick is 60°C and 50°C respectively. The thermal conductivity of the wood is 0.47 W/m-K and 0.15 W/m-K for the insulating brick wall. DETERMINE: A) The temperature (in degrees Celsius) between the surfaces B) Time (in seconds) it would take to generate 20 Watts

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 1.10P: 1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss...

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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.
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
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1.60 Two electric resistance heaters with a 20 cm length and a 2 cm diameter are inserted into a well-insulated 40-L tank of water that is initially at 300 K. If each heater dissipates 500 W, what is the time required for bringing the water temperature in the tank to 340 K? State your assumption for your analysis.
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1.10 A heat flux meter at the outer (cold) wall of a concrete building indicates that the heat loss through a wall of 10-cm thickness is . If a thermocouple at the inner surface of the wall indicates a temperature of 22°C while another at the outer surface shows 6°C, calculate the thermal conductivity of the concrete and compare your result with the value in Appendix 2, Table 11.
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