The average thermal conductivity of the walls (including windows) and roof of a house in the figure shown below is 4.8 10-4 kW/m · °C, and their average thickness is 21.6 cm. The house is heated with natural gas, with a heat of combustion (energy given off per cubic meter of gas burned) of 9,300 kcal/m3. How many cubic meters of gas must be burned each day to maintain an inside temperature of 27.4°C if the outside temperature is 0.0°C? Disregard surface air layers, radiation, and energy loss by heat through the ground. m3

The average thermal conductivity of the walls (including windows) and roof of a house in the figure shown below is 4.8 10-4 kW/m · °C, and their average thickness is 21.6 cm. The house is heated with natural gas, with a heat of combustion (energy given off per cubic meter of gas burned) of 9,300 kcal/m3. How many cubic meters of gas must be burned each day to maintain an inside temperature of 27.4°C if the outside temperature is 0.0°C? Disregard surface air layers, radiation, and energy loss by heat through the ground. m3

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 1.78P: What are the important modes of heat transfer for a person sitting quietly in a room? What if the...

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