(25 pt) A vertical cavity wall of a house has 2.7 m height and 10 m width. The cavity space in the wall has length of 30 cm and involves quiescent air. During a winter day surface of the cavity towards indoors is 15 °C, whereas other surface towards outdoors is 5 °C. a. Calculate the natural convection heat transfer rate across the cavity? b. If the emissivity of the cavity surfaces is 0.7 what is the total heat transfer rate across the cavity? T₁= 15 °C Indoors Cavity Quiescent air L= 30 cm | T₂ = 5 °C H= 2.7 m Width of the wall is 10 m Outdoors

(25 pt) A vertical cavity wall of a house has 2.7 m height and 10 m width. The cavity space in the wall has length of 30 cm and involves quiescent air. During a winter day surface of the cavity towards indoors is 15 °C, whereas other surface towards outdoors is 5 °C. a. Calculate the natural convection heat transfer rate across the cavity? b. If the emissivity of the cavity surfaces is 0.7 what is the total heat transfer rate across the cavity? T₁= 15 °C Indoors Cavity Quiescent air L= 30 cm | T₂ = 5 °C H= 2.7 m Width of the wall is 10 m Outdoors

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.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.45P

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