صقات A coat is made of 5 layers of 0.1 mm thick synthetic fabric separated by 1.5 mm thick air space. 1. Calculate the rate of heat loss through the jacket. 2. Compared the heat loss through a jackets without the air space. 3. Calculate the equivalent thickness of a wool coat, which has same total heat resistances of the synthetic fabric. Given: The thermal conductivities are given to be k = 0.13 W/m-°C for synthetic fabric, k = 0.026 W/m-°C for air, and k = 0.035 W/m °C for wool fabric, area of heat transfer 1.1 m², T1 = 28 °C, To=(-5 °C), and air heat transfer coefficient 25 W/m². C.) Assumptions: المة المرتلة من الخارج مرو المنوال 1 Heat transfer is steady since there is no indication of change with time. 2 Heat transfer through the jacket is one-dimensional. 3 Thermal conductivities are constant. 4 Heat transfer coefficients account for the radiation heat transfer.

صقات A coat is made of 5 layers of 0.1 mm thick synthetic fabric separated by 1.5 mm thick air space. 1. Calculate the rate of heat loss through the jacket. 2. Compared the heat loss through a jackets without the air space. 3. Calculate the equivalent thickness of a wool coat, which has same total heat resistances of the synthetic fabric. Given: The thermal conductivities are given to be k = 0.13 W/m-°C for synthetic fabric, k = 0.026 W/m-°C for air, and k = 0.035 W/m °C for wool fabric, area of heat transfer 1.1 m², T1 = 28 °C, To=(-5 °C), and air heat transfer coefficient 25 W/m². C.) Assumptions: المة المرتلة من الخارج مرو المنوال 1 Heat transfer is steady since there is no indication of change with time. 2 Heat transfer through the jacket is one-dimensional. 3 Thermal conductivities are constant. 4 Heat transfer coefficients account for the radiation heat transfer.

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.

Chapter2: Steady Heat Conduction

Section: Chapter Questions

Problem 2.59P

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