Problem 3The air above the surface of a freshwater lake is at temperature TAwhile the water is at its freezing point T,(T,< T,). After a time telapsed, ice of thickness y has formed. Ássuming that the heat,which is liberated when the water freezes, flows through the ice byconduction and then into the air by natural convection, proveyT, – T,plh 2Kwhere h is the convection coefficient per unit area and is assumedconstant while ice forms, K is the thermal conductivity of ice, I is thelatent heat of fusion of ice, and p is the density of ice (Hint: thetemperature of the upper surface is variable. Ássume that the icehas a thickness y and imagine an infinitesimal thickness dy to formin time dt.)

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The air above the surface of a freshwater lake is at temperature TA while the water is at its freezing point T,(T,< T). After a time t elapsed, ice of thickness y has formed. Ássuming that the heat, which is liberated when the water freezes, flows through the ice by conduction and then into the air by natural convection, prove y y² T, – T, h 2K pl where h is the convection coefficient per unit area and is assumed constant while ice forms, K is the thermal conductivity of ice, / is the latent heat of fusion of ice, and p is the density of ice (Hint: the temperature of the upper surface is variable. Assume that the ice has a thickness y and imagine an infinitesimal thickness dy to form in time dt.)

The air above the surface of a freshwater lake is at temperature TA while the water is at its freezing point T,(T,< T). After a time t elapsed, ice of thickness y has formed. Ássuming that the heat, which is liberated when the water freezes, flows through the ice by conduction and then into the air by natural convection, prove y y² T, – T, h 2K pl where h is the convection coefficient per unit area and is assumed constant while ice forms, K is the thermal conductivity of ice, / is the latent heat of fusion of ice, and p is the density of ice (Hint: the temperature of the upper surface is variable. Assume that the ice has a thickness y and imagine an infinitesimal thickness dy to form in time dt.)

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.

Chapter3: Transient Heat Conduction

Section: Chapter Questions

Problem 3.10P: 3.10 A spherical shell satellite (3-m-OD, 1.25-cm-thick stainless steel walls) re-enters the...

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