Example A thin rod has length 1 m and cross-section 1 cm x 1 cm. The left-hand end is kept at 100 C, whilst the right-hand end is insulated. T = 20°C T=100°C The heat flux across any section of area A is Rod given by dT - kA dr x = 0 s= -c(T-T.) where the conductivity k= 1000 W m ' K-!. The rod is allowed to cool along its length at a rate proportional to its difference from the ambient temperature (Newton's law of cooling); i.e. the heat source per unit length is: s=-c(T-T) where the ambient temperature T. = 20 °C and the coefficientc=25 W m K-1

Example A thin rod has length 1 m and cross-section 1 cm x 1 cm. The left-hand end is kept at 100 C, whilst the right-hand end is insulated. T = 20°C T=100°C The heat flux across any section of area A is Rod given by dT - kA dr x = 0 s= -c(T-T.) where the conductivity k= 1000 W m ' K-!. The rod is allowed to cool along its length at a rate proportional to its difference from the ambient temperature (Newton's law of cooling); i.e. the heat source per unit length is: s=-c(T-T) where the ambient temperature T. = 20 °C and the coefficientc=25 W m K-1

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 2.47P

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