A steel ball of density 7800 kg/m³ and specific heat 0.47 kJ/kg-K having 10 cm diameter at 300°C is placed in atmosphere at 30°C. Calculate the initial rate of cooling in °C/sec. Assume convective heat transfer coefficient h = 15W / (m ^ 2) - K. Neglect heat loss by radiation.

A steel ball of density 7800 kg/m³ and specific heat 0.47 kJ/kg-K having 10 cm diameter at 300°C is placed in atmosphere at 30°C. Calculate the initial rate of cooling in °C/sec. Assume convective heat transfer coefficient h = 15W / (m ^ 2) - K. Neglect heat loss by radiation.

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 8.3P

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Question

A steel ball of density 7800 kg/m³ and specific
heat 0.47 kJ/kg-K having 10 cm diameter at
300°C is placed in atmosphere at 30°C. Calculate
the initial rate of cooling in °C/sec. Assume
convective heat transfer coefficient h = 15W / (m
^ 2) - K . Neglect heat loss by radiation.

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