Must solve all questions. In order to quench a stainless steel AISI 304 ball of 1 cm diameter (p = 7900 kg'm', = 477J/kg K, and k = 14.9 Wm-K), the ball is heated to a uniform temperature of 1000°C andsubmerged in an oil bath where the temperature of the oil is maintained at 27°C (h = 1192Wm-K).(a) How long does it take for the surface of the ball to reach a temperature of 300°C?(b) What is the center temperature of the ball at that time?(c) If 10,000 balls are to be quenched in one day, calculate the amount of heat (watt) to beremoved from the oil bath to maintain the temperature of the oil at 27°C.

Answered: Image /qna-images/answer/ef4e0142-5586-4440-80f2-ebd42b65222d.jpg

In order to quench a stainless steel AISI 304 ball of 1 cm diameter (p= 7900 kg m', c, = 477 J/kg K, and k = 14.9 Wm K), the ball is heated to a uniform temperature of 1000°C and submerged in an oil bath where the temperature of the oil is maintained at 27°C (h = 1192 Wm K). %3D (a) How long does it take for the surface of the ball to reach a temperature of 300°C? (b) What is the center temperature of the ball at that time? (c) If 10,000 balls are to be quenched in one day, calculate the amount of heat (watt) to be removed from the oil bath to maintain the temperature of the oil at 27C.

In order to quench a stainless steel AISI 304 ball of 1 cm diameter (p= 7900 kg m', c, = 477 J/kg K, and k = 14.9 Wm K), the ball is heated to a uniform temperature of 1000°C and submerged in an oil bath where the temperature of the oil is maintained at 27°C (h = 1192 Wm K). %3D (a) How long does it take for the surface of the ball to reach a temperature of 300°C? (b) What is the center temperature of the ball at that time? (c) If 10,000 balls are to be quenched in one day, calculate the amount of heat (watt) to be removed from the oil bath to maintain the temperature of the oil at 27C.

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.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.4P

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