A spherical ball with a diameter of 5 cm is suspended in the middle of a room with a temperature of 20°C. The temperature of the ball is 70°C. The heat transfer coefficient of the ball is 15 W/(m2.°C) and the emissivity of the ball surface is 0.8. What is the total heat transfer rate from the ball to the air assuming both temperatures are constant? Heat conduction through the suspension system can be neglected.

A spherical ball with a diameter of 5 cm is suspended in the middle of a room with a temperature of 20°C. The temperature of the ball is 70°C. The heat transfer coefficient of the ball is 15 W/(m2.°C) and the emissivity of the ball surface is 0.8. What is the total heat transfer rate from the ball to the air assuming both temperatures are constant? Heat conduction through the suspension system can be neglected.

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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.19P: 1.19 A cryogenic fluid is stored in a 0.3-m-diameter spherical container is still air. If the...

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SOLVE STEP BY STEO IN DIGITAL FORMAT A 9-cm-diameter sphere, whose surface is maintained at a temperature of 110°C, is hanging in the center of a room at 20°C. If the convective heat transfer coefficient is 15 W/m²"C, and the emissivity of the surface is 0.8, calculate the total rate of heat transfer from the sphere. Air 20°C D=9 cm 110°C