A long pipe carrying hot water loses heat to the ambient air. The heat loss was measured to be 480 W/m² at the outer surface of the pipe. The temperature of the hot water and the ambient air are 60°C and 20°C, respectively. The pipe has an inner diameter of 8 cm and outer diameter of 12 cm. The thermal conductivity of the pipe material is 1.4 W/m.K. If the convection coefficient of the hot water inside the pipe is 80 W/m².K, what is the convection coefficient of the ambient air? Assume steady and one-dimensional heat transfer. Neglect radiation.

A long pipe carrying hot water loses heat to the ambient air. The heat loss was measured to be 480 W/m² at the outer surface of the pipe. The temperature of the hot water and the ambient air are 60°C and 20°C, respectively. The pipe has an inner diameter of 8 cm and outer diameter of 12 cm. The thermal conductivity of the pipe material is 1.4 W/m.K. If the convection coefficient of the hot water inside the pipe is 80 W/m².K, what is the convection coefficient of the ambient air? Assume steady and one-dimensional heat transfer. Neglect 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.

Chapter1: Basic Modes Of Heat Transfer

Section: Chapter Questions

Problem 1.9P: Heat is transferred at a rate of 0.1 kW through glass wool insulation (density=100kg/m3) with a 5-cm...

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