A concrete block which has dimensions 186x72x250 mm is heated in a furnace at constant 397°C. The density of concrete block is 1600 kg m-3, specific heat capacity is 840 J kg-1 K-1, and thermal conductivity is 0.79 W m-1 K-1. The block is being kept in the furnace for long enough to reach equilibrium. When the equilibrium is reached the block is removed from the furnace and is left to cool in a room with ambient air temperature of 20°C. Assuming that convective heat transfer coefficient is 4.4 W m-2 K-1 calculate Biot number (Bi) to three significant figures.

A concrete block which has dimensions 186x72x250 mm is heated in a furnace at constant 397°C. The density of concrete block is 1600 kg m-3, specific heat capacity is 840 J kg-1 K-1, and thermal conductivity is 0.79 W m-1 K-1. The block is being kept in the furnace for long enough to reach equilibrium. When the equilibrium is reached the block is removed from the furnace and is left to cool in a room with ambient air temperature of 20°C. Assuming that convective heat transfer coefficient is 4.4 W m-2 K-1 calculate Biot number (Bi) to three significant figures.

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 2.55P: 2.55 A long, 1-cm-diameter electric copper cable is embedded in the center of a 25-cm-square...

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