A hot surface at 350°C is to be cooled by attaching straight aluminum rectangular fins (k-250 W/m K) with 35 mm length, 70 mm width and 5 mm base thickness. Fins are exposed to an ambient air condition of 28°C and heat transfer coefficient is 35 W/m² K. If there are 1750 fins per m² surface area, calculate; a. The heat transfer rate from a single fin. b. The increase in the rate of heat transfer per m² surface area as a result of attaching 1750 fins. c. Determine the overall effectiveness of the fins.

A hot surface at 350°C is to be cooled by attaching straight aluminum rectangular fins (k-250 W/m K) with 35 mm length, 70 mm width and 5 mm base thickness. Fins are exposed to an ambient air condition of 28°C and heat transfer coefficient is 35 W/m² K. If there are 1750 fins per m² surface area, calculate; a. The heat transfer rate from a single fin. b. The increase in the rate of heat transfer per m² surface area as a result of attaching 1750 fins. c. Determine the overall effectiveness of the fins.

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 1.18P: The heat transfer coefficient for a gas flowing over a thin float plate 3-m long and 0.3-m wide...

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Conduction and Convection

When energy travels from one object to another it is said to have undergone heat transfer. Heat transfer is nothing but the transfer of thermal energy or internal energy from one thing to another, like e.g., when a vessel with water, kept on top of a burner, heats up because of the flame underneath it.

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