The cylinder of an engine is I m long and has an outside diameter of 6 cm. The outside surface temperature of the cylinder is 200°C when the ambient temperature is 30°C. The film coefficient of heat transfer is 25 W/m K. The cylinder is provided with 12 longitudinal straight fins of 0.1 cm thickness and 3 cm length. The thermal conductivity of cylinder and fin material is 75 W/m K. Assuming that the fins have insulated tip, determine (a) the percentage increase in heat dissipation due to addition of fins, (b) the temperature at the centre of the fin, (c) the fin efficiency and fin effectiveness, and (d) the overall fin effectiveness. EXAMPLE 4.6

The cylinder of an engine is I m long and has an outside diameter of 6 cm. The outside surface temperature of the cylinder is 200°C when the ambient temperature is 30°C. The film coefficient of heat transfer is 25 W/m K. The cylinder is provided with 12 longitudinal straight fins of 0.1 cm thickness and 3 cm length. The thermal conductivity of cylinder and fin material is 75 W/m K. Assuming that the fins have insulated tip, determine (a) the percentage increase in heat dissipation due to addition of fins, (b) the temperature at the centre of the fin, (c) the fin efficiency and fin effectiveness, and (d) the overall fin effectiveness. EXAMPLE 4.6

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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