Water is heated by submerging 50 mm-diameter, thin-walled copper tubes in a tank and passing hot combustion gases (Tg=750 K) through the tubes. To enhance heat transfer to the water, four straight fins of uniform cross section, which form a cross, are inserted in each tube. The fins are 5 mm thick and are also made of copper (k = 400 W/m K). If the tube surface temperature is T = 350 K and the mass flow rate of gas = 1.1 kg/s. What is the overall efficiency of the fins? Treat gas as air. D-50 mn -T,- 350 K Wabr -Fins (-5 mm) Gases Tube wall

Water is heated by submerging 50 mm-diameter, thin-walled copper tubes in a tank and passing hot combustion gases (Tg=750 K) through the tubes. To enhance heat transfer to the water, four straight fins of uniform cross section, which form a cross, are inserted in each tube. The fins are 5 mm thick and are also made of copper (k = 400 W/m K). If the tube surface temperature is T = 350 K and the mass flow rate of gas = 1.1 kg/s. What is the overall efficiency of the fins? Treat gas as air. D-50 mn -T,- 350 K Wabr -Fins (-5 mm) Gases Tube wall

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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