B) An engine with an indicated thermal efficiency of 50% and mechanical efficiency of 45% consumes 15kg/h of a fuel at a fixed speed. The brake mean effective pressure is 6.5 bar and the mean piston speed is 13m/s. Assuming it is a four cylinder four- stroke square engine, determine the crank radius and the speed in rpm. Take the heating value of the fuel =42MJ/kg and combustion efficiency 100%.

B) An engine with an indicated thermal efficiency of 50% and mechanical efficiency of 45% consumes 15kg/h of a fuel at a fixed speed. The brake mean effective pressure is 6.5 bar and the mean piston speed is 13m/s. Assuming it is a four cylinder four- stroke square engine, determine the crank radius and the speed in rpm. Take the heating value of the fuel =42MJ/kg and combustion efficiency 100%.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter39: Residential Energy Auditing

Section: Chapter Questions

Problem 4RQ: Performing a home energy audit starts with a visualinspection of a home and its energy systems which...

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