An engineer designing a light aircraft is trying to make an estimate of the radius of the propeller needed. The design speed of the aircraft is 69m/s into still air and at this speed experience allows the engineer to assume a propeller efficiency of 0.8. Other analysis shows that a thrust of 9296N must be supplied by the propeller to maintain the design speed. Assuming a constant air density of 1.21 kg/m3, determine the radius of the ideal propeller in m to 2 decimal places. Note: Use the propulsive efficiency equation to find the final downstream speed of the air and check that this makes physical sense before calculating the radius.

An engineer designing a light aircraft is trying to make an estimate of the radius of the propeller needed. The design speed of the aircraft is 69m/s into still air and at this speed experience allows the engineer to assume a propeller efficiency of 0.8. Other analysis shows that a thrust of 9296N must be supplied by the propeller to maintain the design speed. Assuming a constant air density of 1.21 kg/m3, determine the radius of the ideal propeller in m to 2 decimal places. Note: Use the propulsive efficiency equation to find the final downstream speed of the air and check that this makes physical sense before calculating the radius.

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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