Example 26.11 An aircraft engine is fitted with a single-sided centrifugal compressor. The aircraft flies with a speed of 900 km/h at an altitude, where the pressure is 0.23 bar and temperature is 217 K. The inlet duct of the impeller eye contains fixed vanes, which gives the air prewhirl of 25° at all radii. The inner and outer diameter of the eye are 180 and 330 mm, respectively. The diameter of the impeller tip is 540 mm and rotational speed is 15000 rpm. Estimate the stagnation pressure at compressor outlet when the mass flow rate is 210 kg/minute. Neglect losses in inlet duct and fixed vanes, and assume that the isentropic efficiency of the compressor is 80%. Take slip factor as 0.9 and power input factor as 1.04.

Example 26.11 An aircraft engine is fitted with a single-sided centrifugal compressor. The aircraft flies with a speed of 900 km/h at an altitude, where the pressure is 0.23 bar and temperature is 217 K. The inlet duct of the impeller eye contains fixed vanes, which gives the air prewhirl of 25° at all radii. The inner and outer diameter of the eye are 180 and 330 mm, respectively. The diameter of the impeller tip is 540 mm and rotational speed is 15000 rpm. Estimate the stagnation pressure at compressor outlet when the mass flow rate is 210 kg/minute. Neglect losses in inlet duct and fixed vanes, and assume that the isentropic efficiency of the compressor is 80%. Take slip factor as 0.9 and power input factor as 1.04.

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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