Example 1.3The blades of a wind turbine turn a large shaft at a relatively slow speed. Therotational speed is increased by a gearbox that has an efficiency of 0.93. In turn, thegearbox output shaft drives an electric generator with an efficiency of 0.95. Thecylindrical nacelle, which houses the gearbox, generator, and associated equipment,is of length L = 6 m and diameter D= 3 m. If the turbine produces P = 2.5 MW ofelectrical power, and the air and surroundings temperatures are T = 25 °C and Tsur =20 °C, respectively, determine the minimum possible operating temperature insidethe nacelle. The emissivity of the nacelle is 0.83, and the convective heat transfercoefficient is h = 35 W/m² K. The surface of the nacelle that is adjacent to the bladehub can be considered to be adiabatic, and solar irradiation may be neglected.Use Fin or N number of fins to reduce the Ts of thenacelle less than 143 °CT-20°CHubA-35 W7,-0.83Generator,-0.95Garb-0.93

Answered: Image /qna-images/answer/1eaca2c3-d419-45b5-af1d-3b228b7a56df.jpg

Answered: Example 1.3 The blades of a wind…

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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