An axial flow fan 1.83 m diameter is designed to run at a speed of 1400 rpm with an average axial air velocity of 12.2 m/s. A quarter scale model has been built to obtain a check on the design and the rotational speed of the model fan is 4200 rpm. Determine the axial air velocity of the model so that dynamical similarity with the full-scale fan is preserved. The effects of Reynolds number change may be neglected. A sufficiently large pressure vessel becomes available in which the complete model can be placed and tested under conditions of complete similarity. The viscosity of the air is independent of pressure and the temperature is maintained constant. At what pressure must the model be tested?

An axial flow fan 1.83 m diameter is designed to run at a speed of 1400 rpm with an average axial air velocity of 12.2 m/s. A quarter scale model has been built to obtain a check on the design and the rotational speed of the model fan is 4200 rpm. Determine the axial air velocity of the model so that dynamical similarity with the full-scale fan is preserved. The effects of Reynolds number change may be neglected. A sufficiently large pressure vessel becomes available in which the complete model can be placed and tested under conditions of complete similarity. The viscosity of the air is independent of pressure and the temperature is maintained constant. At what pressure must the model be tested?

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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Concept explainers

Applied Fluid Mechanics

A fluid is a substance that is continuously deformed by the application of shear stress. The rate of deformation of a fluid depends on its viscosity. The fluid tries to flow when it interacts with some other system.

Question

2.
An axial flow fan 1.83 m diameter is designed to run at a speed of 1400 rpm with an average
axial air velocity of 12.2 m/s. A quarter scale model has been built to obtain a check on the
design and the rotational speed of the model fan is 4200 rpm. Determine the axial air velocity
of the model so that dynamical similarity with the full-scale fan is preserved. The effects of
Reynolds number change may be neglected. A sufficiently large pressure vessel becomes
available in which the complete model can be placed and tested under conditions of complete
similarity. The viscosity of the air is independent of pressure and the temperature is
maintained constant. At what pressure must the model be tested?

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