Aerodynamic Design of a transonic axial Fan with Low Aspect Ratio and Validating

Author

School of Mechanical Engineering, Arak University of Technology, Arak, Iran.

Abstract

In recent years trends towards designing axial fan with low aspect ratio have been increased. Application of this kind of blades leads to higher rotor efficiency relative to blade with high aspect ratios. In contrast, applying this kind of blade causes to intensify 3D flows, increasing secondary losses and creating losses due to shock occurrence. In the current study, designing of a two stage axial fan with low aspect ratio is carried out. To obtain losses in the axial fan, appropriate models have been employed for profile loss, secondary loss shock loss and tip clearance loss. For extracting blade’s profile, polynomial camber and naca 65 thickness distribution have been used. Comparing the obtained results including loss estimation, meridional velocity, pressure and diffusion factor distribution and blade geometrical parameters such as stagger angle, chord length, solidity and camber angle show good agreement. The 3D shape of the blade have been extracted by calculating the stagger angle and thickness distribution in each section.

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References

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Journal of Solid and Fluid Mechanics
Volume 9, Issue 1
April 2019
Pages 251-264

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