0

Full Content is available to subscribers

Subscribe/Learn More  >

CFD Analysis of the Non-Uniform Velocity Distribution Generated by a Large Axial Flow Fan

[+] Author Affiliations
Hongliang Lu, Xiaolong Xue, Xiaoying Tang, Xuefeng Geng, Jianping Yao

Shanghai Institute of Special Equipment Inspection and Technical Research, Shanghai, China

Paper No. PVP2015-45482, pp. V004T04A055; 4 pages
doi:10.1115/PVP2015-45482
From:
  • ASME 2015 Pressure Vessels and Piping Conference
  • Volume 4: Fluid-Structure Interaction
  • Boston, Massachusetts, USA, July 19–23, 2015
  • Conference Sponsors: Pressure Vessels and Piping Division
  • ISBN: 978-0-7918-5697-0
  • Copyright © 2015 by ASME

abstract

The air flow propelled by an axial flow fan is often assumed to be uniform across the tube bundle of an industrial air-cooled heat exchanger, but the fact is that the air flow is non-uniform in practice to the extent that as much as 35% performance of air-cooled heat exchangers is cut off. Besides the structure of tube bundle, the high flux and low pressure head fan with 1.5 m to 4.5 m in diameter is the primary reason of the air flow maldistribution. CFD was employed to numerically simulate the non-uniform air flow distribution produced by the fan in the radial and flow direction. One axial flow type fan with 3 blades about 2 m in diameter was investigated under the angular speed of 80, 350 revolutions per minute. Given that the uniform velocity is the default for the velocity or mass flow boundary, the boundary of the total pressure inlet and the static outlet was adopted in the present work for axial flow fan simulation. Between the rotating zone and the other zones is the fluid to fluid type interface with frozen rotor. The result showed that the air velocity rises when it comes nearer to the fan either in the upstream or in the downstream direction. The upstream flow decreases more rapidly than the downstream flow, the upstream velocity air at Z=−1.5 m is almost the same with the ambient while the downstream velocity at Z=5.8 m is still 2, 6 times larger than the ambient for 80, 350 RPM respectively. In each plane, the air flow distribution from the rotating center of the fan to the circumference is different from each other plane by the boundary conditions. And the maximum velocity locates at about the radial middle part of the blades. The hub at the central part near the fan causes the concave velocity distribution of the downstream flow. It is the driver mechanism geometry that causes the radial velocity change of the upstream flow. Finally, 3 methods involving the upstream or downstream type and the blade angle of inclination are provided to reduce the air flow non-uniformity.

Copyright © 2015 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In