International Scientific Journal


Performance characteristics of fans are generally provided for the normal temperature and pressure conditions (tI = 20 °C, pI = 101.325 kPa, ρI = 1.2 kg/m3). Very often, fans operate in different air conditions, occasionally at different air temperatures. In these cases, equations obtained by the law of similarity are usually used for recalculation of the fan operating parameters. Increasing the inlet air temperature causes a decrease in the characteristic of Reynolds number, and may lead to efficiency lowering of the fan. There are also some empirical formulas for recalculation of fan efficiency, when operating at different air temperatures. In this paper, the common way for obtaining fan performance for different operating conditions (air temperature changing) is presented. The results, obtained by recalculation of fan parameters using a law of similarity, are compared to numerical simulation results of the axial-flow fan operating with different air temperatures. These results are compared with results obtained by some recommended empirical formulas, as well. This paperwork is limited to low-pressure and mid-pressure fans, which represents the majority of all fans used in practice, for different purposes.
PAPER REVISED: 2016-07-18
PAPER ACCEPTED: 2016-09-26
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THERMAL SCIENCE YEAR 2016, VOLUME 20, ISSUE Supplement 5, PAGES [S1435 - S1447]
  1. Bogdanović, B., et al., Fans - Performance and Operating Characteristics (in Serbian), Faculty of Mechanical Engineering Nis, Nis, Serbia, 2012
  2. Babić, M., Stojković, S., Basics of Turbomachinery: Operating Principles and Mathematical Modeling (in Serbian), University of Kragujevac, Scientific Paper, Belgrade, 1990
  3. Wallis, R. A., Axial Flow Fans and Ducts, Wiley Interscience Publications, New York, USA, 1983
  4. Solomahova, T. S., Cebejseva, K. B., Centrifugal Fans (in Russian), Mechanical Engineering, Moscow, 1980
  5. Еck, B., Fans-Design and Operation of Centrifugal, Axial-Flow and Cross-Flow Fans, Paramount Press, Oxford, UK, 1973
  6. Bogdanovic, B, et al., Low-Pressure Axial Fan Designed with Different Specific Work of Elementary Stages, Thermal Science, 16 (2012), Suppl. 2, pp. S605-S615
  7. Protić, Z., et al., Novel Methods for Axial Fan Impeller Geometry Analysis and Experimental Investigations of the Generate Swirl Turbulent Flow, Thermal Science, 14 (2010), Suppl. 1, pp. S125-S139
  8. Rajvanshi, A. K., Performance Estimation of an Axial Flow Fan, IE(I) Journal-MC, 87 (2006), 2, pp. 34- 37
  9. Oh, K., Kang, S., A Numerical Investigation of the Dual Performance Characteristics of a Small Propeller fan Using Viscous Flow Calculations, Computers & Fluids, 28 (1999), 6, pp. 815-823
  10. Gabi, M., Klemm, T., Numerical and Experimental Investigations of Cross-Flow Fans, Journal of Computational and Applied Mechanics, 5 (2004), 2, pp. 251-261
  11. Fortuna, S., Sobczak, K., Numerical and Experimental Investigations of the Flow in the Radial Fan, Mechanics, 27 (2008), 4, pp. 138-143
  12. Bogdanović-Jovanović, J., et al., Numerical Simulations and Performance Prediction of Low Pressure Fan, Proceedings, XIX Procesing 2006, SMEITS, Belgrade, 2006, pp. 75-80
  13. Lin, S. C., Huang, C. L., An Integrated Experimental and Numerical Study of Forward-Curved Centrifugal fan, Experimental Thermal and Fluid Science, 26 (2002), 5, pp. 421-434
  14. Hotchkiss, P. J., et al., Numerical Investigation into the Effect of Cross-Flow on the Performance of Axial Flow Fans in Forced Draught Air-Cooled Heat Exchangers, Applied Thermal Engineering, 26 (2006), 2, pp. 200-208
  15. Stephenson, J. M., Efficiency and Drag of Axial-Flow Compressor Stage: The Connection Between the Efficiency of a Stage, the Forces on the Blade Sections and the Profile Drag; the Relation Between Different Definitions of Efficiency, and the Effect of other Sources of Loss, Aircraft Engineering and Aerospace Technology, 25 (1953), 6, pp. 158-160
  16. ***, Inspection and Performance Fan Testing (VDI - Fan Regulation, in German), VDI-2044, pp. 36, 1966
  17. Stepanoff, A., J., Turbo Blowers - Theory, Design and Application of Centrifugal and Axial Flow Compressors and Fans, John Wiley & Sons, New York, USA, 1955
  18. Ferziger, J. H., Peric, M., Computational Methods for Fluid Dynamics, 3rd Rev. ed., Springer, Heidelberg, Germany, 2002
  19. Casey, M., Best Practice Advice for Turbomachinery Internal Flows, QNET-CFD Network Newsletter (A Thematic Network For Quality and Trust in the Industrial Application of CFD), 2 (2004), 4, pp. 40-46

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