0
Research Papers: Flows in Complex Systems

Lift and Drag Characteristics of an Air-Cooled Heat Exchanger Axial Flow Fan

[+] Author and Article Information
Francois G. Louw

Department of Mechanical
and Mechatronic Engineering,
Stellenbosch University,
Stellenbosch 7600, Republic of South Africa
e-mail: francoisl@sun.ac.za

Theodore W. von Backström

Professor
Department of Mechanical
and Mechatronic Engineering,
Stellenbosch University,
Stellenbosch 7600, Republic of South Africa
e-mail: twvb@sun.ac.za

Sybrand J. van der Spuy

Senior Lecturer
Department of Mechanical
and Mechatronic Engineering,
Stellenbosch University,
Stellenbosch 7600, Republic of South Africa
e-mail: sjvdspuy@sun.ac.za

Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received July 2, 2014; final manuscript received March 9, 2015; published online April 28, 2015. Assoc. Editor: Edward M. Bennett.

J. Fluids Eng 137(8), 081101 (Aug 01, 2015) (9 pages) Paper No: FE-14-1348; doi: 10.1115/1.4030165 History: Received July 02, 2014; Revised March 09, 2015; Online April 28, 2015

Actuator-disk models (ADMs) use blade element theory to numerically simulate the flow field induced by axial fans. These models give a fair approximation at near design flow rates, but are of poor accuracy at low flow rates. Therefore, the lift/drag (LD) characteristics of two-dimensional (2D) sections along the span of an air-cooled heat exchanger (ACHE) axial fan are numerically investigated, with the future prospect of improving ADMs at these flow conditions. It is found that the blade sectional LD characteristics are similar in shape, but offset from the 2D LD characteristics of the reference airfoil (NASA LS 413 profile) at small angles of attack (αatt<5deg). A deviation between these characteristics is observed at higher angles of attack. The blade sectional lift coefficients for αatt>5deg always remain lower compared to the maximum lift coefficient of the reference airfoil. Conversely, the blade sectional drag coefficients are always higher compared to that of the reference airfoil for αatt>5deg.

FIGURES IN THIS ARTICLE
<>
Copyright © 2015 by ASME
Your Session has timed out. Please sign back in to continue.

References

Owen, M. T. F., 2010, “A Numerical Investigation of Air-Cooled Steam Condenser Performance Under Windy Conditions,” Masters thesis, University of Stellenbosch, Stellenbosch, Republic of South Africa.
Gao, X. F., Zhang, C. W., Wei, J. J., and Yu, B., 2010, “Performance Prediction of an Improved Air-Cooled Steam Condenser With Deflector Under Strong Wind,” Appl. Therm. Eng., 30(17–18), pp. 2663–2669. [CrossRef]
Yang, L., Du, X., and Yang, Y., 2012, “Wind Effect on the Thermo-Flow Performances and Its Decay Characteristics for Air-Cooled Condensers in a Power Plant,” Int. J. Therm. Sci., 53, pp. 175–187. [CrossRef]
Corsini, A., and Rispoli, F., 2004, “Using Sweep to Extend the Stall-Free Operational Range in Axial Fan Rotors,” Proc. Inst. Mech. Eng. Part A J. Power Energy, 218(3), pp. 129–139. [CrossRef]
Vad, J., Kwedikha, A. R. A., and Jaberg, H., 2006, “Effects of Blade Sweep on the Performance Characteristics of Axial Flow Turbomachinery Rotors,” Proc. Inst. Mech. Eng. Part A J. Power Energy, 220(7), pp. 737–749. [CrossRef]
Corsini, A., Delibra, G., and Sheard, A. G., 2013, “On the Role of Leading-Edge Bumps in the Control of Stall Onset in Axial Fan Blades,” ASME J. Fluids Eng., 135(8), p. 81104. [CrossRef]
Van der Spuy, S. J., Von Backström, T. W., and Kröger, D. G., 2009, “Performance of Low-Noise Fans in Power Plant Air-Cooled Steam Condensers,” Noise Control Eng., 57(4), pp. 1–7. [CrossRef]
Thiart, G. D., 1990, “A Numerical Procedure for Predicting the Effects of Distorted Inflow Conditions on the Performance of Axial Flow Fans,” Ph.D. thesis, University of Stellenbosch, Stellenbosch, Republic of South Africa.
Bredell, J., Kroger, D. G., and Thiart, G., 2006, “Numerical Investigation of Fan Performance in a Forced Draft Air-Cooled Steam Condenser,” Appl. Therm. Eng., 26(8–9), pp. 846–852. [CrossRef]
Van Rooyen, J. A., and Kröger, D. G., 2008, “Performance Trends of an Air-Cooled Steam Condenser Under Windy Conditions,” ASME J. Eng. Gas Turbines Power, 130(2), p. 023006. [CrossRef]
Meyer, C. J., and Kröger, D. G., 2001, “Numerical Simulation of the Flow Field in the Vicinity of an Axial Flow Fan,” Int. J. Numer. Methods Fluids, 36(8), pp. 947–969. [CrossRef]
Duvenhage, K., Vermeulen, J. A., Meyer, C. J., and Kröger, D. G., 1996, “Flow Distortions at the Fan Inlet of Forced-Draft Air-Cooled Heat Exchangers,” Appl. Therm. Eng., 16(8–9), pp. 741–752. [CrossRef]
Van der Spuy, S. J., 2011, “Perimeter Fan Performance in Forced Draft Air-Cooled Steam Condensers,” Ph.D. thesis, University of Stellenbosch, Republic of South Africa.
McGhee, R. J., and Beasley, W. D., 1976, “Effects of Thickness on the Aerodynamic Characteristics of an Initial Low-Speed Family of Airfoils for General Aviation Applications,” National Aeronautics and Space Administration, Langley Research Center, Hampton, VA, Technical Report No. NASA TM X-72843.
Himmelskamp, H., 1947, “Profile Investigations on a Rotating Airscrew,” Ph.D. thesis, University of Göttingen, Germany.
Yu, G., Shen, X., Zhu, X., and Du, Z., 2011, “An Insight Into the Separate Flow and Stall Delay for HAWT,” Renew. Energy, 36(1), pp. 69–76. [CrossRef]
Johansen, J., and Sorensen, N. N., 2004, “Aerofoil Characteristics From 3D CFD Rotor Computations,” Wind Energy, 7(4), pp. 283–294. [CrossRef]
Tangler, J. L., 2004, “Insight Into Wind Turbine Stall and Post-Stall Aerodynamics,” Wind Energy, 7(3), pp. 247–260. [CrossRef]
Carcangiu, C. E., Sørensen, J. N., Cambuli, F., and Mandas, N., 2007, “CFDRANS Analysis of the Rotational Effects on the Boundary Layer of Wind Turbine Blades,” J. Phys. Conf. Ser., 75, p. 012031. [CrossRef]
Louw, F. G., Von Backström, T. W., and Van der Spuy, S. J., 2014, “Investigation of the Flow Field in the Vicinity of an Axial Flwo Fan During Low Flow Rates,” ASME Paper No. GT2014-25927. [CrossRef]
Louw, F. G., Bruneau, P. R. P., Von Backström, T. W., and Van der Spuy, S. J., 2012, “The Design of an Axial Flow Fan for Application in Large Air-Cooled Heat Exchangers,” ASME Paper No. GT2012-69733. [CrossRef]
Shih, T.-H., Liou, W. W., Shabbir, A., Yang, Z., and Zhu, J., 1995, “A New k-ε Eddy-Viscosity model for High Reynolds Number Turbulent Flows—Model Development and Validation,” Comp. Fluids, 24(3), pp. 227–238. [CrossRef]
Hurault, J., Kouidri, S., Bakir, F., and Rey, R., 2010, “Experimental and Numerical Study of the Sweep Effect on Three-Dimensional Flow Downstream of Axial Flow Fans,” Flow Meas. Instrum., 21(2), pp. 155–165. [CrossRef]
Borello, D., Corsini, A., Delibra, G., Fiorito, M., and Sheard, A. G., 2013, “Large-Eddy Simulation of a Tunnel Ventilation Fan,” ASME J. Fluids Eng., 135(7), p. 71102. [CrossRef]

Figures

Grahic Jump Location
Fig. 2

B2a-fan. Adapted from Ref. [20].

Grahic Jump Location
Fig. 3

Computational domain for CFD modeling. Adapted from Ref. [20].

Grahic Jump Location
Fig. 4

Comparison between experimentally and numerically obtained values for the fan performance characteristic in the form of the fan static pressure coefficient, ΨFs and fan static efficiency, ηFs. Adapted from Ref. [20].

Grahic Jump Location
Fig. 5

Depiction of B2a-fan blade sector, velocity triangles and the data sampling locations

Grahic Jump Location
Fig. 6

Flow chart depicting the Python routine used for data analyses

Grahic Jump Location
Fig. 7

Time dependent LD coefficients for blade sections at: (a) sdim = 0.1, (b) sdim = 0.5, and (c) sdim = 0.9

Grahic Jump Location
Fig. 8

Dimensionless velocity components and the angle of attack compared to dimensionless span for a range of flow coefficients

Grahic Jump Location
Fig. 9

Surface limiting streamlines for Φd=0.168

Grahic Jump Location
Fig. 10

Surface limiting streamlines for Φ=0.048

Grahic Jump Location
Fig. 11

Numerically obtained LD coefficients of various blade span sectional profiles compared to flow coefficient

Grahic Jump Location
Fig. 12

LD coefficients compared to dimensionless span for a range of flow coefficients

Grahic Jump Location
Fig. 13

Numerically obtained LD coefficients of various blade span sectional profiles compared to the NASA LS 413 [14] airfoil profile

Tables

Errata

Discussions

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 Journal Articles
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