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Research Papers: Heat Exchangers

# Investigation of Vortex Generator Enhanced Double-Fin and Tube Heat Exchanger

[+] Author and Article Information
Shobhana Singh

Department of Energy Technology,
Aalborg University,
Pontoppidanstræde 111,
Aalborg East 9220, Denmark
e-mail: ssi@et.aau.dk

Kim Sørensen

Department of Energy Technology,
Aalborg University,
Pontoppidanstræde 111,
Aalborg East 9220, Denmark

Thomas Condra

Department of Energy Technology,
Aalborg University,
Pontoppidanstræde 111,
Aalborg East 9220, Denmark

1Corresponding author.

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received March 23, 2018; final manuscript received November 7, 2018; published online December 13, 2018. Assoc. Editor: Danesh K. Tafti.

J. Heat Transfer 141(2), 021802 (Dec 13, 2018) (13 pages) Paper No: HT-18-1172; doi: 10.1115/1.4042050 History: Received March 23, 2018; Revised November 07, 2018

## Abstract

In the present work, a numerical analysis of conjugate heat transfer and fluid flow in vortex generator (VG) enhanced double-fin and tube heat exchanger is carried out. The enhanced design aims to improve the heat transfer performance of a conventional double-fin and tube heat exchanger for waste heat recovery applications. A three-dimensional (3D) numerical model is developed using ANSYS cfx to simulate fluid flow and conjugate heat transfer process. Numerical simulations with rectangular winglet vortex generators (RWVGs) at five different angles of attack ($−20deg≤α≤20deg$) are performed for the Reynolds number range of $5000≤Re≤11,000$. Salient performance characteristics are analyzed in addition to the temperature distribution and flow fields. Based on the numerical results, it is concluded that the overall performance of the double-fin and tube heat exchanger can be improved by 27–91% by employing RWVGs at $α=−20deg$ for the range of Reynolds number investigated. The study provides useful design information and necessary performance data that can be adopted for the design development of the heat exchanger at a lower manufacturing cost.

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## References

Singh, S. , Sørensen, K. , and Condra, T. J. , 2017, “ Investigation of Material Efficient Fin Patterns for Cost-Effective Operation of Fin and Tube Heat Exchanger,” Appl. Therm. Eng., 126(11), pp. 903–914.
Bergles, A. E. , Webb, R. L. , and Junkhan, G. H. , 1979, “ Energy Conservation Via Heat Transfer Enhancement,” Energy, 4(2), pp. 193–200.
Bergles, A. E. , 1997, “ Heat Transfer Enhancement—The Encouragement and Accommodation of High Heat Fluxes,” ASME J. Heat Transfer, 119(1), pp. 8–19.
Steinke, M. E. , and Kandlikar, S. G. , 2004, “ Review of Single-Phase Heat Transfer Enhancement Techniques for Application in Microchannels, Minichannels and Microdevices,” Int. J. Heat Technol., 22(2), pp. 3–11.
Bergles, A. E. , 2002, “ ExHFT for Fourth Generation Heat Transfer Technology,” Exp. Therm. Fluid Sci., 26(2–4), pp. 335–344.
Garimella, S. V. , and Eibeck, P. A. , 1991, “ Enhancement of Single Phase Convective Heat Transfer From Protruding Elements Using Vortex Generators,” Int. J. Heat Mass Transfer, 34(9), pp. 2431–2433.
Fiebig, M. , 1998, “ Vortices, Generators and Heat Transfer,” Chem. Eng. Res. Des., 76(2), pp. 108–123.
Urkiola, A. , Fernandez-Gamiz, U. , Errasti, I. , and Zulueta, E. , 2017, “ Computational Characterization of the Vortex Generated by a Vortex Generator on a Flat Plate for Different Vane Angles,” Aerosp. Sci. Technol., 65, pp. 18–25.
Ghanem, A. , Habchi, C. , Lemenand, T. , Valle, D. D. , and Peerhossaini, H. , 2013, “ Energy Efficiency in Process Industry-High-Efficiency Vortex (HEV) Multifunctional Heat Exchanger,” Renewable Energy, 56, pp. 96–104.
Biswas, G. , Mitra, N. K. , and Fiebig, M. , 1994, “ Heat Transfer Enhancement in Fin-Tube Heat Exchangers by Winglet Type Vortex Generators,” Int. J. Heat Mass Transfer, 37(2), pp. 283–291.
Fiebig, M. , 1995, “ Embedded Vortices in Internal Flow: Heat Transfer and Pressure Loss Enhancement,” Int. J. Heat Fluid Flow, 16(5), pp. 376–388.
Fiebig, M. , Valencia, A. , and Mitra, N. K. , 1994, “ Local Heat Transfer and Flow Losses in Fin-and-Tube Heat Exchangers With Vortex Generators: A Comparison of Round and Flat Tubes,” Exp. Therm. Fluid Sci., 8(1), pp. 35–45.
Tiggelbeck, S. , Mitra, N. K. , and Fiebig, M. , 1992, “ Flow Structure and Heat Transfer in a Channel With Multiple Longitudinal Vortex Generators,” Exp. Therm. Fluid Sci., 5(4), pp. 425–436.
Tiggelbeck, S. , Mitra, N. K. , and Fiebig, M. , 1993, “ Experimental Investigations of Heat Transfer Enhancement and Flow Losses in a Channel With Double Rows of Longitudinal Vortex Generators,” Int. J. Heat Mass Transfer, 36(9), pp. 2327–2337.
Fiebig, M. , Valencia, A. , and Mitra, N. K. , 1993, “ Wing-type Vortex Generators for Fin-and-Tube Heat Exchangers,” Exp. Therm. Fluid Sci., 7(4), pp. 287–295.
Joardar, A. , and Jacobi, A. M. , 2008, “ Heat Transfer Enhancement by Winglet-Type Vortex Generator Arrays in Compact Plain-Fin-and-Tube Heat Exchangers,” Int. J. Refrig., 31(1), pp. 87–97.
He, J. J. , Liu, L. L. , and Jacobi, A. M. , 2010, “ Air-Side Heat-Transfer Enhancement by a New Winglet-Type Vortex Generator Array in a Plain-Fin Round-Tube Heat Exchanger,” ASME J. Heat Transfer, 132(7), p. 071801.
Jacobi, A. M. , and Shah, R. K. , 1995, “ Heat Transfer Surface Enhancement Through the Use of Longitudinal Vortices: A Review of Recent Progress,” Exp. Therm. Fluid Sci., 11(3), pp. 295–309.
Turk, A. Y. , and Junkhan, G. H. , 1986, “ Heat Transfer Enhancement Downstream of Vortex Generators on a Flat Plate,” Eighth International Heat Transfer Conference, San Francisco, CA, Aug. 17–22, pp. 2903–2908.
Jang, J. Y. , Hsu, L. F. , and Leu, J. S. , 2013, “ Optimization of the Span Angle and Location of Vortex Generators in a Plate-Fin and Tube Heat Exchanger,” Int. J. Heat Mass Transfer, 67, pp. 432–444.
Liou, T. M. , Chen, C. C. , and Tsai, T. W. , 2000, “ Heat Transfer and Fluid Flow in a Square Duct With 12 Different Shaped Vortex Generators,” ASME J. Heat Transfer, 122(2), pp. 327–335.
Li, L. , Du, X. , Zhang, Y. , Yang, L. , and Yang, Y. , 2015, “ Numerical Simulation on Flow and Heat Transfer of Fin-and-Tube Heat Exchanger With Longitudinal Vortex Generators,” Int. J. Therm. Sci., 92, pp. 85–96.
Chu, P. , He, Y. L. , Lei, Y. G. , Tian, L. T. , and Li, R. , 2009, “ Three-Dimensional Numerical Study on Fin-and-Oval-Tube Heat Exchanger With Longitudinal Vortex Generators,” Appl. Therm. Eng., 29(5–6), pp. 859–876.
Tian, L. , He, Y. , Chu, P. , and Tao, W. , 2009, “ Numerical Study of Flow and Heat Transfer Enhancement by Using Delta Winglets in a Triangular Wavy Fin-and-Tube Heat Exchanger,” ASME J. Heat Transfer, 131(9), p. 091901.
Salviano, L. O. , Dezan, D. J. , and Yanagihara, J. I. , 2015, “ Optimization of Winglet-Type Vortex Generator Positions and Angles in Plate-Fin Compact Heat Exchanger: Response Surface Methodology and Direct Optimization,” Int. J. Heat Mass Transfer, 82, pp. 373–387.
Chen, Y. , Fiebig, M. , and Mitra, N. K. , 2000, “ Heat Transfer Enhancement of Finned Oval Tubes With Staggered Punched Longitudinal Vortex Generators,” Int. J. Heat Mass Transfer, 43(3), pp. 417–435.
Zhang, T. , Haung, Z. Q. , Zhang, X. B. , and Liu, C. J. , 2016, “ Numerical Investigation of Heat Transfer Using a Novel Punched Vortex Generator,” Numer. Heat Transfer, Part A: Appl., 69(10), pp. 1150–1168.
He, Y. L. , Han, H. , Tao, W. Q. , and Zang, Y. W. , 2012, “ Numerical Study of Heat-Transfer Enhancement by Punched Winglet-Type Vortex Generator Arrays in Fin-and-Tube Heat Exchangers,” Int. J. Heat Mass Transfer, 55(21–22), pp. 5449–5458.
Tian, X. L. , Jin, H. , Song, K. W. , Wang, L. C. , Liu, S. , and Wang, L. B. , 2018, “ Effects of Fin Pitch and Tube Diameter on the Air-Side Performance of Tube Bank Fin Heat Exchanger With the Fins Punched Plane and Curved Rectangular Vortex Generators,” Exp. Heat Transfer, 31(4), pp. 297–316.
Välikangas, T. , Singh, S. , Sørensen, K. , and Condra, T. J. , 2018, “ Fin-and-Tube Heat Exchanger Enhancement With a Combined Herringbone and Vortex Generator Design,” Int. J. Heat Mass Transfer, 118, pp. 602–616.
Tao, W. Q. , He, Y. L. , Wang, Q. W. , Qu, Z. G. , and Song, F. Q. , 2002, “ A Unified Analysis on Enhancing Single Phase Convective Heat Transfer With Field Synergy Principle,” Int. J. Heat Mass Transfer, 45(24), pp. 4871–4879.
Cheng, Y. P. , Qu, Z. G. , Tao, W. Q. , and He, Y. L. , 2004, “ Numerical Design of Efficient Slotted Fin Surface Based on the Field Synergy Principle,” Numer. Heat Transf. Part A Appl., 45(6), pp. 517–538.
Cheng, Y. P. , Lee, T. S. , and Low, H. T. , 2007, “ Numerical Analysis of Periodically Developed Fluid Flow and Heat Transfer Characteristics in the Triangular Wavy Fin-and-Tube Heat Exchanger Based on Field Synergy Principle,” Numer. Heat Transfer, Part A: Appl., Int. J. Comput. Methodology, 53(8), pp. 821–842.
Jia, H. , Liu, Z. C. , Liu, W. , and Nakayama, A. , 2014, “ Convective Heat Transfer Optimization Based on Minimum Entransy Dissipation in the Circular Tube,” Int. J. Heat Mass Transfer, 73, pp. 124–129.
Wang, J. , Liu, Z. , Yuan, F. , Liu, W. , and Chen, G. , 2015, “ Convective Heat Transfer Optimization in a Circular Tube Based on Local Exergy Destruction Minimization,” Int. J. Heat Mass Transfer, 90, pp. 49–57.
Yu, H. , Wen, J. , Xu, G. , and Li, H. , 2016, “ Theoretically and Numerically Investigation About the Novel Evaluating Standard for Convective Heat Transfer Enhancement Based on the Entransy Theory,” Int. J. Heat Mass Transfer, 98, pp. 183–192.
Wu, J. M. , and Tao, W. Q. , 2008, “ Numerical Study on Laminar Convection Heat Transfer in a Rectangular Channel With Longitudinal Vortex Generator—Part A: Verification of Field Synergy Principle,” Int. J. Heat Mass Transfer, 51(5–6), pp. 1179–1191.
Singh, S. , Sørensen, K. , and Condra, T. J. , 2016, “ Influence of the Degree of Thermal Contact in Fin and Tube Heat Exchanger: A Numerical Analysis,” Appl. Therm. Eng., 107(25), pp. 612–624.
Singh, S. , Sørensen, K. , and Condra, T. J. , 2016, “ Parametric CFD Analysis to Study the Influence of Fin Geometry on the Performance of a Fin and Tube Heat Exchanger,” Nineth Eurosim Congress on Modelling and Simulation (EUROSIM), Oulu, Finland, Sept. 12–16, pp. 135–140.
Singh, S. , Sørensen, K. , Simonsen, A. S. , and Condra, T. J. , 2017, “ Implications of Fin Profiles on Overall Performance and Weight Reduction of a Fin and Tube Heat Exchanger,” Appl. Therm. Eng., 115, pp. 962–976.
Chen, H. T. , and Lai, J. R. , 2012, “ Study of Heat-Transfer Characteristics on the Fin of Two-Row Plate Finned-Tube Heat Exchangers,” Int. J. Heat Mass Transfer, 55(15–16), pp. 4088–4095.
Jin, Y. , Tang, G. H. , He, T. L. , and Tao, W. Q. , 2013, “ Parametric Study and Field Synergy Principle Analysis of H-Type Finned Tube Bank With 10 Rows,” Int. J. Heat Mass Transfer, 60, pp. 241–251.
Jin, Y. , Yu, Z. Q. , Tang, G. H. , He, T. L. , and Tao, W. Q. , 2016, “ Parametric Study and Multiple Correlations of an H-Type Finned Tube Bank in a Fully Developed Region,” Numer. Heat Transfer, Part A: Appl., 70(1), pp. 64–78.
Kazi, S. N. , 2015, “Heat Transfer Studies and Applications,” IntechOpen, London, UK.
Menter, F. R. , 1993, “ Zonal Two Equation k-u Turbulence Models for Aerodynamic Flows,” AIAA Paper No. 93-2906.
Menter, F. R. , 1994, “ Two-Equation Eddy-Viscosity Turbulence Models for Engineering Applications,” AIAA J., 38(8), pp. 1598–1605.
Nagaosa, R. S. , 2017, “ Turbulence Model-Free Approach for Predictions of Air Flow Dynamics and Heat Transfer in a Fin-and-Tube Exchange,” Energy Convers. Manage., 142, pp. 414–425.
Hirsch, C. , 1991, Numerical Computation of Internal and External Flows, Vol. 2, Wiley, New York.
Barbosa , J. R., Jr. , Hermes, C. J. L. , and Melo, C. , 2010, “ CFD Analysis of Tube-Fin “No-Frost” Evaporators,” J. Braz. Soc. Mech. Sci. Eng., 32(4), pp. 445–453.
Menter, F. R. , Kuntz, M. , and Langtry, R. , 2003, “ Ten Years of Industrial Experience With the SST Turbulence Model,” Turbul. Heat Mass Transfer, 4, pp. 625–632.
Woelke, M. , 2007, “ Eddy Viscosity Turbulence Models Employed by Computational Fluid Dynamic,” Prace Instytutu Lotnictwa, Scientific Publishers of the Institute of Aviation, Warsaw, Poland, pp. 92–113.
ANSYS CFX, 2018, “ High-Performance Computational Fluid Dynamics (CFD) Software Tool,” ANSYS, Canonsburg, PA, assessed Jan. 05, 2018,
Patankar, S. V. , 1980, Numerical Heat Transfer and Fluid Flow, Hemisphere, Washington DC.
Eça, L. , and Hoekstra, M. , 2014, “ A Procedure for the Estimation of the Numerical Uncertainty of CFD Calculations Based on Grid Refinement Studies,” J. Comput. Phys., 262, pp. 104–130.
Chen, H. , Wang, Y. , Zhao, Q. , Ma, H. , Li, Y. , and Chen, Z. , 2014, “ Experimental Investigation of Heat Transfer and Pressure Drop Characteristics of H-Type Finned Tube Banks,” Energies, 7(11), pp. 7094–7104.
Kays, W. M. , and London, A. L. , 1998, Compact Heat Exchangers, 3rd ed., Krieger Publishing Company, Malabar, FL.
Guo, Z. Y. , Li, D. Y. , and Wang, B. X. , 1998, “ A Novel Concept for Convective Heat Transfer Enhancement,” Int. J. Heat Mass Transfer, 41(14), pp. 2221–2225.
Tian, L. T. , He, Y. L. , Lei, Y. G. , and Tao, W. Q. , 2009, “ Numerical Study of Fluid Flow and Heat Transfer in a Flat Plate Channel With Longitudinal Vortex Generators by Applying Field Synergy Principle Analysis,” Int. Commun. Heat Mass Transfer, 36(2), pp. 111–120.
Shah, R. K. , and London, A. L. , 1971, “ Laminar Flow Forced Convection Heat Transfer and Flow Friction in Straight and Curved Ducts—A Summary of Analytical Solutions,” Department of Mechanical Engineering, Stanford University, Stanford, CA, Technical Report No. 75.
Leu, J. S. , Wu, Y. H. , and Jang, J. Y. , 2004, “ Heat Transfer and Fluid Flow Analysis in Plate-Fin and Tube Heat Exchangers With a Pair of Block Shape Vortex Generators,” Int. J. Heat Mass Transfer, 47(19–20), pp. 4327–4338.

## Figures

Fig. 1

A pictorial view of double-fin and tube heat exchanger

Fig. 2

Illustration of the conventional double-fin and tube heat exchanger unit: (a) conventional plain fin and (b) enhanced fin with RWVG

Fig. 3

Geometric details of the enhanced double-fin and tube heat exchanger design: (a) RWVG punched on the horizontal fin surface and (b) enhanced double-fin and tube heat exchanger with RWVGs

Fig. 4

Simulated computational geometry with set boundary conditions

Fig. 5

Illustration of the boundary layer mesh

Fig. 6

A plot of Nusselt number versus number of mesh elements

Fig. 7

The comparison of model results with the correlation values

Fig. 8

Temperature distribution on the lower fin and tube surface: (a) plain fin with no RWVG, (b) fin with RWVG at α = 0 deg, (c) fin with RWVG at α = 10 deg, (d) fin with RWVG at α = 20 deg, (e) fin with RWVG at α = −10 deg, and (f) fin with RWVG at α = −20 deg

Fig. 9

Velocity streamlines starting from the leading edge of the winglet of first pair inside the fluid domain at Re=5000: (a) fin with RWVG at α = 0 deg, (b) fin with RWVG at α = 10 deg, (c) fin with RWVG at α = 20 deg, (d) fin with RWVG at α = −10 deg, and (e) fin with RWVG at α = −20 deg

Fig. 10

Velocity streamlines at Re = 5000 on the outlet plane (x=0.15 m) of the fluid domain: (a) plain fin with no RWVG, (b) fin with RWVG at α = 0 deg, (c) fin with RWVG at α = 10 deg, (d) fin with RWVG at α = 20 deg, (e) fin with RWVG at α = −10 deg, and (f) fin with RWVG at α = −20 deg

Fig. 11

Variation of average synergy angle with the angle of attack and Reynolds number

Fig. 12

Variation in heat transfer characteristics with the angle of attack and Reynolds number: (a) Nusselt number and (b) Colburn j factor

Fig. 13

Variation in pressure loss characteristics with the angle of attack and Reynolds number: (a) Euler number and (b)friction factor

Fig. 14

Variation of the normalized volume goodness factor with the angle of attack and Reynolds number: (a) Euler number and (b) friction factor

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