, 44:241 | Cite as

Numerical investigation to predict optimum attack angle combination of longitudinal vortex generators in compact heat exchangers for thermo-hydraulic heightened performance

  • Mohd Zeeshan
  • Sujit NathEmail author
  • Dipankar Bhanja


The current 3-D numerical analysis explores the effect of combinations of rectangular winglet pairs (RWPs) having different attack angles (i.e. 5°, 15° and 25°) along a row of the tube array, on the performance of the fin and tube heat exchanger (FTHE). The considered airside Reynolds number Re ranges from 500 to 900. In total, six combinations of three attack angle vortex generators (VGs) have been numerically analysed namely 5°-15°-25°, 5°-25°-15°, 15°-5°-25°, 15°-25°-5°, 25°-5°-15° and 25°-15°-5°. The performance of the FTHE is represented by area goodness factor. The performance rankings of the FTHEs are also obtained by the MOORA method. Finally, 5°-25°-15° case provides the best thermal hydraulic performance for which heat transfer coefficient (h) is increased by 68.20% at Re = 500 and 81.78% at Re = 900, with a significant pressure drop penalty.


Fin and tube heat exchanger rectangular vortex generators area goodness factor MOORA method 



total heat transfer surface area (m2)


minimum flow area (m2)


specific heat (J kg−1 K−1)


outer tube diameter (m)


hydraulic diameter, Dh = 4AminL/AT


friction factor


fin pitch (m)


fin thickness (m)


air-side heat transfer coefficient (W m−2 K−1)


channel height (m)


winglet height (m)


Colburn j-factor


flow length (m)


mass flow rate (kg/s)


average Nusselt number


pressure (Pa)


fan power (W)


Prandtl number


longitudinal tube pitch (m)


span wise tube pitch (m)


heat transfer capacity (W)


air side Reynolds number


Stanton number


temperature (K)


outlet temperature (K)


wall temperature (K)

\( \bar{T} \)

bulk average temperature (K)


inlet temperature (K)


mean value of temperature

\( \bar{p} \)

bulk average pressure (Pa)


air side pressure drop (Pa)


free stream velocity (ms−1)


velocity in x-direction (ms−1)


velocity in y-direction (ms−1)


mean velocity at Amin (m s−1)


velocity in z-direction (m s−1)

Greek symbols


dynamic viscosity (Pa.S)


density (kg m−3)


thermal conductivity (W m−1K−1)


fan efficiency



finned tube heat exchanger


multi-objective optimization on the basis of ratio analysis


rectangular winglet pair


longitudinal vortex generators


common flow down


common flow up


  1. 1.
    Jacobi A M and Shah R K 1995 Heat transfer surface enhancement through the use of longitudinal vortices: a review of recent progress. Experimental Thermal and Fluid Science 11: 295–309CrossRefGoogle Scholar
  2. 2.
    Bendaoud A L, Ouzzane M, Aidoun Z and Galanis N 2011 A novel approach to study the performance of finned-tube heat exchangers under frosting conditions. Journal of Applied Fluid Mechanics 4: 9–20Google Scholar
  3. 3.
    Yoo S Y, Park D S and Chung M H 2002 Heat transfer enhancement for fin-tube heat exchanger using vortex generators. KSME International Journal 16: 109–115CrossRefGoogle Scholar
  4. 4.
    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. Applied Thermal Engineering 29: 859–876CrossRefGoogle Scholar
  5. 5.
    Huisseune H, Joen C T, Jaeger P, De Ameel B, Schampheleire S D and Paepe M D 2013 Influence of the louver and delta winglet geometry on the thermal hydraulic performance of a compound heat exchanger. International Journal of Heat and Mass Transfer 57: 58–72CrossRefGoogle Scholar
  6. 6.
    Tiwari S, Maurya D and Eswaran V 2003 Heat transfer enhancement in cross-flow heat exchangers using oval tubes and multiple delta winglets. International Journal of Heat and Mass Transfer 46: 2841–2856CrossRefGoogle Scholar
  7. 7.
    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. International Journal of Heat and Mass Transfer 47: 4327–4338CrossRefGoogle Scholar
  8. 8.
    Joardar A and Jacobi A M 2008 Heat transfer enhancement by winglet-type vortex generator arrays in compact plain-fin-and-tube heat exchangers. International Journal of Refrigeration 31: 87–97CrossRefGoogle Scholar
  9. 9.
    Kumar A, Joshi J B, Nayak A K and Vijayan P K 2015 A review on the thermal hydraulic characteristics of the air-cooled heat exchangers in forced convection. Sādhanā 3(40): 673–755CrossRefGoogle Scholar
  10. 10.
    Arshad H, Khushnood S, Nizam L A, Ahsan M A and Bhatti O G 2018 Effect of fin geometry on flow-induced vibration response of a finned tube in a tube bundle. Journal of Applied Fluid Mechanics 11(40): 1143–1152Google Scholar
  11. 11.
    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. International Journal of Heat and Mass Transfer 51: 1179–1191CrossRefGoogle Scholar
  12. 12.
    Lin C N, Liu Y W and Leu J S 2008 Heat transfer and fluid flow analysis for plate-fin and oval tube heat exchangers with vortex generators. Heat Transfer Engineering 29(7): 588–596CrossRefGoogle Scholar
  13. 13.
    He Y L, Han H, Tao W Q and Zhang Y W 2012 Numerical study of heat-transfer enhancement by punched winglet-type vortex generator arrays in fin-and-tube heat exchangers. International Journal of Heat and Mass Transfer 55: 5449–5458CrossRefGoogle Scholar
  14. 14.
    He Y L, Chu P, Tao W, Zhang Y W and Xie T 2013 Analysis of heat transfer and pressure drop for fin-and-tube heat exchangers with rectangular winglet-type vortex generators. Applied Thermal Engineering 61: 770–783CrossRefGoogle Scholar
  15. 15.
    Zeeshan M, Hazarika S A, Nath S and Bhanja D 2017 Numerical investigation on the performance of fin and tube heat exchangers using rectangular vortex generators. AIP Conference Proceedings (1859): 020011CrossRefGoogle Scholar
  16. 16.
    Zeeshan M, Nath S, Bhanja D and Das A 2018 Numerical investigation for the optimal placements of rectangular vortex generators for improved thermal performance of fin-and-tube heat exchangers. Applied Thermal Engineering 136: 589–601CrossRefGoogle Scholar
  17. 17.
    Sinha A M, Chattopadhyay H, Iyengar A K and Biswas G 2016 Enhancement of heat transfer in a fin-tube heat exchanger using rectangular winglet type vortex generators. International Journal of Heat and Mass Transfer 101: 667–681CrossRefGoogle Scholar
  18. 18.
    Sharma B, Bhushan G and Sachdeva G 2017 Effect of flow structure on heat transfer in compact heat exchanger by using finite thickness winglet at acute angle. Journal of Thermal Engineering 3(2): 1149–1162CrossRefGoogle Scholar
  19. 19.
    Sarangi S K and Mishra D P 2017 Effect of winglet location on heat transfer of a fin and-tube heat exchanger. Applied Thermal Engineering 116: 528–540CrossRefGoogle Scholar
  20. 20.
    Lin C N and Jhang J Y 2002 Conjugate heat transfer and fluid flow analysis in fin-tube heat exchangers with wave-type vortex generators. Journal Enhanced Heat Transfer 9: 123–136CrossRefGoogle Scholar
  21. 21.
    Valentino M I, Tran L V, Ricklick M and Kapat J S 2012 A study of heat transfer augmentation for recuperative heat exchangers: comparison between three dimple geometries. Journal of Engineering for Gas Turbines and Power 134(072303): 1–9Google Scholar
  22. 22.
    Wang C C, Chen K Y, Liaw J S and Tseng C Y 2015 An experimental study of the air-side performance of fin-and-tube heat exchangers having plain, louver, and semi-dimple vortex generator configuration. International Journal of Heat and Mass Transfer 80: 281–287.CrossRefGoogle Scholar
  23. 23.
    Gholami A A, Wahid M A and Mohammed H A 2014 Heat transfer enhancement and pressure drop for fin-and-tube compact heat exchangers with wavy rectangular winglet-type vortex generators. International Communications in Heat and Mass Transfer 54: 132–140CrossRefGoogle Scholar
  24. 24.
    Oneissi M, Habchi C, Russeil S, Bougeard D and Lemenand T 2016 Novel design of delta winglet pair vortex generator for heat transfer enhancement. International Journal of Thermal Sciences 109: 1–9CrossRefGoogle Scholar
  25. 25.
    Lu G and Zhou G 2016 Numerical simulation on performances of plane and curved winglet type vortex generator pairs with punched holes. International Journal of Heat and Mass Transfer 102: 679–690CrossRefGoogle Scholar
  26. 26.
    Song K W, Xi Z P, Su M, Wang L C, Wu X and Wang L B 2017 Effect of geometric size of curved delta winglet vortex generators and tube pitch on heat transfer characteristics of fin-tube heat exchanger. Experimental Thermal and Fluid Science 82: 8–18CrossRefGoogle Scholar
  27. 27.
    Zeeshan M, Nath S and Bhanja D 2017 Numerical study to predict optimal configuration of fin and tube compact heat exchanger with various tube shapes and spatial arrangements. Energy Conversion and Management 148: 737–752CrossRefGoogle Scholar
  28. 28.
    Zeeshan M, Nath S and Bhanja D 2019 Determination of optimum winglet height of longitudinal vortex generators for the best thermo-hydraulic performance of compact heat exchangers. Journal of Mechanical Science and Technology 33(9): 4529–4534CrossRefGoogle Scholar
  29. 29.
    Sun L and Zhang C L 2014 Evaluation of elliptical finned-tube heat exchanger performance using CFD and response surface methodology. International Journal of Thermal Sciences 75: 45–53CrossRefGoogle Scholar

Copyright information

© Indian Academy of Sciences 2019

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringNational Institute of Technology SilcharSilcharIndia

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