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Selective Design of an Experiment for Evaluating Air–Water Hybrid Steam Condenser for Concentrated Solar Power

  • Sumer Dirbude
  • Nashith Khalifa
  • Laltu Chandra
Conference paper
Part of the Springer Proceedings in Energy book series (SPE)

Abstract

In thermal power plants water-cooled steam condenser is used to reject heat from steam at the turbine outlet. In this system, makeup water of about 1500–3000 L per MWh of electricity generation is required. Therefore, in the arid places, air-cooled condensers are recommended, especially, for concentrated solar thermal power (CSP) plants. It is reported that 10 °C rise in air temperature reduces electricity output by about 4.2% Bustamante et al. (Appl Therm Eng xxx:1–10, 2015) [1]. For steam condensation with air at a temperature of 37 °C, an exergetic efficiency of the condenser is 26% in comparison to 63% for water-cooled steam condenser Blanco-Marigorta et al. (Energy, 36:1966–1972, 2011) [2], Bustamante et al. (Appl Therm Eng xxx:1–10, 2015) [1]. Therefore, air-cooled condenser needs higher initial temperature difference (ITD) between condensing steam and air to achieve a high power output. In dry and hot places, like Rajasthan in India, during summer, air temperature reaches up to 45–50 °C. Whereas, condensing steam at the exit of turbine is available at a pressure of ~0.1 atm and at a temperature of ~45 °C. In view of this, the paper presents design of an experiment for evaluation of an air–water hybrid steam condenser. The proposed concept is based on: (a) the temperature difference between air and condensing steam in dry and arid regions and (b) achieving a high value of Nusselt/Colburn-factor to friction-factor ratio. A plate fin-and-circular tube with staggered arrangement air-cooled condenser designs is selected, as the starting point. Two possible modifications are suggested: (a) Earth (underground) for pre-cooling of ambient air or water and (b) use of water spray for additional cooling of the pre-cooled air. The obtained cold air is employed for heat transfer in condenser. In this paper, the selection and evaluation of characteristic design parameters are presented. Finally, the designed experimental setup using all these aspects is described.

Keywords

Experimental design Concentrated solar power Air–water hybrid condenser Heat transfer Pressure drop 

Nomenclature

D

Characteristic dimension

f

Friction factor \(= \Delta p/\frac{1}{2}\rho U_{\hbox{max} }^{2} \left( {L/D} \right)\)

h

Heat transfer coefficient

j

Colburn heat transfer coefficient = \({Nu}/{Re} \Pr^{1/3}\)

k

Thermal conductivity of fluid

N

Number of tube rows

Nu

Nusselt Number \(= hD/k\)

\(P_{\text{f}} /D\)

Fin pitch to tube collar diameter ratio

\(P_{\text{l}} /D\)

Longitudinal tube pitch to tube collar diameter ratio

Pr

Prandtl number

\(P_{\text{t}} /D\)

Transverse tube pitch to tube collar diameter ratio

\({Re}_{D}\)

Reynolds number (tube collar diameter D) \(= \rho UD/\mu\)

RH

Relative humidity (%)

α

Half contraction cone angle

β

Half diffuser angle

\(\theta\)

Full-spray cone angle

\(\rho_{\text{m}}\)

Water vapor + dry-air mixture density

\(\delta_{\text{f}}\)

Fin thickness

\(\Delta_{\text{p}}\)

Pressure drop

Triangular cross-section

~

Sinusoidal cross-section

References

  1. 1.
    J.G. Bustamante, A.S. Rattner, S. Garimella, Achieving near-water-cooled power plant performance with air-cooled condensers. Appl. Therm. Eng. xxx:1–10, (2015). http://dx.doi.org/10.1016/j.applthermaleng.2015.05.065
  2. 2.
    A.M. Blanco-Marigorta, M.V. Sanchez-Henríquez, J.A. Peňa-Quintana, Exergetic comparison of two different cooling technologies for the power cycle of a thermal power plant. Energy 36, 1966–1972 (2011)CrossRefGoogle Scholar
  3. 3.
    H.L. Zhang, J. Baeyens, J. Degŕeve, G. Cacères, Concentrated solar power plants: review and design methodology. Renew. Sustain. Energy Rev. 22, 466–481 (2013)Google Scholar
  4. 4.
    C. Kutscher, D. Costenaro, Assessment of evaporative cooling enhancement methods for air-cooled geothermal power plants. Geothermal Resources Council (GRC) Annual Meeting Reno, Nevada September 22–25 (2002)Google Scholar
  5. 5.
    A. Alkhedhair, Z. Guan, I. Jahn, H. Gurgenci, S. He, Water spray for pre-cooling of inlet air for natural draft dry cooling towers—experimental study. Int. J. Therm. Sci. 90, 70–78 (2015)CrossRefGoogle Scholar
  6. 6.
    J. Tissot, P. Boulet, A. Labergue, G. Castanet, F. Trinquet, L. Fournaison, Experimental study on air cooling by spray in the upstream flow of a heat exchanger. Int. J. Therm. Sci. 60, 23–31 (2012)CrossRefGoogle Scholar
  7. 7.
    S.A. El-Agouz, A.E. Kabeel, Performance of desiccant air conditioning system with geothermal energy under different climatic conditions. Energy Convers. Manage. 88, 464–475 (2014)CrossRefGoogle Scholar
  8. 8.
    L. Chandra, A. Agarwal, R.V. Maitri, P. Garg, Design and analyses of earth-air heat exchange systems for space cooling, IEEE--Third International Conference on Sustainable Energy Technologies (ICSET), Kathmandu, Nepal, pp 385–390 (2012). https://dx.doi.org/10.1109/ICSET.2012.6357430
  9. 9.
    C.C. Wang, C.T. Chang, Heat and mass transfer for plate fin-and-tube heat exchangers, with and without hydrophilic coating. Int. J Heat Mass Transf. 41, 3109–3120 (1998)CrossRefGoogle Scholar
  10. 10.
    N.H. Kim, B. Youn, R.L. Webb, Air-side heat transfer and friction correlations for plain fin-and-tube heat exchangers with staggered tube arrangements. Trans. ASME 221, 662–667 (1999)CrossRefGoogle Scholar
  11. 11.
    R.L. Webb, D.L. Gray, Heat transfer and friction correlations for plate finned tube heat exchangers having plain fins, in Proceedings of the 8th Heat Transfer Conference, pp 2745–2750 (1986)Google Scholar
  12. 12.
    C.C. Wang, K.Y. Chi, C.J. Chang, Heat transfer and friction characteristics of plain fin-and-tube heat exchangers, part II: correlation. Int. J. Heat Mass Transf. 43, 2693–2700 (1999)CrossRefGoogle Scholar
  13. 13.
    G. Xie, Q. Wang, B. Sunden, Parametric study and multiple correlations on air-side heat transfer and friction characteristics of fin-and-tube heat exchangers with large number of large-diameter tube rows. App. Therm. Engg. 29, 1–16 (2009)CrossRefGoogle Scholar
  14. 14.
    C.C. Wang, Y.J. Chang, Y.C. Hseih, Y.T. Lin, Sensible heat and friction characteristics of plate fin-and-tube heat exchangers having plane fins. Int. J. Refrig. 19(4), 223–230 (1996)CrossRefGoogle Scholar
  15. 15.
    X. Ma, G. Ding, Y. Zhang, K. Wang, Airside heat transfer and friction characteristics for enhanced fin-and-tube heat exchanger with hydrophilic coating under wet conditions. Int. J. Refrig. 30, 1153–1167 (2007)CrossRefGoogle Scholar
  16. 16.
    R. Yun, Y. Kim, Y. Kim, Air side heat transfer characteristics of plate finned tube heat exchangers with slit fin configuration under wet conditions. Appl. Therm. Eng. 29, 3014–3020 (2009)CrossRefGoogle Scholar
  17. 17.
    H.J. Kang, W. Li, H.Z. Li, R.C. Xim, W.Q. Tao, Experimental study on heat transfer and pressure drop characteristics of four types of plate fin-and-tube heat exchanger surfaces. J. Therm. Sci. 3(1), 34–42 (1994)CrossRefGoogle Scholar
  18. 18.
    J. Yin, Z. He, F. Chen, J. Ma, Effect of tube location change on heat transfer characteristics of plain plate fin-and-tube heat exchangers. J. Therm. Sci. Eng. Appl. 6(021005), 1–9 (2014)Google Scholar
  19. 19.
    M.A. González Hernández, A.I. López, A.A. Jarzabek, J.M. Perales Perales, Y. Wu, S. Xiaoxiao, Chapter 1: design methodology for a quick and low-cost wind tunnel, in Wind tunnel designs and their diverse engineering applications, ed by N.A. Ahmed (InTech Publisher, 2013)Google Scholar
  20. 20.
    S. Brusca, R. Lanzafame, M. Messina, Chapter 7: low-speed wind tunnel: design and build, in wind tunnel aerodynamics, models and experiments, in Wind tunnels: aerodynamics, models and experiments, ed. by J. Pereira (Nova Science Publications Inc., New York, 2011)Google Scholar
  21. 21.
    J.B. Barlow, W.H. Rae, A. Pope, Low-Speed Wind Tunnel Testing, 3rd edn. (Wiley, London, 1999)Google Scholar
  22. 22.
    G. Biswas, K. Torii, D. Fuji, K. Nishino, Numerical and experimental determination of flow structure and heat transfer effects of longitudinal vortices in a channel flow. Int. J. Heat Mass Transf. 39(16), 3441–3451 (1996)CrossRefGoogle Scholar
  23. 23.
    H.T. Chen, J.R. Lai, Study of heat-transfer characteristics on the fin of two-row plate finned-tube heat exchangers. Int. J. Heat Mass Transf. 55, 4088–4095 (2012)CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.Centre for Solar Energy TechnologyIndian Institute of Technology JodhpurJodhpurIndia
  2. 2.Department of Mechanical Engineering and Center for Solar EnergyIndian Institute of Technology JodhpurJodhpurIndia

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