Skip to main content
SpringerLink
Log in

Falling film evaporation of aqueous lithium bromide solution at low pressure

  • Original
  • Published:
Heat and Mass Transfer Aims and scope Submit manuscript

Abstract

Horizontal tube bundles are often used as falling film evaporators in absorption chillers, especially for systems working at low pressure with H2O/LiBr. The heat and mass transfer processes in these apparatuses are affected by several physical effects and the geometrical design of the heat exchanger, for example the material properties of the working fluid or the surface structure of the heat exchanger. Several influencing parameters are summarized and evaluated. Correlations for the prediction of the heat transfer coefficients of falling film evaporators from the literature are discussed concerning their applicability in dependence of the working conditions of the evaporator in an absorption chiller. In this work, experimental investigations are carried out in a falling film evaporator consisting of a horizontal tube bundle with eighty horizontal tubes installed in an absorption chiller because of a lack of consistent data for heat and mass transfer in the literature. The heat and mass transfer mechanisms and the flow pattern in the falling film are analysed and compared with correlations from literature. The deviations of the experimental data from those of the correlations are within a tolerance of 30%. These deviations may be explained by a change of the flow pattern at a lower Reynolds number than compared to the literature.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11

Similar content being viewed by others

Abbreviations

A:

Area (m2)

a:

Thermal diffusivity (m2/s)

cp :

Isobaric specific heat capacity (kJ/kgK)

d:

Tube Diameter (m)

D* :

Dimensionless diameter (−)

g:

Acceleration of gravity (m/s2)

h:

Specific enthalpy (J/kg)

j:

Number (−)

k:

Overall heat transfer coefficient (W/m2K)

l:

Length (m)

\( \dot{\mathrm{m}} \) :

Mass flux (kg/s)

p:

Pressure (mbar)

\( \dot{\mathrm{Q}} \) :

Heat flux (W)

\( \dot{\mathrm{q}} \) :

Heat flux density (W/m2)

s:

Inter-tube spacing (m)

T:

Temperature (K)

x:

Mass related concentration (mass fraction kgLiBr/kgsolution) (%)

Ar:

Archimedes number

Ga:

Galilei number

Nu:

Nusselt number

Pr:

Prandtl number

Re:

Reynolds number

Ref :

Film Reynolds number

Sc:

Schmidt number

α:

Heat transfer coefficient (W/m2K)

\( \dot{\Gamma} \) :

Mass flow per unit length (kg/ms)

η:

Dynamic viscosity (Pas)

λ:

Thermal conductivity (W/mK)

ν:

Kinematic viscosity (m2/s)

ξ:

Friction factor (−)

ρ:

Density (kg/m3)

σ:

Surface tension (N/m)

cu:

Copper

f:

Film

h:

Hot water

i:

Inlet / inner

lat:

Latent

O:

Outer/outlet

s:

Solution

sat:

Saturation

sens:

Sensible

sys:

systemic

v:

Vaporization

w:

Wall

eq:

Equilibrium

References

  1. Gluesenkamp K, Radermacher R, Hwang Y (2011) Trends in absorption machines, Proceedings of the International Sorption Heat Pump Conference, Padua, Italy, April 5-7, 2011

  2. Jeong S, Garimella S (2005) Optimal design of compact horizontal tube LiBr/water absorbers. HVAC&R Research 11(1):27–44

    Article  Google Scholar 

  3. Sernas V (1979) Heat transfer correlation for subcooled water films on horizontal tubes. J Heat Transf 101

  4. Hu X, Jacobi AM (1996) The Intertube falling film: part 2 – mode effects on sensible heat transfer to a falling liquid film. J Heat Trans T ASME 118:626–633

    Article  Google Scholar 

  5. Jani S (2012) Simulation of heat and mass transfer process in falling film single tube absorption gernerator. International Journal of Science and Engineering Investigations (IJSEI) 1(3):79–84

    Google Scholar 

  6. Ribatski G, Jacobi AM (2005) Falling-film evaporation on horizontal tubes – a critical review. Int J Refrig 28:635–653

    Article  Google Scholar 

  7. Mitrovic J (2005) Flow structures of a liquid falling film on horizontal tubes. Chem Eng Technol 28(No. 6)

  8. Mitrovic J (1990) Wärmeübergang in Rieselfilmen an waagrechten Rohren. In: Fortschritt-Berichte VDI / Reihe 3; 211; VDI Verlag

  9. Roques JF, Dupont V, Thome JR (2002) Falling film transitions on plain and enhanced tubes. ASME J Heat Transf 124(3):491–499

    Article  Google Scholar 

  10. Hu X, Jacobi AM (1996) The intertube falling film: part 1—flow characteristics, mode transitions, and hysteresis. J Heat Trans T ASME 118:616–625

    Article  Google Scholar 

  11. Chyu, Bergles (1987) An analytical and experimental study of falling-film evaporation on a horizontal tube. J Heat Trans T ASME 109:983–990

    Article  Google Scholar 

  12. Habert M (2009) Falling film evaporation on a tube bundle with plain and enhanced tubes. “Dissertation”, Ecole Polytechnique Federale de Lausanne

  13. Tomforde C, Luke A (2014) Influence of microstructured surface modifications on the wettability of absorber tubes, Proceedings of the International Sorption Heat Pump Conference, College Park, Maryland, USA, 30 March – 2 April 2014

  14. Lorenz JJ, Yung D (1979) A node on Combindes boiling and evaporation of liquid films on horizontal tubes. J Heat trans T ASME 101:178

    Article  Google Scholar 

  15. Fujita Y, Tsutsui M (1995) Evaporation heat transfer of falling films on horizontal tube. Part 2. Experimental study. Heat Tran Jpn Res 24:17–31

    Google Scholar 

  16. Fujita Y, Tsutsui M (1998) Experimental investigation of falling film evaporation on horizontal tubes. Heat Tran Jpn Res 27:609–618

    Article  Google Scholar 

  17. Owens WL (1978) Correlation of thin film evaporation heat transfer coefficient of horizontal tubes. Proc. 5th OTEC Conference

  18. Yang L, Shen S (2008) Experimental study of falling film evaporation heat transfer outside horizontal tubes. Desalination 220:654–660

    Article  Google Scholar 

  19. Mitrovic J (1986) Influence of tube spacing and flow rate on heat transfer from a horizontal tube to a falling liquid film. Proceedings of the Eighth International Heat Transfer Conference, San Francisco 4:1949–1956

    Google Scholar 

  20. Parken WH (1975) Heat transfer to thin films on horizontal tubes, PhD Thesis, Rutgers University

  21. Armbruster R, Mitrovic J (1995) Heat transfer in falling film on a horizontal tube, Proceedings of the national heat transfer conference, Portland, vol. 12 [ASME HTD-vol. 314], p 13–21

  22. Parken WH, Fletcher LS, Sernas V, Han JC (1990) Heat transfer trough falling film evaporation and boiling on horizontal tubes. J Heat Transf 112:744–750

    Article  Google Scholar 

  23. Olbricht M, Luke A (2014) Investigation of the operation conditions of an absorption cycle with compact heat exchangers, International Sorption Heat Pump Conference March 31- April 3 2014 Washington

  24. Olbricht M, Luke A (2015) Prediction an experimental investigation of heat and mass transfer charactersitics of a horizontal tube bundle absorber, International Congress of Refrigeration, Yokohama

  25. Patek J, Klomfar J (2006) A computationally effective formulation of the thermodynamic properties of LiBr-H2O from 273 to 500 K over full composition range. Int J Refrig 29:566–578

    Article  Google Scholar 

  26. Gnielinski V (1976) New equations for heat and mass transfer in turbulent pipe and channel flow. Int Chem Eng 16:359–368

    Google Scholar 

  27. Serth WR (2012) Process heat transfer – principles and applications. Elsevier, 2007, p 79-84

  28. DiGuilio RM, Lee RJ, Jeter SM, Teja AS (1990) Properties of lithium bromide-water solutions at high temperatures and concentrations - I thermal conductivity; ASHRAE Transactions, Paper 3380, RP-527, p 702–708

  29. Lee RJ, DiGuilio RM, Jeter SM, Teja AS (1990) Properties of lithium bromide-water solutions at high temperatures and concentrations - II density and viscosity; ASHRAE Transactions, Paper 3381, RP-527, p 709-714

  30. Löwer H (1960) Thermodynamische und physikalische Eigenschaften der wässrigen Lithiumbromid-Lösung, Dissertation Technische Hochschule Karlsruhe

  31. Gierow M, Jernqvist A (1993) Measurement of Mass Diffusivity with Holographic Interferometry for H2O/NaOH and H2O/LiBr Workig Pairs; Proceedings of the International Absorption Heat Pump Conference

  32. DIN Deutsches Institut für Normung e.V. (1999) DIN V ENV 13005 Leitfaden zur Angabe der Unsicherheit beim Messen; Beuth Verlag Berlin

  33. Olbricht M (2017) Einfluss des Wärme- und Stofftransports im thermischen Verdichter auf das Systemverhalten von Absorptionskältemaschinen, Ph. D. Thesis, University of Kassel

  34. Ziegler F, Albers J, Lanser W, Petersen S (2013) EnEff Wärme: Absorptionskältetechnik für Niedertemperaturantreib – Grundlagen und Entwicklung von Absorptionskältemaschinen für die fernwärme- und solarbasierte Kälteversorgung; Final Report BMWi Project 0327460B; Berlin

Download references

Acknowledgements

A part of this data was presented at the 7th European Thermal-Sciences Conference (Eurotherm 2016) from 19 to 23 June 2016 in Krakow, Poland.

Author information

Authors and Affiliations

  1. Institute of Technical Thermodynamics, University of Kassel, Kurt-Wolters-Straße 3, 34125, Kassel, Germany

    Michael Olbricht & Andrea Luke

Authors
  1. Michael Olbricht
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Andrea Luke
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Michael Olbricht.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Olbricht, M., Luke, A. Falling film evaporation of aqueous lithium bromide solution at low pressure. Heat Mass Transfer 54, 2507–2520 (2018). https://doi.org/10.1007/s00231-018-2409-0

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00231-018-2409-0

Search

Navigation