Skip to main content
SpringerLink
Log in

Heat transfer and pressure drop of R-134a condensation in a coiled, double tube

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

Abstract

An experimental study was carried out to investigate condensation heat transfer and pressure drop characteristics of R-134a in a coiled double tube oriented with its helix axis in the vertical direction. Measurements were obtained at inlet pressure of 815 kPa for refrigerant mass flux ranging from 95 to 710 kg/m2s and cooling water Reynolds number varying from 1000 to 14000. Presented results illustrate the effects of refrigerant mass flux and average condensation temperature difference on the condensation heat transfer coefficient and pressure drop. Comparison with relevant data from other sources indicates a reasonable agreement. An empirical correlation was obtained for predicting condensation heat transfer coefficient. The present study may be considered of a practical and theoretical interest for the design of the helical double-tube condensers using R-134a as the working fluid.

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

Similar content being viewed by others

Abbreviations

CFC:

Chlorofluorocarbon

HCFC:

Hydro chlorofluorocarbon

HTC:

Heat transfer coefficient

A :

Heat transfer surface area (m2)

Cp :

Specific heat at constant pressure (J/kg °C)

d o :

Outer diameter of inner coil tube (m)

d i :

Inside diameter of external coil tube (m)

d c :

Coil diameter (m)

Dew:

Waterside Dean number Re w [(d i − d o)/d c]0.5

h fg :

Condensation latent heat (J/kg)

k :

Thermal conductivity (W/m °C)

\( \dot{M} \) :

Mass flux (kg/m2s)

\( \dot{m}_{\text{cw}} \) :

Cooling water mass flow rate (kg/s)

Nu :

Nusselt number αd/k

p :

Pressure (kPa)

Pr :

Prandtl number Cpμ/k

\( \dot{Q}_{\text{L}} \) :

Condensation load (W) \( \dot{M}_{\text{r}} h_{fg} \)

\( \dot{Q}_{\text{cw}} \) :

Heat rate absorbed by cooling water (W), defined by Eq. 1

R t :

Thermal resistance of inner tube wall (m2 °C/W)

\( \mathop{Re}\limits^{*}{\!_{{\text{rr}}}} \) :

Refrigerant Reynolds number, cf., Eq. 6

Re w :

Water Reynolds number \( \dot{M}_{\text{w}} (d_{\text{o}} - d_{\text{i}} )/\mu_{\text{w}} \)

T :

Temperature (°C)

T s :

Refrigerant saturation temperature (°C)

T cw :

Average cooling water temperature (°C) (T cwi + T cwo)/2

x m :

Mean vapour quality

α:

Heat transfer coefficient (W/m2°C)

μ:

Dynamic viscosity (kg/m s)

ρ:

Density (kg/m3)

ΔP :

Refrigerant pressure drop across the test section (kPa/m)

ΔT s :

Average vapour-to-water temperature difference (°C) (T s − T cw)

ΔT m :

Logarithmic mean temperature difference (°C), defined by Eq. 3

c:

Condensation

w:

Water

cwi:

Inlet cooling water

cwo:

Outlet cooling water

i:

Inlet or inner

l:

Liquid

o:

Outlet/overall

s:

Saturation

r:

Refrigerant

v:

Vapour

References

  1. Copenhagen Amendments to Montreal Protocol, 25 Nov 1992

  2. Yan Y-Y, Lin T-F (1999) Condensation heat transfer and pressure drop of refrigerant R-134a in a small pipe. Int J Heat Mass Transf 42:697–708

    Article  MathSciNet  Google Scholar 

  3. Coleman JW, Garimella S (2003) Two-phase flow regimes in round, square and rectangular tubes during condensation of refrigerant R-134a. Int J Refrig 26:117–128

    Article  Google Scholar 

  4. Jung D, Song K, Cho Y, Kim S (1972) Flow condensation heat transfer coefficients of pure refrigerants. Int J Refrig 26:4–11

    Article  Google Scholar 

  5. Samuel MS, Maltais H (2000) Experimental investigations of two phase flow condensation inside enhanced surface tubing. Appl Therm Eng 20:1113–1126

    Article  Google Scholar 

  6. Liu X (1997) Condensing and evaporating heat transfer and pressure drop characteristics of HCF-134a and HCF-22. ASME J Heat Transf 119:158–163

    Article  Google Scholar 

  7. Nualboornueng T (2004) Two-phase condensation heat transfer coefficients of HFC-134a in smooth and micro-fin tubes at high mass flux. Int Commun Heat Mass Transf 31:991–1004

    Article  Google Scholar 

  8. Nualboornueng T, Wongwises S (2003) Two-phase flow pressure drop of HFC-134a during condensation at high mass flux in smooth and micro-fin tubes. Int Commun Heat Mass Transf 30:577–590

    Article  Google Scholar 

  9. Kumar R, Gupta A, Vishvakarma S (2005) Condensation of R-134a vapour over single horizontal integral-fin tubes: effect of fin height. Int J Refrig 28:428–435

    Article  Google Scholar 

  10. Rennie JT, Raghavan GSV (2005) Experimental studies of a double-pipe helical heat exchanger. Exp Therm Fluid Sci J 29:919–924

    Article  Google Scholar 

  11. Uddin M, Patrik J, Newlin A (1994) Variation of local condensation heat transfer for R-134a in helically coiled tubes. In: International mechanical engineering congress and exhibition, Winter Annular Meeting, Chicago, pp 6–11

  12. Kang HJ, Lin CX, Ebadian MA (2000) Condensation of R-134a flowing inside helical pipes. Int J Heat Mass Transf 43:2553–2564

    Article  Google Scholar 

  13. Han JT, Lin CX, Ebadian MA (2000) Experimental investigation of condensation heat transfer of refrigerant R-134a in helicoidal pipe. In: Proceeding of ASME heat transfer division, HTD-4, pp 95–101

  14. Yu B, Han JT, Kang HJ, Lin CX, Awwad A, Ebadian MA (2003) Condensation heat transfer of R-134a flow inside helical pipes at different orientations. Int Commun Heat Mass Transf 30:745–754

    Article  Google Scholar 

  15. Wongwises S, Polsongkram M (2006) Condensation heat transfer and pressure drop of HFC-134a in a helically coiled concentric tube-in-tube heat exchanger. Int J Heat Mass Transf 49:4386–4398

    Article  MATH  Google Scholar 

  16. Garimella S, Richerds DE, Christensen RN (1998) Experimental investigation of heat transfer in coiled annular ducts. ASME J Heat Transf 110:329–336

    Article  Google Scholar 

  17. Gnielinski V (1986) Heat transfer and pressure drop in helically coiled tubes. In: Proceeding of international meeting on reactor heat transfer, Karlsruhe, pp 351–372

  18. Moffat RJ (1988) Describing uncertainties in experimental results. Exp Therm Fluid Sci J 1:3–7

    Article  Google Scholar 

  19. Cavallini A, Del Col D, Doretti L, Longo GA, Ressetto L (2000) Heat transfer and pressure drop during condensation of refrigerants inside horizontal enhanced tubes. Int J Refrig 23:4–25

    Article  Google Scholar 

  20. Longo GA, Gasparella A, Sartori R (2004) Experimental heat transfer coefficients during refrigerant condensation inside herringbone-type plate heat exchangers with enhanced surfaces. Int J Heat Mass Transf 47:4125–4136

    Article  Google Scholar 

  21. Honda H, Takata N, Takamatsu H, Kim JS, Usami K (2002) Condensation of downward-flowing HFC134a in a staggered bundle of horizontal finned tubes. Int J Refrig 25:3–10

    Article  Google Scholar 

  22. Cavallini A, Censi G, Del Col D, Doretti L, Longo GA, Ressetto L (2001) Experimental investigation on condensation heat transfer and pressure drop of new HFC refrigerants (R134a, R125, R32, R410A, R236ea). Int J Refrig 24:73–87

    Article  Google Scholar 

  23. Zaki M, Liu YZ, Dong ZF, Ebadian MA (1997) Condensation heat transfer of R-134a in helical pipes. In: Proceeding of ASME heat transfer division, HTD-351, pp 141–148

Download references

Acknowledgments

This work was supported by the Public Authority for Applied Education and Training (PAAET) of Kuwait through a research grant number: Ts 03-06. This financial support is greatly appreciated.

Author information

Authors and Affiliations

  1. Mechanical Power and Refrigeration Department, Faculty of Technological Studies, P.O. Box 64268, 7045, Shuwaikh, Kuwait

    M. El-Sayed Mosaad, M. Al-Hajeri, R. Al-Ajmi & Abo. M. Koliub

Authors
  1. M. El-Sayed Mosaad
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. M. Al-Hajeri
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. R. Al-Ajmi
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Abo. M. Koliub
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to M. El-Sayed Mosaad.

Additional information

M. El-Sayed Mosaad is on leave from Mechanical Engineering Department, Mansoura University, Egypt.

Rights and permissions

Reprints and permissions

About this article

Cite this article

El-Sayed Mosaad, M., Al-Hajeri, M., Al-Ajmi, R. et al. Heat transfer and pressure drop of R-134a condensation in a coiled, double tube. Heat Mass Transfer 45, 1107–1115 (2009). https://doi.org/10.1007/s00231-009-0484-y

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00231-009-0484-y

Keywords

Search

Navigation