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Heat and Mass Transfer

, Volume 52, Issue 3, pp 469–481 | Cite as

Influence of fluid temperature gradient on the flow within the shaft gap of a PLR pump

  • W. Qian
  • B. Rosic
  • Q. Zhang
  • B. Khanal
Original

Abstract

In nuclear power plants the primary-loop recirculation (PLR) pump circulates the high temperature/high-pressure coolant in order to remove the thermal energy generated within the reactor. The pump is sealed using the cold purge flow in the shaft seal gap between the rotating shaft and stationary casing, where different forms of Taylor–Couette flow instabilities develop. Due to the temperature difference between the hot recirculating water and the cold purge water (of order of 200 °C), the flow instabilities in the gap cause temperature fluctuations, which can lead to shaft or casing thermal fatigue cracks. The present work numerically investigated the influence of temperature difference and rotating speed on the structure and dynamics of the Taylor–Couette flow instabilities. The CFD solver used in this study was extensively validated against the experimental data published in the open literature. Influence of temperature difference on the fluid dynamics of Taylor vortices was investigated in this study. With large temperature difference, the structure of the Taylor vortices is greatly stretched at the interface region between the annulus gap and the lower recirculating cavity. Higher temperature difference and rotating speed induce lower fluctuating frequency and smaller circumferential wave number of Taylor vortices. However, the azimuthal wave speed remains unchanged with all the cases tested. The predicted axial location of the maximum temperature fluctuation on the shaft is in a good agreement with the experimental data, identifying the region potentially affected by the thermal fatigue. The physical understandings of such flow instabilities presented in this paper would be useful for future PLR pump design optimization.

Keywords

Couette Flow Thermal Fatigue Axial Flow Radius Ratio Taylor Number 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols

H

Annulus gap height (m)

h

Average heat transfer coefficient in the inner cylinder surface [W/(m2K)]

λ

Axial wavelength

s

Azimuthal wave speed

Tac

Critical Taylor number

f

Fundamental frequency of the azimuthal waves (Hz)

d

Gap width = R2 − R1(m)

Z

Height from the end of the annulus gap (m)

TH

Highest temperature (K)

Vin

Inlet velocity (m/s)

ν

Kinematic viscosity (m2/s)

keq

Local mean equivalent conductivity

TL

Lowest temperature (K)

m

Number of azimuthal waves

τ

Period time (s)

r

Radial coordinate (m)

R1

Radius of inner cylinder (m)

R2

Radius of outer cylinder (m)

η

Radius ratio = R1/R2

Ω1

Rotating speed of the inner cylinder (rad/s)

Ω2

Rotating speed of the outer cylinder (rad/s)

Re

Reynolds number

Ta

Taylor number which is defined as \(\frac{{\varOmega dR_{1} }}{\nu }\)

k

Thermal conductivity

Vz

Z-direction velocity (m/s)

References

  1. 1.
    Koschmieder EL (1993) Bénard cells and Taylor vortices. Cambridge University Press, CambridgezbMATHGoogle Scholar
  2. 2.
    Taylor GI (1923) Stability of a viscous liquid contained between two rotating cylinders. Philos Trans R Soc Lond A 223:289–343CrossRefzbMATHGoogle Scholar
  3. 3.
    Andereck CD, Liu SS, Swinney HL (1986) Flow regimes in a circular Couette system with independently rotating cylinders. J Fluid Mech 164(3):155–183CrossRefGoogle Scholar
  4. 4.
    Sparrow EM, Munro WD, Jonsson VK (1964) Instability of the flow between rotating cylinders: the wide gap problem. J Fluid Mech 20(1):35–46CrossRefMathSciNetzbMATHGoogle Scholar
  5. 5.
    Roberts PH (1965) The solution of the characteristic value problem. Proc R Soc Lond Ser A 283:550–556Google Scholar
  6. 6.
    Cognet G (1984) Les étapes vers la turbulence dans l’écoulement de Couette-Taylor entre cylindres coaxiaux. Journal de mécanique théorique et appliquée pp 7–44Google Scholar
  7. 7.
    Burkhalter JE, Koschmieder EL (1974) Steady supercritical Taylor vortices after sudden starts. Phys Fluids 17:1929–1935CrossRefGoogle Scholar
  8. 8.
    Kingt GP (1984) Wave speeds in wavy Taylor-vortex flow. J Fluid Mech 141:365–390CrossRefGoogle Scholar
  9. 9.
    Wereley ST, Lueptow RM (1999) Velocity field for Taylor–Couette flow with an axial flow. Phys Fluids 11:3637–3649CrossRefzbMATHGoogle Scholar
  10. 10.
    Becker KM, Kaye J (1962) The influence of a radial temperature gradient on the instability of fluid flow in an annulus with an inner rotating cylinder. J Heat Transfer 84:106–110CrossRefGoogle Scholar
  11. 11.
    Martin BW, Hasoon MA (1976) The stability of viscous axial flow in the entry region of an annulus with a rotating inner cylinder. J Mech Eng Sci 18(5):221–228CrossRefGoogle Scholar
  12. 12.
    Narabayashi T, Miyano H, Komita H, Iikura T, Shiina K, Kato H (1993) Study on temperature fluctuation mechanisms in an annulus gap between PLR pump shaft and casing cover. In: The 2nd ASME-JSME nuclear engineering joint conference, San Francisco, CA, pp 207–213Google Scholar
  13. 13.
    Kato H, Kanno H, Hosokawa M, Watanabe A, Shitara C, Ashizawa K (1992) Development of advanced nuclear primary loop recirculating pump (PLR pump) for BWR plant considering thermal fatigue problem. In: Winter annual meeting of the American society of mechanical engineers, Anaheim, CA, pp 157–162Google Scholar
  14. 14.
    Watanabe A, Takahashi Y, Igi T, Miyano H, Narabayashi T, Ikura T, Sagawa W, Hayashi M, Endo A, Kato H, Kanno H, Hosokawa M (1993) The study of thermal fatigue problem on reactor recirculation pump of BWR plant. Elsevier Sci. Pr. B.V., pp 383–388Google Scholar
  15. 15.
    Gazley C (1958) Heat transfer characteristics of the rotational and axial flow between concentric cylinders. J Heat Transfer 80(1):79–90Google Scholar
  16. 16.
    Tachibana F, Fukui S (1964) Convective heat transfer of the rotational and axial flow between two concentric cylinders. Bull JSME 7(26):385–391CrossRefGoogle Scholar
  17. 17.
    Aoki H, Nohira H, Arai H (1967) Convective heat transfer in an annulus with an inner rotating cylinder. Bull JSME 10(39):523–532CrossRefGoogle Scholar
  18. 18.
    Shiina K, Nakamura S, Mizushina Y, Yanagida T, Endo A, Takehara H, Kato H (1996) Heat transfer characteristics of fluid flow in an annulus with an inner rotating cylinder having a labyrinth structure. Heat Transfer-Jpn Res 25(2):103–119CrossRefGoogle Scholar
  19. 19.
    Fenot M, Bertin Y, Dorignac E, Lalizel G (2011) A review of heat transfer between concentric rotating cylinders with or without axial flow. Int J Therm Sci 50(7):1138–1155CrossRefGoogle Scholar
  20. 20.
    Liu D, Kang IS, Cha JE, Kim HB (2011) Experimental study on radial temperature gradient effect of a Taylor–Couette flow with axial wall slits. Exp Thermal Fluid Sci 35(7):1282–1292CrossRefGoogle Scholar
  21. 21.
    Ball KS, Farouk B, Dixit VC (1989) An experimental study of heat transfer in a vertical annulus with a rotating inner cylinder. Int J Heat Mass Transf 32(8):1517–1527CrossRefGoogle Scholar
  22. 22.
    Kedia R (1997) An investigation of velocity and temperature fields in Taylor–Couette flows. Dissertation (Ph.D.), California Institute of TechnologyGoogle Scholar
  23. 23.
    Cengel YA, Boles MA (2011) Thermodynamics: an engineering approach, vol 5. McGraw-Hill, New YorkGoogle Scholar
  24. 24.
    Di Prima RC, Swinney HL (1985) Instabilities and transition in flow between concentric rotating cylinders. Hydrodynamic instabilities and the transition to turbulence. Springer, Berlin, pp 139–180Google Scholar
  25. 25.
    Kaye J, Elgar EC (1957) Modes of adiabatic and diabatic fluid flow in an annulus with an inner rotating cylinder. MIT Research Laboratory of Heat Transfer in ElectronicsGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.University of Michigan-Shanghai Jiao Tong University Joint InstituteShanghai Jiao Tong UniversityShanghaiChina
  2. 2.Osney Thermo-Fluids Laboratory, Department of Engineering ScienceUniversity of OxfordOxfordUK
  3. 3.Department of Mechanical Engineering and Aeronautics, School of Mathematics, Computer Science & Engineering (MCSE)City University LondonLondonUK
  4. 4.Cranfield UniversityShrivenhamUK

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