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Research Papers

Numerical and Experimental Research on the Fluid-Induced Forces of Clearance Flow in Canned Motor Reactor Coolant Pump

[+] Author and Article Information
Rui Xu

School of Mechanical Engineering,
Shanghai Jiao Tong University,
Shanghai 200240, China
e-mail: sharry0727@sjtu.edu.cn

Yun Long

Research Center of Fluid Machinery Engineering
and Technology,
Jiangsu University,
Jiangsu 212013, China
e-mail: longyunjs@outlook.com

Yaoyu Hu

School of Mechanical Engineering,
Shanghai Jiao Tong University,
Shanghai 200240, China
e-mail: huyaoyu@sjtu.edu.cn

Junlian Yin

School of Mechanical Engineering,
Shanghai Jiao Tong University,
Shanghai 200240, China
e-mail: jlyin@sjtu.edu.cn

Dezhong Wang

School of Mechanical Engineering,
Shanghai Jiao Tong University,
Shanghai 200240, China
e-mail: dzwang@sjtu.edu.cn

1Corresponding authors.

Manuscript received April 15, 2018; final manuscript received October 15, 2018; published online April 15, 2019. Assoc. Editor: Haixin Chen.

J. Eng. Gas Turbines Power 141(6), 061021 (Apr 15, 2019) (7 pages) Paper No: GTP-18-1168; doi: 10.1115/1.4041756 History: Received April 15, 2018; Revised October 15, 2018

Reactor coolant pump (RCP) is one of the most important equipment of the coolant loop in a pressurized water reactor system. Its safety relies on the characteristics of the rotordynamic system. For a canned motor RCP, the liquid coolant fills up the clearance between the metal shields of the rotor and stator inside the canned motor, forming a long clearance flow. The fluid-induced forces of the clearance flow in canned motor RCP and their effects on the rotordynamic characteristics of the pump are numerically and experimentally analyzed in this work. A transient computational fluid dynamics (CFD) method has been used to investigate the fluid-induced force of the clearance. A vertical experiment rig has also been established for the purpose of measuring the fluid-induced forces. Fluid-induced forces of clearance flow with various whirl frequencies and various boundary conditions are obtained through the CFD method and the experiment. Results show that clearance flow brings large mass coefficient into the rotordynamic system and the direct stiffness coefficient is negative under the normal operating condition. The rotordynamic stability of canned motor RCP does not deteriorate despite the existence of significant cross-coupled stiffness coefficient from the fluid-induced forces of the clearance flow.

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References

De, C. , Zhen-Qiang, Y. , Ya-Bo, X. , and Hong, S. , 2014, “ Numerical Study on Seismic Response of the Reactor Coolant Pump in Advanced Passive Pressurized Water Reactor,” Nucl. Eng. Des., 278, pp. 39–49. [CrossRef]
Fritz, R. J. , 1970, “ The Effects of an Annular Fluid on the Vibrations of a Long Rotor—Part 1: Theory,” J. Basic Eng., 92(4), pp. 923–929. [CrossRef]
Fritz, R. J. , 1970, “ The Effects of an Annular Fluid on the Vibrations of a Long Rotor—Part 2: Test,” ASME J. Basic Eng., 92(4), pp. 930–937. [CrossRef]
Childs, D. W. , 1983, “ Dynamic Analysis of Turbulent Annular Seals Based on Hirs' Lubrication Equation,” J. Lubr. Technol., 105(3), pp. 429–436. [CrossRef]
Childs, D. W. , Mclean, J. E. , Jr., Zhang, M. , and Arthur, S. P. , 2016, “ Rotordynamic Performance of a Negative-Swirl Brake for a Tooth-on-Stator Labyrinth Seal,” ASME J. Eng. Gas Turbines Power, 138(6), p. 062505. [CrossRef]
Iwatsubo, T. , 1980, “ Evaluation of Instability Forces of Labyrinth Seals in Turbines or Compressors,” Rotordynamic Instability Problems in High Performance Turbomachinery, NASA CP-2133, Texas A&M University, College Station, TX, pp. 139–167.
Iwatsubo, T. , and Ishimaru, H. , 2010, “ Consideration of Whirl Frequency Ratio and Effective Damping Coefficient of Seal,” J. Syst. Des. Dyn., 4(1), pp. 177–188.
Kanemori, Y. , and Iwatsubo, T. , 1989, “ Experimental Study of Dynamical Characteristics of a Long Annular Seal (In the Case of Concentric Rotor and Outer Cylinder),” JSME Int. J. Ser. 2, 32(2), pp. 218–224.
Kanemori, Y. , and Iwatsubo, T. , 1994, “ Rotordynamic Analysis of Submerged Motor Pumps: Influence of Long Seal on the Stability of Fluid Machinery,” JSME Int. J. Ser. C, 37(1), pp. 193–201.
Antunes, J. , Axisa, F. , and Grunenwald, T. , 1996, “ Dynamics of Rotors Immersed in Eccentric Annular Flow—Part 1: Theory,” J. Fluids Struct., 10(8), pp. 893–918. [CrossRef]
Grunenwald, T. , Axisa, F. , Bennett, G. , and Antunesc, J. , 1996, “ Dynamics of Rotors Immersed in Eccentric Annular Flow—Part 2: Experiments,” J. Fluids Struct., 10(8), pp. 919–944. [CrossRef]
Dietzen, F. J. , and Nordmann, R. , 1987, “ Calculating Rotordynamic Coefficients of Seals by Finite Difference Techniques,” ASME J. Tribol., 109(3), pp. 388–394. [CrossRef]
Rhode, D. L. , Hensel, S. J. , and Guidry, M. J. , 1992, “ Labyrinth Seal Rotordynamic Forces Using a Three-Dimensional Navier-Stokes Code,” ASME J. Tribol., 114(4), pp. 683–689. [CrossRef]
Arghir, M. , and Frêne, J. , 1999, “ A Quasi-Two-Dimensional Method for the Rotordynamic Analysis of Centered Labyrinth Liquid Seals,” ASME J. Eng. Gas Turbines Power, 121(1), pp. 144–152. [CrossRef]
Athavale, M. , and Przekwas, A. , 1994, “ SCISEAL: A CFD Code for Analysis of Fluid Dynamic Forces in Seals,” NASA Workshop on Seals and Flow Code Development-1993, NASA CP-10136.
Moore, J. J. , and Palazzolo, A. B. , 1999, “ Rotordynamic Force Prediction of Whirling Centrifugal Impeller Shroud Passages Using Computational Fluid Dynamic Techniques,” ASME International Gas Turbine and Aeroengine Congress and Exposition, Indianapolis, IN, June 9–12.
Moore, J. J. , Ransom, D. L. , and Viana, F. , 2010, “ Rotordynamic Force Prediction of Centrifugal Compressor Impellers Using Computational Fluid Dynamics,” ASME J. Eng. Gas Turbines Power, 133(4), p. 042504. [CrossRef]
Subramanian, S. , Sekhar, A. S. , and Prasad, B. V. S. S. S. , 2016, “ Rotordynamic Characteristics of Rotating Labyrinth Gas Turbine Seal With Centrifugal Growth,” Tribol. Int., 97, pp. 349–59. [CrossRef]
Chochua, G. , and Soulas, T. A. , 2006, “ Numerical Modeling of Rotordynamic Coefficients for Deliberately Roughened Stator Gas Annular Seals,” ASME J. Tribol., 129(2), pp. 424–429. [CrossRef]
Yan, X. , Li, J. , and Feng, Z. , 2011, “ Investigations on the Rotordynamic Characteristics of a Hole-Pattern Seal Using Transient CFD and Periodic Circular Orbit Model,” ASME J. Vib. Acoust., 133(4), p. 041007. [CrossRef]
Yan, X. , He, K. , Li, J. , and Feng, Z. , 2015, “ A Generalized Prediction Method for Rotordynamic Coefficients of Annular Gas Seals,” ASME J. Eng. Gas Turbines Power, 137(9), p. 092506. [CrossRef]
Wu, D. , Jiang, X. , Li, S. , and Wang, L. , 2016, “ A New Transient CFD Method for Determining the Dynamic Coefficients of Liquid Annular Seals,” J. Mech. Sci. Technol., 30(8), pp. 3477–3486. [CrossRef]
Untaroiu, A. , Untaroiu, C. D. , Wood, H. G. , and Allaire, P. E. , 2013, “ Numerical Modeling of Fluid-Induced Rotordynamic Forces in Seals With Large Aspect Ratios,” ASME J. Eng. Gas Turbines Power, 135(1), p. 012501. [CrossRef]
Untaroiu, A. , Hayrapetian, V. , Untaroiu, C. D. , Allaire, P. E. , Wood, H. G. , Schiavello, B. , and McGuire, J. , 2011, “ Fluid-Induced Forces in Pump Liquid Seals With Large Aspect Ratio,” ASME Paper No. AJK2011-06085.
Brown, P. D. , and Childs, D. W. , 2012, “ Measurement Versus Predictions of Rotordynamic Coefficients of a Hole-Pattern Gas Seal With Negative Preswirl,” ASME J. Eng. Gas Turbines Power, 134(12), p. 122503. [CrossRef]
Mehta, N. J. , and Childs, D. W. , 2014, “ Measured Comparison of Leakage and Rotordynamic Characteristics for a Slanted-Tooth and a Straight-Tooth Labyrinth Seal,” ASME J. Eng. Gas Turbines Power, 136(1), p. 012501. [CrossRef]
Kerr, B. G. , 2005, Experimental and Theoretical Rotordynamic Coefficients and Leakage of Straight Smooth Annular Gas Seals, M.S. thesis, Texas A&M University, College Station, TX.
Kirk, G. , and Gao, R. , 2012, “ Influence of Preswirl on Rotordynamic Characteristics of Labyrinth Seals,” Tribol. Trans., 55(3), pp. 357–364. [CrossRef]
Sun, D. , Wang, S. , Xiao, Z. , Meng, J. , Wang, X. , and Zheng, T. , 2015, “ Measurement Versus Predictions of Rotordynamic Coefficients of Seal With Swirl Brakes,” Mech. Mach. Theory, 94, pp. 188–99. [CrossRef]
Ertas, B. H. , Delgado, A. , and Vannini, G. , 2012, “ Rotordynamic Force Coefficients for Three Types of Annular Gas Seals With Inlet Preswirl and High Differential Pressure Ratio,” ASME J. Eng. Gas Turbines Power, 134(4), p. 042503. [CrossRef]
Jolly, P. , Hassini, A. , Arghir, M. , Bonneau, O. , and Guingo, S. , 2014, “ Experimental and Theoretical Rotordynamic Coefficients of Smooth and Round-Hole Pattern Water Fed Annular Seals,” ASME Paper No. GT2014-25677.
Kwanka, K. , 2007, “ Rotordynamic Coefficients of Short Labyrinth Gas Seals—General Dependency on Geometric and Physical Parameters,” Tribol. Trans., 50(4), pp. 558–563. [CrossRef]
Sreedharan, S. S. , Vannini, G. , and Mistry, H. , 2014, “ CFD Assessment of Rotordynamic Coefficients in Labyrinth Seals,” ASME Paper No. GT2014-26999.
Millsaps, K. T. , and Martinez-Sanchez, M. , 1994, “ Rotordynamic Forces in Labyrinth Seals: Theory and Experiment,” NASA Conference Publication 3239, Workshop held at Texas A&M University, College Station, TX, pp. 179–207.
Zhai, L. , Wu, G. , Wei, X. , and Qin, D. , 2015, “ Theoretical and Experimental Analysis for Leakage Rate and Dynamic Characteristics of Herringbone-Grooved Liquid Seals,” Proc. Inst. Mech. Eng., Part J, 229(7), pp. 849–60. [CrossRef]
ANSYS, 2013, “ ANSYS FLUENT 15.0 Theory Guide,” ANSYS, Cannonsberg, PA.
Hu, Y. , Wang, D. , Yin, J. , and Wang, Y. , 2014, “ Numerical Analysis of Rotordynamic Coefficients of Annular Flow in Canned Motor RCP,” ASME Paper No. ICONE22-30511.

Figures

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Fig. 1

Canned motor RCP [1]

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Fig. 2

Sketch of rotor, stator, and clearance flow in canned motor RCP: 1—impeller, 2—upper flywheel, 3—upper journal bearing, 4—rotor, 5—stator, 6—clearance, 7—lower journal bearing, 8—thrust bearing, 9—lower flywheel, 10—auxiliary impeller, and 11—inlet of clearance flow

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Fig. 3

Overview of the experiment rig

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Fig. 4

Power transmission schematic diagram of the experiment rig

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Fig. 5

One leg of the RFMC: 1—stationary bearing housing, 2—leg, 3—suspension lever, 4—crank, 5—roller bearings, 6—nut, 7—screw bolt, 8—dynamic force sensor, 9—screw bolt, 10—nuts, 11—vertical baffle, 12—base plate, and 13—pins

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Fig. 6

Radial force measurement components: 1—dynamic force sensors on the legs and 2—auxiliary dynamic force sensor

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Fig. 7

Fluid domain of the numerical and experimental study

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Fig. 8

Structured grid used in the numerical study

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Fig. 9

Cross section of clearance

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Fig. 10

G value of the transient CFD method and experiment

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Fig. 11

Fn and Ft of clearance flow in canned motor RCP, ωR = 188.5 rad/s

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