Research Papers: Hydrodynamic Lubrication

A Transient Thermoelastohydrodynamic Lubrication Model for the Slipper/Swashplate in Axial Piston Machines

[+] Author and Article Information
Andrew Schenk

Department of Agricultural and
Biological Engineering,
Purdue University,
225 S. University Street,
West Lafayette, IN 47907
e-mail: schenka@purdue.edu

Monika Ivantysynova

Department of Agricultural and
Biological Engineering,
Purdue University,
225 S. University Street,
West Lafayette, IN 47907
e-mail: mivantys@purdue.edu

Contributed by the Tribology Division of ASME for publication in the JOURNAL OF TRIBOLOGY. Manuscript received August 20, 2014; final manuscript received January 24, 2015; published online March 13, 2015. Assoc. Editor: Daniel Nélias.

J. Tribol 137(3), 031701 (Jul 01, 2015) (10 pages) Paper No: TRIB-14-1209; doi: 10.1115/1.4029674 History: Received August 20, 2014; Revised January 24, 2015; Online March 13, 2015

A transient lubrication model has been developed for the sliding interface between the slipper and swashplate in axial piston hydraulic pumps and motors. The model considers a nonisothermal fluid model, microdynamic motion of the slipper, as well as pressure and thermal deformations of the bounding solid bodies through a partitioned solution scheme. The separate contributions of elastohydrostatic and elastohydrodynamic lubrication are studied. Although hydrostatic deformation dominates, hydrodynamic effects are crucial for actual operation. Finally, the impact of transient deformation on lubricant pressure is explored, with its consideration necessary for accurate analysis.

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Schenk, A., and Ivantysynova, M., 2014, “A Transient Fluid Structure Interaction Model for Lubrication Between the Slipper and Swashplate in Axial Piston Machines,” The 9th International Fluid Power Conference, Mar. 24–26, Vol. 1, pp. 398–409.
Koc, E., Hooke, C., and Li, K., 1992, “Slipper Balance in Axial Piston Pumps and Motors,” ASME J. Tribol., 114(4), pp. 766–772. [CrossRef]
Koc, E., and Hooke, C., 1996, “Investigation into the Effects of Orifice Size, Offset and Overclamp Ratio on the Lubrication of Slipper Bearings,” Tribol. Int., 29(4), pp. 299–305. [CrossRef]
Kazama, T., and Yamaguchi, A., 1993, “Application of a Mixed Lubrication Model for Hydrostatic Thrust Bearings of Hydraulic Equipment,” ASME J. Tribol., 115(4), pp. 686–691. [CrossRef]
Bergada, J., Kumar, S., Davies, D. LI., and Watton, J., 2011, “A Complete Analysis of Axial Piston Pump Leakage and Output Flow Ripples,” Appl. Math. Model., 36(4), pp. 1731–1751. [CrossRef]
Bergada, J., Watton, J., Haynes, J., and Davies, D., 2010, “The Hydrostatic/Hydrodynamic Behavior of an Axial Piston Pump Slipper With Multiple Lands,” Meccanica, 45(4), pp. 585–602. [CrossRef]
Pelosi, M., and Ivantysynova, M., 2012, “Heat Transfer and Thermal Elastic Deformation Analysis on the Piston/Cylinder Interface of Axial Piston Machines,” ASME J. Tribol., 134(4), pp. 1–15. [CrossRef]
Zecchi, M., 2013, “A Novel Fluid Structure Interaction and Thermal Model to Predict the Cylinder Block/Valve Plate Interface Performance in Swash Plate Type Axial Piston Machines,” Ph.D. thesis, Purdue University, West Lafayette, IN.
Dhar, S., and Vacca, A., 2013, “A Fluid Structure Interaction-EHD Model of the Lubricating Gaps in External Gear Machines: Formulation and Validation,” Tribol. Int., 62, pp. 78–90. [CrossRef]
Ivantysyn, J., and Ivantysynova, M., 2001, Hydrostatic Pumps and Motors, Principles, Designs, Performance, Modeling, Analysis, Control, and Testing, Academic Books International, New Delhi, India.
Wieczorek, U., and Ivantysynova, M., 2000, “Caspar-A Computer-Aided Design Tool for Axial Piston Machines,” Bath Workshop on Power Transmission and Motion Control, University of Bath, Bath, UK, pp. 113–126.
Beschorner, K., Higgs, C., and Lovell, M., 2009, “Solution of Reynolds Equation in Polar Coordinates Applicable to Nonsymmetric Entrainment Velocities,” ASME J. Tribol., 131(3), p. 034501. [CrossRef]
Renard, Y., 2011, “Gmm++ User Documentation, Release 4.1.1.” Available at: http://download.gna.org/getfem/html/homepage/gmm.html
Kudish, I., 2002, “A Conformal Lubricated Contact of Cylinder Surfaces Involved in a Non-Steady Motion,” ASME J. Tribol., 124(1), pp. 62–71. [CrossRef]
Liu, G., and Quek, S., 2003, The Finite Element Method: A Practical Course, Elsevier Butterworth-Heinemann, Burlington, MA.
Intel Math Kernel Library 11 Update 5, 2013. Available at: https://software.intel.com/en-us/intel-mkl
Xiong, S., Lin, C., Wang, Y., Liu, W., and Wang, Q. J., 2010, “An Efficient Elastic Displacement Analysis Procedure for Simulating Transient Conformal-Contact Elastohydrodynamic Lubrication Systems,” ASME J. Tribol., 132(2), p. 021502. [CrossRef]
Li, S., and Kahraman, A., 2010, “A Transient Mixed Elastohydrodynamic Lubrication Model for Spur Gear Pairs,” ASME J. Tribol., 132(1), p. 011501. [CrossRef]
Chang, L., 2000, “A Simple and Accurate Method to Calculate Transient EHL Film Thickness in Machine Components Undergoing Operation Cycles,” Tribol. Trans., 43(1), pp. 116–122. [CrossRef]
Gordon, R., 1987, Calculation and Measurement Techniques for Momentum, Energy and Mass Transfer (Series C), Module 4, Vol. 7, American Institute of Chemical Engineers. New York.
Patankar, S., 1980, Numerical Heat Transfer and Fluid Flow, Hemisphere Publishing Corporation, New York.
Roelands, C., 1966, Correlational Aspects of the Viscosity–Temperature–Pressure Relationship of Lubricating Oils, V. R. B. Druk, Groningen, The Netherlands.
Dowson, D., and Taylor, C., 1967, “Elastohydrostatic Lubrication of Circular Plate Thrust Bearings,” ASME J. Lubr. Technol., 89(3), pp. 237–242. [CrossRef]
Manring, N., Johnson, R., and Cherukuri, H., 2002, “The Impact of Linear Deformations on Stationary Hydrostatic Thrust Bearings,” ASME J. Tribol., 124(4), pp. 874–877. [CrossRef]


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Fig. 3

Slipper fluid film discretization

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Fig. 4

Illustration of slipper pocket pressure control volume

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Fig. 2

Free body diagram of the slipper [1]

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Fig. 1

Cross section of an axial piston pump [1]

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Fig. 5

Illustration of the solid body deformation pressure loads and constraints

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Fig. 6

Illustration of moving swashplate deformation

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Fig. 10

Hydrostatic (320 bar pocket pressure) pressure deformation of the slipper

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Fig. 7

Swashplate pressure deformation

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Fig. 15

Slipper film thicknesses with a rigid swashplate (a) transient deformation effects considered Reynolds formulation and (b) no transient deformation consideration

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Fig. 16

Comparison of rigid-swashplate simulations with (a) the full model and (b) the slipper transient deformation neglected

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Fig. 8

Thermal boundary conditions for the slipper and swashplate

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Fig. 9

Flow diagram of the complete numerical scheme

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Fig. 11

Mean absolute slipper (a) and swashplate (b) total and hydrodynamic-isolated deformation

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Fig. 12

Simulation results of exploded slipper fluid film thickness

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Fig. 13

Simulation of exploded slipper fluid film thickness neglecting transient deformation squeeze pressure contributions

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Fig. 14

Slipper film thicknesses (a) transient deformation effects considered in Reynolds formulation and (b) no transient deformation consideration



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