Iteration framework for solving mixed lubrication computation problems
Shi CHEN1, Nian YIN1, Xiaojiang CAI2, Zhinan ZHANG1()
1. State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240, China 2. Shanghai Aerospace Control Technology Institute, Shanghai 201109, China; Shanghai Key Laboratory of Aerospace Intelligent Control Technology, Shanghai 201109, China
The general discrete scheme of time-varying Reynolds equation loses the information of the previous step, which makes it unreasonable. A discretization formula of the Reynolds equation, which is based on the Crank–Nicolson method, is proposed considering the physical message of the previous step. Gauss–Seidel relaxation and distribution relaxation are adopted for the linear operators of pressure during the numerical solution procedure. In addition to the convergent criteria of pressure distribution and load, an estimation framework is developed to investigate the relative error of the most important term in the Reynolds equation. Smooth surface with full contacts and mixed elastohydrodynamic lubrication is tested for validation. The asperity contact and sinusoidal wavy surface are examined by the proposed discrete scheme. Results show the precipitous decline in the boundary of the contact area. The relative error suggests that the pressure distribution is reliable and reflects the accuracy and effectiveness of the developed method.
Semi-major axis and semi-minor axis of Hertz contact (m)
Synthetic elastic modulus (GPa)
Local film thickness (m)
Average film thickness
Distance between surfaces at without accounting for deformation (m)
A threshold value for checking the contacted state (m)
A threshold value for checking contacted boundary (m)
Roughness amplitude (m)
Dimensionless film thickness
i, j
Node number
Iteration step
Maximum iteration step
Wavelengths in x and y directions, respectively (m)
Hydrodynamic pressure, or pressure in general (Pa)
Maximum Hertzian contact pressure (Pa)
Pressure distribution error
Dimensionless pressure
Value of dimensionless pressure of previous iteration in node (i, j)
Value of dimensionless pressure of current iteration in node (i, j)
Spherical radius (m)
Synthetic curvature radius of contacted surface in x and y direction, respectively (m)
Time (s)
Dimensional time (s/m)
Entrainment speed (m/s)
Average speed in y direction (m/s)
Surface elastic deformation (m)
Applied load (N)
Load error
Leading edge of roughness surface (m)
Initial position (m)
Dimensionless length in direction
Dimensionless length in direction
Pressure–viscosity exponent (Pa–1)
Thermal diffusivity (W?m/°C)
The coefficient of dimensionless pressure
,
x- and y-coordinate of pressures when computing deformation, respectively
,
Tolerance of load and pressure, respectively
Relaxation factor of distributive relaxation method
Relaxation factor of Gauss–Seidel relaxation method
Temperature (°C)
Density (kg/m3)
Density under ambient condition (kg/m3)
Dimensionless density
Viscosity under ambient condition (Pa?s)
Effective viscosity (Pa?s)
Film thickness parameter
Composite root–mean–square roughness of contact surfaces
Reference shear stress (Pa)
Shear stress on the lower surface (Pa)
Absolute computation errors of governing equation
Pressure change of node (i, j) due to relaxation
Relative error
Control volume
Calculated domain
1
G E Morales-Espejel, P Rycerz, A Kadiric. Prediction of micropitting damage in gear teeth contacts considering the concurrent effects of surface fatigue and mild wear. Wear, 2018, 398–399: 99–115 https://doi.org/10.1016/j.wear.2017.11.016
2
V Brizmer, C Matta, I Nedelcu, et al.. The influence of tribolayer formation on tribological performance of rolling/sliding contacts. Tribology Letters, 2017, 65(2): 57 doi:10.1007/s11249-017-0839-3
3
V Brizmer, A Gabelli, C Vieillard, et al.. An experimental and theoretical study of hybrid bearing micropitting performance under reduced lubrication. Tribology Transactions, 2015, 58(5): 829–835 https://doi.org/10.1080/10402004.2015.1021944
4
N Patir, H S Cheng. An average flow model for determining effects of three-dimensional roughness on partial hydrodynamic lubrication. Journal of Tribology, 1978, 100(1): 12–17 https://doi.org/10.1115/1.3453103
5
K H Geng, A N Geng, X Wang, et al.. Frictional characteristics of the Vane–Chute pair in a rolling piston compressor based on the second-order motion. Tribology International, 2019, 133: 111–125 https://doi.org/10.1016/j.triboint.2018.11.030
6
C Liu, Y Lu, P Wang, et al.. Numerical analysis of the effects of compression ring wear and cylinder liner deformation on the thermal mixed lubrication performance of ring-liner system. Mechanics & Industry, 2018, 19(2): 203 doi:10.1051/meca/2018015
7
S H Cui, L Gu, M Fillon, et al.. The effects of surface roughness on the transient characteristics of hydrodynamic cylindrical bearings during startup. Tribology International, 2018, 128: 421–428 https://doi.org/10.1016/j.triboint.2018.06.010
8
S W Zhang, C H Zhang, Y Z Hu, et al.. Numerical simulation of mixed lubrication considering surface forces. Tribology International, 2019, 140: 105878 https://doi.org/10.1016/j.triboint.2019.105878
9
A Azam, A Ghanbarzadeh, A Neville, et al.. Modelling tribochemistry in the mixed lubrication regime. Tribology International, 2019, 132: 265–274 doi:10.1016/j.triboint.2018.12.024
10
X Jiang, D Y Hua, H S Cheng, et al.. A mixed elastohydrodynamic lubrication model with asperity contact. Journal of Tribology, 1999, 121(3): 481–491 https://doi.org/10.1115/1.2834093
11
Y Z Hu, D Zhu. A full numerical solution to the mixed lubrication in point contacts. Journal of Tribology, 2000, 122(1): 1–9 doi:10.1115/1.555322
12
Y Z Hu, H Wang, W Z Wang, et al.. A computer model of mixed lubrication in point contacts. Tribology International, 2001, 34(1): 65–73 https://doi.org/10.1016/S0301-679X(00)00139-0
13
X P Wang, Y C Liu, D Zhu. Numerical solution of mixed thermal elastohydrodynamic lubrication in point contacts with three-dimensional surface roughness. Journal of Tribology, 2017, 139(1): 011501 https://doi.org/10.1115/1.4032963
14
T He, D Zhu, C J Yu, et al.. Mixed elastohydrodynamic lubrication model for finite roller-coated half space interfaces. Tribology International, 2019, 134: 178–189 https://doi.org/10.1016/j.triboint.2019.02.001
15
D Zhu, J Wang, N Ren, et al.. Mixed elastohydrodynamic lubrication in finite roller contacts involving realistic geometry and surface roughness. Journal of Tribology, 2012, 134(1): 011504 https://doi.org/10.1115/1.4005952
X Q Lu, Q B Dong, K Zhou, et al.. Numerical analysis of transient elastohydrodynamic lubrication during startup and shutdown processes. Journal of Tribology, 2018, 140(4): 041504 https://doi.org/10.1115/1.4039371
18
S B Xiao. Numerical analysis of transient thermal mixed lubrication in point contact. Thesis for Master’s Degree. Wuhan: Wuhan University of Science and Technology, 2019 (in Chinese)
19
Y C He. Numerical analysis for the thermal EHL in point contacts of cam-tappet pair. Thesis for Master’s Degree. Qingdao: Qingdao University of Technology, 2019 (in Chinese)
20
J Marti, P. RyzhakovAn explicit/implicit Runge–Kutta-based PFEM model for the simulation of thermally coupled incompressible flows. Computational Particle Mechanics, 2020, 7(1): 57–69 https://doi.org/10.1007/s40571-019-00229-0
21
E Ezzatneshan, K Hejranfar. Simulation of three-dimensional incompressible flows in generalized curvilinear coordinates using a high-order compact finite-difference lattice Boltzmann method. International Journal for Numerical Methods in Fluids, 2019, 89(7): 235–255 https://doi.org/10.1002/fld.4693
Y Hamid, A Usman, S K Afaq, et al.. Numeric based low viscosity adiabatic thermo-tribological performance analysis of piston-skirt liner system lubrication at high engine speed. Tribology International, 2018, 126: 166–176 https://doi.org/10.1016/j.triboint.2018.05.022
24
S Z Wen, P Huang. Principles of Tribology. 2nd ed. Beijing: Tsinghua University Press, 2002
25
D Zhu. On some aspects of numerical solutions of thin-film and mixed elastohydrodynamic lubrication. Proceedings of the Institution of Mechanical Engineers. Part J, Journal of Engineering Tribology, 2007, 221(5): 561–579 doi:10.1243/13506501JET259
26
J D Anderson. Computational Fluid Dynamics: The Basics with Applications. New York: McGraw-Hill, 1995
27
S K Liao, Y Zhang, D Chen. Runge–Kutta finite element method based on the characteristic for the incompressible Navier–Stokes equations. Advances in Applied Mathematics and Mechanics, 2019, 11(6): 1415–1435 doi:10.4208/aamm.OA-2018-0150
28
M V Fischels, R G Rajagopalan. Family of Runge–Kutta-based algorithms for unsteady incompressible flows. AIAA Journal, 2017, 55(8): 2630–2644 https://doi.org/10.2514/1.J055106
29
X N Zhang, R Glovnea, G E Morales-Espejel, et al.. The effect of working parameters upon elastohydrodynamic film thickness under periodic load variation. Tribology Letters, 2020, 68(2): 62 https://doi.org/10.1007/s11249-020-01303-y
30
S B Liu, Q Wang, G Liu. A versatile method of discrete convolution and FFT (DC-FFT) for contact analyses. Wear, 2000, 243(1–2): 101–111 doi:10.1016/S0043-1648(00)00427-0
31
S Bair, Y Liu, Q J Wang. The pressure-viscosity coefficient for Newtonian EHL film thickness with general piezoviscous response. Journal of Tribology, 2006, 128(3): 624–631 https://doi.org/10.1115/1.2197846
32
C H Venner, A A Lubrecht. Multilevel Methods in Lubrication. Amsterdam: Elsevier, 2000
33
F R Lv, C X Jiao, N Ta, et al.. Mixed-lubrication analysis of misaligned bearing considering turbulence. Tribology International, 2018, 119: 19–26 https://doi.org/10.1016/j.triboint.2017.10.030
34
G Xiang, Y F Han, J X Wang, et al.. Coupling transient mixed lubrication and wear for journal bearing modeling. Tribology International, 2019, 138: 1–15 https://doi.org/10.1016/j.triboint.2019.05.011