A Quick-and-Dirty Method for Assessing the Risk of Negative Aeration Effects of Shock Absorbers Equipped with Shim Sliding Base Valves

Piotr Czop; Jacek Gniłka

doi:10.24423/cames.338

Piotr Czop AGH University of Science and Technology
Jacek Gniłka Silesian University of Technology

DOI: http://dx.doi.org/10.24423/cames.338

Abstract

This paper presents a quick-and-dirty method to assess the risk of negative aeration effects occurring in twin-tube hydraulic shock absorbers used in passenger cars at the early design stage. The method is intended to be implemented as an engineering calculation tool based on the computational fluid dynamics (CFD) two-dimensional (2D)/three-dimensional (3D) steady-state single-phase model. The CFD model was previously validated with the use of the particle image velocimetry (PIV) experiment. The negative aeration effect is a wellknown issue for automotive and railway shock absorbers manufacturers. It results in uncontrolled on-vehicle vibrations and the deteriorated shock absorber damping characteristic. The major aeration contributor in twin-tube hydraulic shock absorbers is the sliding shim intake valve, which requires design optimization to avoid a negative aeration effect. The method validation was conducted with the customized test rig equipped with a transparent cylinder where the specific sliding intake valve was assembled. The proposed method also requires a lumped-parameter model of a twin-tube shock absorber, which allows to simulate boundary conditions in assessing particular reservoirs of a shock absorber, i.e., pressures and flow balance. The method is implemented as a calculation routine that converts CFD pressure regions into a gas concentration indicator (GCI) using the pressure-density characteristic of an oil-gas emulsion of a shock absorber. GCI is calculated based on the sum of particular 2D/3D grid elements. The method application is to minimize the risk of occurrence of negative aeration effects by avoiding expensive and time-consuming experimental tests. This method can also be used for in-production shock absorbers projects as a part of a continuous improvement cycle or in the case of inefficient shock absorbers claimed by a vehicle manufacturer. The application scope of the method can be extended for arbitrary twin-tube designs of shock absorbers in the automotive and railway industries.

Keywords

twin-tube, passenger car, shock absorber, PIV, CFD, quick-and-dirty, optical measurements, vibrations, simulation model, aeration effect, sliding intake valve, shimrelief valve,

References

1. M. Alonso, Á. Comas, Modelling a twin tube cavitating shock absorber, Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 220(8): 1031–1040, 2006, doi: 10.1243/09544070D23104.
2. C.E. Brennen, Cavitation and Bubble Dynamics, Cambridge University Press, 2014.
3. G. Cavazzini [Ed.], The Particle Image Velocimetry: Characteristics, Limits and Possible Applications, InTechOpen, London, 2012.
4. S.L. Ceccio, C.E. Brennen, Observations of the dynamics and acoustics of travelling bubble cavitation, Journal of Fluid Mechanics, 233: 633–660, 1991, doi: 10.1017/S0022112091000630.
5. P. Czop, J. Gniłka, Reducing aeration and cavitation effect in shock absorbers using fluidstructure interaction simulation, Computer Assisted Methods in Engineering and Science, 23(4): 171–189, 2016, https://cames.ippt.pan.pl/index.php/cames/article/view/181.
6. P. Czop, M. Hetmanczyk, G. Wszołek, J. Słoniewski, D. Gasiorek, Z. Bulinski, Particle image velocimetry technique applied to flow evaluation through a shock absorber intake valve, [in:] 4th International Conference Mechatronics: Ideas for Industrial Applications, September 13–15, Gliwice, Wisła-Jawornik, Poland, pp. 38–39, 2017.
7. P. Czop, D. Slawik, A high-frequency first-principle model of a shock absorber and servohydraulic tester, Mechanical Systems and Signal Processing, 25(6): 1937–1955, 2011, doi: 10.1016/j.ymssp.2011.01.011.
8. P. Czop, D. Sławik, T. Wlodarczyk, M. Wojtyczka, G. Wszołek, Six Sigma methodology applied to minimizing damping lag in hydraulic shock absorbers, Journal of Achievements in Materials and Manufacturing Engineering, 49(2): 243–250, 2011.
9. P. Czop, G. Wszołek, M. Hetmanczyk, J. Dawid, A device to determine the parameters of passive valve operation, particularly disc valves of hydraulic dampers, using PIV method (granted patent), Silesian University, PL407553; PL222810, 2015.
10. P. Czop, G. Wszołek, M.P. Hetmanczyk, The effects of the aeration phenomenon on the performance of hydraulic shock absorbers, [in:] A. Mezyk, S. Kciuk, R. Szewczyk, S. Duda [Eds.], Modelling in Engineering 2020: Applied Mechanics. SMWM 2020. Advances in Intelligent Systems and Computing, vol 1336, Cham, Springer, 2020, doi: 10.1007/978-3-030-68455-6_2.
11. R. Andrighetto, Dynamic and thermal model for hydraulic shock absorbers, PhD Thesis, Politecnico di Torino, 2018.
12. N.G. Deen, J. Westerweel, E. Delnoij, Two-phase PIV in bubbly flows: status and trends, Chemical Engineering & Technology, 25(1): 97–101, 2002, doi: 10.1002/1521-4125(200201)25:1<97::AID-CEAT97>3.0.CO;2-7.
13. J. Dixon, The Shock Absorber Handbook, John Wiley & Sons, 2007.
14. S. Duym, R. Stiens, K. Reybrouck, Evaluation of shock absorber models, Vehicle System Dynamics, 27(2): 109–127, 1997, doi: 10.1080/00423119708969325.
15. S.W. Duym, R. Stiens, G. Baron, K. Reybrouck, Physical modeling of the hysteretic behaviour of automotive shock absorbers, SAE Technical Paper No. 970101, Society of Automotive Engineers, 1997, doi: 10.4271/970101.
16. C.O. Iyer, W.-J. Yang, Analysis on liquid-vapor bubbly-flow systems in reciprocating motion, Journal of Fluids Engineering, 121(1): 185–190, 1999, doi: 10.1115/1.2822000.
17. R. Van Kasteel, C.-G. Wang, L. Qian, J.-Z. Liu, G.-H. Ye, A new shock absorber model for use in vehicle dynamics studies, Vehicle System Dynamics, 43(9): 613–631, 2005, doi: 10.1080/0042311042000266720.
18. B. Koren, P.F.M. Michielsen, J.-W. Kars, P. Wesseling, A computational method for high-frequency oleodynamics: application to hydraulic-shock-absorber designs, Surveys on Mathematics for Industry, 7: 283–301, 1998.
19. J.C. LaJoie, Damper Performance Development, SAE Technical Paper No. 962551, Society of Automotive Engineers, 1996, doi: 10.4271/962551.
20. J.L. Lebowitz, O. Penrose, Modern ergodic theory, Physics Today, 26(2): 23–29, 1973.
21. K. Lee, Numerical modelling for the hydraulic performance prediction of automotive monotube dampers, Vehicle System Dynamics, 28(1): 25–39, 1997, doi: 10.1080/00423119708969347.
22. F. Luo, X.L. Zhang, A review of aeration and cavitation phenomena in the hydraulic shock absorber, [in:] Advances in Mechatronics, Robotics and Automation II, Trans Tech Publications, Ltd, vol. 536–537, pp. 1369–1373, 2014, doi: 10.4028/www.scientific.net/amm.536-537.1369.
23. F. Menter, Zonal two equation k - w turbulence models for aerodynamic flows, [in:] 23rd Fluid Dynamics, Plasmadynamics, and Lasers Conference, AIAA-93-2906, 1993, doi: 10.2514/6.1993-2906.
24. G. Morettini, N. Bartolini, D. Astolfi, L. Scappaticci, M. Becchetti, F. Castellani, Experimental diagnosis of cavitation for a hydraulic monotube shock absorber, Diagnostyka, 17(3): 75–80, 2016.
25. MSC.Software Corporation, MSC.Nastran 2001. Getting Started with MSC.Nastran. User’s Guide, MSC Software Corporation, Santa Ana, CA, 2000, www.ae.metu.edu.tr/~ae464/getstart.pdf.
26. S.V. Patankar, Numerical Heat Transfer and Fluid Flow, CRC Press, Boca Raton, 2018.
27. M. Raffel, C.E. Willert, F. Scarano, C.J. Kähler, S.T. Wereley, J. Kompenhans, Particle Image Velocimetry: A Practical Guide, Springer, 2013.
28. S.M. Rifai, J.C. Buell, Z. Johan, J.A. Landers, A.B. Glendinning, J.A. Landers, Automotive engineering Applications of Multiphysics Simulation, SAE Technical Paper 1999-01-1022, Society of Automotive Engineers, 1999, doi: 10.4271/1999-01-1022.
29. F. Martins, C. Siqueira, N. Spogis, Development and validation of a CFD model to investigate the oil flow in a shock absorber, SAE Technical Paper 2005-01-4030, 2005, doi: 10.4271/2005-01-4030.
30. D. Sławik, P. Czop, A. Król, G. Wszołek, Optimization of hydraulic dampers with the use of Design For Six Sigma methodology, Journal of Achievements in Materials and Manufacturing Engineering, 43(2): 676–683, 2010.
31. H.K. Versteeg, W. Malalasekera, An Introduction to Computational Fluid Dynamics: The Finite Volume Method, Pearson Education, 2007.
32. G. Del Vescovo, A. Lippolis, S. Camporeale, Investigation of the flow field inside fluid power directional control valves by means of particle image velocimetry, [in:] Atti Del XIV Convegno Nazionale Aivela-Roma, November 6–7, 2006.
33. T.H. Włodarczyk, P. Czop, D. Sławik, G. Wszołek, Automatic shape identification by data-driven algorithms with applications to design optimizing in hydraulics, Journal of Transdisciplinary Systems Science, 16(1): 35–43, 2012.
34. T. Xing, J. Shao, F. Stern, BKW-RS-DES of unsteady vortical flow for KVLCC2 at large drift angles, [in:] Proceedings of the 9th International Conference on Numerical Ship Hydrodynamics, Ann Arbor, Michigan, August 5–8, 19 pages, 2007.
35. F. Herr, T. Mallin, J. Lane, S. Roth, A Shock Absorber Model Using CFD Analysis and Easy5, SAE Technical Paper 1999-01-1322, 1999, doi: 10.4271/1999-01-1322.
36. M. Shams, R. Ebrahimi, A. Raoufi, B.J. Jafari, CFD-FEA analysis of hydraulic shock absorber valve behavior, International Journal of Automotive Technology, 8(5): 615–622, 2007.
37. S.S. Kulkarni, B. Ravi, M. Magdum, A Nonlinear Contact Analysis of An Automotive Shock Absorber Shims Using Fluid Structure Interaction Technique, [in:] Altair Technology Conference, India, 2013.
38. F.G. Guzzomi, P. O’neill, A. Tavner, Investigation of Damper Valve Dynamics Using Parametric Numerical Methods, [in:] 16th Australasian Fluid Mechanics Conference Crown Plaza, Gold Coast, Australia, December 2–7, 2007.