Experimental diagnosis of cavitation for a hydraulic monotube shock absorber

• Autorzy: Morettini G. , Bartolini N. , Astolfi D. , Scappaticci L. , Becchetti M. , Castellani F.
• Języki publikacji: EN

Abstrakty

EN

Hydraulic shock absorbers are mechanical devices responsible of vibration damping. Although a high level of development and tuning has been carried on, in order to ensure high performance standards in almost every situation, some dynamic phenomenon affecting internal fluid may reduce the damping capacity. In hydraulic shock absorbers, the energy is dissipated forcing the internal fluid through calibrated orifices; this energy is converted in heat and dispersed outwards from the external walls. Hydraulic fluid has therefore a fundamental role for the proper functioning of the overall device, and the most important variations of its chemical-physical properties have to be considered. One of the most dangerous phenomena involving the internal fluid is cavitation, which could affect performances and generate structural damages of the internal components of the damper. The aim of this work is to diagnose the phenomenon of cavitation using experimental data from a prototype of monotube shock absorber equipped with transparent walls and developed for research purposes. The identification of force and displacement parameters is carried out through experimental tests on the prototype, which is a totally adjustable device equipped with pressure and temperature transducers for every chamber. The optical access provided from the transparent wall allows to collect images from a high-speed camera, which could be related to the signals coming from the transducers. This approach is valuable for analyzing the occurrence and the time development of dynamic phenomena of cavitation of the flow or the motion of the main valve blades. Finally, the acquisition of the optical images, coupled with evidences from experimental data, allows to characterize the dynamic events of cavitation, from his onset.

Słowa kluczowe

EN

shock absorber; cavitation; shock transparent

PL

amortyzator hydrauliczny; kawitacja; diagnoza

• Wydawca: Polskie Towarzystwo Diagnostyki Technicznej
• Czasopismo: Diagnostyka
• Rocznik: 2016
• Tom: Vol. 17, No. 3
• Strony: 75--80
• Opis fizyczny: Bibliogr. 15 poz., rys.

Twórcy

autor

Morettini G.

• University of Perugia, Department of Engineering, Perugia, Italy

autor

Bartolini N.

• University of Perugia, Department of Engineering, Perugia, Italy

autor

Astolfi D.

• University of Perugia, Department of Engineering, Perugia, Italy

autor

Scappaticci L.

• University of Perugia, Department of Engineering, Perugia, Italy

autor

Becchetti M.

• University of Perugia, Department of Engineering, Perugia, Italy

autor

Castellani F.

• University of Perugia, Department of Engineering, Perugia, Italy

Bibliografia

• [1] BF Spencer Jr, SJ Dyke, MK Sain, and JDf Carlson. Phenomenological model for magnetorheological dampers. Journal of engineering mechanics, 1997.
• [2] Leser C, Renner T E, Salmon D C. Accurate shock absorber load modeling in an all terrain vehicle using black box neural network techniques. Technical report, SAE Technical Paper, 2002.
• [3] Beghi A, Liberati M, Mezzalira S, Peron S. Grey-box modeling of a motorcy- cle shock absorber for virtual prototyping applications. Simulation Modelling Practice and Theory, 15(8):894–907, 2007.
• [4] Witters M, and Swevers J. Black-box model identification for a continuously variable, electro-hydraulic semi-active damper. Mechanical Systems and Signal Processing, 24(1):4–18, 2010.
• [5] Lang H L. A study of the characteristics of automotive hydraulic dampers at high stroking frequencies. PhD thesis, 1977.
• [6] Duym S, Stiens R, Reybrouck K. Evaluation of shock absorber models. Vehicle system dynamics, 27(2):109–127, 1997.
• [7] Morman N K Jr. Modeling and identification procedure for the analysis and simulation of hydraulic shock absorber performance. Ford Motor Company, Michigan, 1984.
• [8] Mollica R, Youcef-Toumi K. A nonlinear dynamic model of a monotube shock absorber. In American Control Conference, 1997. Proceedings of the 1997, volume 1, pages 704-708. IEEE, 1997.
• [9] Cossalter V, Doria A, Pegoraro R, Trombetta L. On the non-linear behaviour of motorcycle shock absorbers. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 224(1):15–27, 2010.
• [10] Castellani F, Bartolini N, Scappatticci L, Astolfi D, Becchetti M. Numerical and experimental dynamics of a monotube shock absorber. SAE Technical Paper, 2016.
• [11] Dixon J. The shock absorber handbook. John Wiley & Sons, 2008.
• [12] Brennen C E. Cavitation and bubble dynamics, Oxford University Press (1995).
• [13] Katz D L. Prediction of the shrinkage of crude oils, «Drilling and Production Practice» (1942).
• [14] Allen M. Pressure-volume-temperature concentration relation of solutions, «ournal of Chemical Engineering Data (1970).
• [15] Bartolini N, Scappatticci L, Castellani F, Garinei A. The Knocking Noise on Twin Tube Shock Absorbers: Individuation and Analysis of the Phenomenon. SAE Technical Paper, 2016.