NUMERICAL AND EXPERIMENTAL INVESTIGATION ON O-RING-SEALS IN DYNAMIC APPLICATIONS

Authors

  • Alexander Wohlers Institute for Fluid Power Drives and Controls (IFAS), RWTH Aachen University, Steinbachstraße 53, 52074 Aachen, Germany
  • Oliver Heipl Institute for Fluid Power Drives and Controls (IFAS), RWTH Aachen University, Steinbachstraße 53, 52074 Aachen, Germany
  • Bo N. J. Persson Institut für Festkörperforschung (IFF), Forschungszentrum Jülich, 52425 Jülich, Germany
  • Michele Scaraggi DIMeG-Politecnico di Bari, V.le Japigia 182, I-70126 Bari, Italy
  • Hubertus Murrenhoff Institute for Fluid Power Drives and Controls (IFAS), RWTH Aachen University, Steinbachstraße 53, 52074 Aachen, Germany

Keywords:

hydraulics, pneumatics, o-ring seal, finite element analysis FEA, gap flow, rubber friction, contact mechanics, fluid structure interaction

Abstract

This paper presents a physically-based simulation approach to predict the friction force at oil lubricated contacts for rubber o-ring seals in dynamic applications. In the boundary lubrication regime the friction coefficient is calculated using a recently developed contact mechanics theory. The stress and strain fields in the rubber are calculated using the finite element analysis (FEA). In the FEA the temperature-dependent nonlinear rubber behaviour is considered. Loads due to the assembly process, thermal expansion, system pressure and tangential friction forces are included in the analysis. In the mixed and hydrodynamic lubrication regimes, the asperity-asperity and fluid-asperity interactions are determined from the Persson's dry-contact mechanics theory, the Reynolds-equation (gap flow) and the deformation model of the seal. To test the theory a test rig has been developed. Simulation results, carried out for an unpressurized o-ring seal system, are compared to the experimental data and, especially for small velocities where mixed lubrication prevails, the results are in good agreement.

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Author Biographies

Alexander Wohlers, Institute for Fluid Power Drives and Controls (IFAS), RWTH Aachen University, Steinbachstraße 53, 52074 Aachen, Germany

Alexander Wohlers Born in 1979 in Saarburg, Germany. Studied mechanical engineering at the University of Applied Sciences Trier. Finished his diploma thesis in September 2005 in the field of hydraulic seal technology. Since November 2005 he is member of the scientific staff of Institute for Fluid Power Drives and Controls at RWTH Aachen University.

Oliver Heipl, Institute for Fluid Power Drives and Controls (IFAS), RWTH Aachen University, Steinbachstraße 53, 52074 Aachen, Germany

Oliver Heipl Born in 1982 in Biberach an der Riß, Germany. Studied mechanical engineering at RWTH Aachen University. Finished his diploma thesis in October 2008 in the field of static and dynamic simulation of reciprocal pneumatic O-Ring-Seals. Since November 2008 he is member of the scientific staff of Institute for Fluid Power Drives and Controls at RWTH Aachen University.

Bo N. J. Persson, Institut für Festkörperforschung (IFF), Forschungszentrum Jülich, 52425 Jülich, Germany

Bo N. J. Persson Born in 1952, is a research scientist at IFF, Research Center Jülich. Presently his main research activity is in tribology (adhesion, friction and contact mechanics) and surface science, in particular dynamical processes at surfaces, and biophysics.

Michele Scaraggi, DIMeG-Politecnico di Bari, V.le Japigia 182, I-70126 Bari, Italy

Michele Scaraggi Born in 1982 in Terlizzi, Italy. Studied mechanical engineering at the Technical University of Bari, Italy. Finished his diploma thesis in November 2006 in the field of MEMS technology. Since January 2007 he is member of the scientific staff of Department of Mechanical Engineering at the Technical University of Bari.

Hubertus Murrenhoff, Institute for Fluid Power Drives and Controls (IFAS), RWTH Aachen University, Steinbachstraße 53, 52074 Aachen, Germany

Hubertus Murrenhoff Βorn in 1953 he is Director of the Institute for Fluid Power Drives and Controls (IFAS) at RWTH Aachen University, Germany. Main research interests cover hydraulics and pneumatics including components, systems, controls, simulation programs and the applications of fluid power in mobile and stationary equipment.

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Published

2009-11-01

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