• Stefan Gels Institute for fluid power drives and controls (IFAS) of RWTH Aachen University
  • Hubertus Murrenhoff Institute for fluid power drives and controls (IFAS) of RWTH Aachen University


lubricating film, Reynolds-equation, axial piston machines


Axial piston pumps are used in several industrial applications. The geometry of the probably most important interface of these pumps, the piston-cylinder-contact, is mostly optimized by comparing test bench results. Only a few simulation tools have ever been used to optimize the geometry such as gap width, cylinder length, etc. For the DFG-supported project “Axial piston machines with PVD-coated components” both, piston and cylinder, are to be coated or should consist of hardened material, so that running-in is no longer possible. The contour of piston and cylinder therefore needs to be machined before the parts are used in the axial piston pump. Simulations of different contours as well as gap widths and cylinder lengths are therefore necessary to avoid a large number of test-bench measurements. In this publication a simulation tool is presented, which allows to vary the geometry and contouring of the moving parts. It is shown that the contouring and geometry can be optimized for specific working points.


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Author Biographies

Stefan Gels, Institute for fluid power drives and controls (IFAS) of RWTH Aachen University

Stefan Gels Born on December 15th, 1981, he received his degree in mechanical engineering (Dipl.-Ing.) at RWTH Aachen University, Germany in 2008. Since 2008 he has been member of the scientific staff at the Institute for Fluid Power Drives and Controls (IFAS) at RWTH Aachen University.

Hubertus Murrenhoff, Institute for fluid power drives and controls (IFAS) of RWTH Aachen University

Hubertus Murrenhoff Born on August 13th, 1953, he is director of the Institute for Fluid Power Drives and Controls (IFAS) and dean of faculty of mechanical engineering 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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