• Uwe Wieczorek Technical University of Hamburg-Harburg, Institute for Aircraft Systems Engineering, Nesspriel 5, 21129 Hamburg, Germany
  • Monika Ivantysynova Technical University of Hamburg-Harburg, Institute for Aircraft Systems Engineering, Nesspriel 5, 21129 Hamburg, Germany


axial piston machine, non-isothermal gap flow, prediction of losses, computer aided design of swash plate machines


The simulation tool CASPAR (Calculation of swash plate type axial piston pump and motor) is presented in this pa-per. Based on the simulation of the flow through the lubricating gaps in swash plate type axial piston machines the pres-sure, velocity and temperature fields in the considered gaps can be determined. This allows the calculation of the main losses generated in the machine due to viscous friction and gap flow. The individual gaps are connected in a complex way to each other. The calculation of the gap flow requires the determination of the instantaneous gap heights for all considered gaps. This is realized by solving the motion equation for all moveable parts of the rotating group. For deter-mination of pressure dependent external forces the instantaneous pressure in the displacement chamber is calculated simultaneously. The program further calculates the instantaneous inlet and outlet flow of the swash plate machine for pumping and motoring mode as well as internal volumetric losses.


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Author Biographies

Uwe Wieczorek, Technical University of Hamburg-Harburg, Institute for Aircraft Systems Engineering, Nesspriel 5, 21129 Hamburg, Germany

Uwe Wieczorek Born on June 4th 1968 in Hamburg (Germany) Study of Mechanical Engineering at the TU Hamburg-Harburg. Scientific Employee at the Department of Measurement and Control Engineering of the Gerhard Mercator Univer-sity of Duisburg. Scientific Employee at the Institute for Aircraft Systems Engineering at the Technical University of Hamburg-Harburg.

Monika Ivantysynova, Technical University of Hamburg-Harburg, Institute for Aircraft Systems Engineering, Nesspriel 5, 21129 Hamburg, Germany

Monika Ivantysynova Born on December 11th 1955 in Polenz (Germany). She received her MSc. Degree in Mechanical Engineering and her PhD. Degree in Hydraulics from the Slovak Technical University of Bratislava, Czechoslovakia. After 7 years in fluid power industry she returned to university. In April 1996 she received a Professorship in fluid power & control at the University of Duisburg (Germa-ny). At present she is Professor of Mechatron-ic Systems at the Technical University of Hamburg-Harburg. Her research centres around the optimisation of displacement machines, advanced system design and motion control as well as modelling, simula-tion and testing of fluid power systems. Besides the book “Hydrostatic Pumps and Motors” published in German and English, she has published approximately 45 papers in technical journals and at international confer-ence


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