NAFEMS International Journal of CFD Case Studies

Volume 8, January 2009

ISSN 1462-236X

Analysis of unsteady fluid flow inside fluid power components – a challenge to CFD-simulation

Rüdiger, F., Leonhard, A., Wustmann, W. und Helduser, S.
Technische Universität Dresden, Institut für Fluidtechnik, 01062 Dresden, Germany

https://doi.org/10.59972/nafcbany

Keywords: Hydraulics, Pneumatics, Valve, Hydrostatic Pump, Mesh Adaptation, Moving and Deforming Mesh, and Cavitation

Abstract

Hydraulic and pneumatic valves and hydrostatic pumps are key-components of fluid power drive and control systems. Due to their inherent transient operating conditions and the moving devices included they are posing challenges for numerical simulation. Unsteady fluid flow, moving and deforming flow domain and strong nonlinearities caused by physical phenomenon like aeration and cavitation in hydraulics and shock waves in pneumatics are some of them. Another aspect of increasing importance in design of fluid power components is the need of reduced pulsation and noise emission. Special aspects for CFD in hydraulics and pneumatics therefore are

• time dependent changes in size and shape of flow geometry,
• mesh adaptation for fitting of shock waves in pneumatic flow,
• fluid borne noise and cavitating in hydraulics and
• combination of lumped element simulation and CFD simulation.

On the basis typical products – a pneumatic pressure control valve, a hydraulic proportional valve and an external gear pump – the capability of modern commercial CFD-codes will be illustrated. The results show the ability of CFD tools for design and engineering in fluid power industry.

References

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[4] Fiedler, M.; Helduser, S.; Rüdiger, F.: ”Geometry based design of high dynamic servo-pneumatic valves”, 4th FPNI-PhD Symposium, Sarasota/Florida, June 13th – 17th, 2006

[5] Rüdiger, F., Helduser, S.: “Untersuchungen zur Schallabstrahlung ölhydraulischer Ventile“, O+P Zeitschrift für Fluidtechnik 48 (2004) 4, 248-252 and 5, 328-331

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[8] Wustmann, W.; Helduser, S.; Wimmer, W.: “CFD-Simulation des Umsteuervorgangs von Außenzahnradpumpen”, 6th IFK, Dresden, March 31th – April 2nd, 2008 (accepted)

[9] Wehner, D.: “Modellbasierter Systementwurf am Beispiel vorgesteuerter Druckbegrenzungsventile”, Dissertation, TU Dresden, 2008

Cite this paper

Rüdiger, F., Leonhard, A., Wustmann, W., Helduser, S., Analysis of unsteady fluid flow inside fluid power components – a challenge to CFD-simulation, NAFEMS International Journal of CFD Case Studies, Volume 8, 2009, Pages 29-37, https://doi.org/10.59972/nafcbany