A novel design concept for variable delivery flow external gear pumps and motors

Authors

  • Ram Sudarsan Devendran Maha Fluid Power Research Center, School of Mechanical Engineering, Purdue University 1500 Kepner Dr, Lafayette, IN 47905, USA
  • Andrea Vacca Maha Fluid Power Research Center, School of Mechanical Engineering, Purdue University 1500 Kepner Dr, Lafayette, IN 47905, USA

DOI:

https://doi.org/10.1080/14399776.2014.977699

Keywords:

external gear pumps and motors, variable displacement, variable delivery, pump optimization, energy efficiency

Abstract

This paper presents an original concept for variable delivery external spur gear machines, which combines the well-known advantages of these units (such as low cost, good reliability, acceptable efficiency) – traditionally fixed displacement – in a solution capable of varying the amount of flow displaced at each shaft revolution. The proposed design concept realizes a variable timing for the connections of each tooth space volume with the inlet and outlet ports, through a movable element (“slider”) placed at the gears lateral side. The position of the slider determines the amount of flow displaced by the unit per revolution. In order to extend the range of flow variation achievable by the unit, an asymmetric involute tooth profile for the gears was proposed. A multi-objective genetic algorithm was used to optimize the design of the gears along with the design of the timing grooves in the slider. This algorithm is based on the HYGESIM (HYdraulic GEar machines Simulator) tool developed by the authors’ research group for the evaluation of the performance of every particular design. The optimal design solution, capable of achieving 40% flow variation (from 100% to 60%), was realized in a working proof of concept and tested for the case of a pump, although the solution is in principle valid for both pumps and motors. Experimental results were in line with the numerical predictions and show the potential of this design concept of achieving flow variations in an energy efficient fashion, with volumetric and hydro-mechanical efficiency at reduced displacements in line with other state of the art variable displacement units.

Therefore, the proposed design can impact current applications for external gear pumps and motors, offering the additional flow-on-demand capability. Furthermore, it can be utilized in several other engineering applications in which traditional external gear machines were not a viable alternative because of their intrinsic fixed displacement nature.

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Author Biographies

Ram Sudarsan Devendran, Maha Fluid Power Research Center, School of Mechanical Engineering, Purdue University 1500 Kepner Dr, Lafayette, IN 47905, USA

Ram Sudarsan Devendran received his Masters’ degree in Mechanical Engineering from Purdue University in 2012. Currently he is a PhD candidate whose research interests include the development of a novel design of variable displacement type external gear machines. Also, his research focusses on optimization of the designs of the external gear machines focusing on unconventional gear profiles, based on a multitude of performance features.

Andrea Vacca, Maha Fluid Power Research Center, School of Mechanical Engineering, Purdue University 1500 Kepner Dr, Lafayette, IN 47905, USA

Andrea Vacca received his Masters’ degree in Mechanical Engineering from the University of Parma (Italy) in 1999 and his Doctorate in Energy Systems from the University of Florence (Italy) in 2005. He is currently an Associate Professor for the School of Mechanical engineering as well the Agricultural & Biological Department. His current research includes a broad range of analysis, modeling and testing of fluid power systems and hydraulic components. Particular goals of his research are the improvement of energy efficiency and controllability of fluid power systems and the reduction of noise emissions of fluid power components. To accomplish the goals of his research, Prof. Vacca’s research team has developed original numerical techniques to simulate fluid power systems and components, especially gear machines and hydraulic control valves.

References

Borghi M., et al., 2006, The influence of cavitation and aeration

on gear pump and motors meshing volume pressures,

IMECE2006, ASME Int. Mechanical Engineering Congress

and Exposition, 5–10 November, Chicago, IL, USA.

Bowden, C., 1989, Variable discharge gear pump with energy

recovery, Patent Application Publication, US4824331.

Bowden, C., 1990, Variable discharge gear pump with energy

recovery, Patent Application Publication, US4902202.

Bussi, E., 1992, Variable delivery gear pump, European Patent

Application, EP0478514.

Clarke, J.M., 2002, Hydraulic transformer using a pair of variable

displacement gear pumps, Patent Application Publication,

US2002104313.

Devendran, R.S. and Vacca, A., 2013a, Design potentials of

external gear machines with asymmetric tooth profile, Proceedings

of the ASME/Bath Symposium on Fluid Power &

Motion Control, 6–9 October, Sarasota, FL, USA.

Devendran, R.S. and Vacca, A., 2013b. Optimal design of gear

pumps for exhaust gas aftertreatment applications. Simulation

Modelling Practice and Theory, 38, 1–19.

Devendran, R.S. and Vacca, A., 2012, Optimal design of gears

and lateral bushes of external gear machines, Proceedings

of the Bath/ASME Symposium on Fluid Power and Motion

Control, 10–12 September, Bath, UK.

Dhar, S. and Vacca, A., 2013. A fluid structure interaction-

EHD model of the lubricating gaps in external gear

machines: formulation and validation. Tribology International,

, 78–90.

Eaton, M., Keogh, P.S., Edge, K.A., 2006, The Modelling,

Prediction, and Experimental Evaluation of Gear Pump

Meshing Pressure with Particular Reference to Aero-Engine

Fuel Pumps. Proceedings of the Institution of Mechanical

Engineers, Part I: Journal of Systems and Control

Engineering, 220–365.

Ehasan, M, Rampen, W.H., and Salter, S.H., 1996. Computer

Simulation of the Performance of Digital Displacement

Pumps-Motors. ASME International Mechanical Engineering

Congress and Exposition, 19–24, Atlanta, GA, USA.

Fiebig, W. 2007. Location of Noise Sources in Fluid Power

Machines. International Journal of Occupational Safety

and Ergonomics, 13 (4), 441–450.

Hoji, T., Nagao, S., Shinozaki, K. 2008 Gear Pump, Patent

Application Publication, US2008044308.

Ivantysynova, M. 1998. Pump Controlled Actuator – a Realistic

Alternative for Heavy Duty Manipulators and Robots.

International Scientific Forum in Fluid Power Control of

Machinery and Manipulators, Cracow, Fluid Power Net

Publication, 2000 (5), 101–123.

Ivantysyn, J. and Ivantysynova, M. 2001. Hydrostatic Pumps

and Motors, Principles, Designs, Performance, Modelling,

Analysis, Control and Testing. New Delhi. Academia

Books International, ISBN -81-85522-16-2.

Kapelevich, A., 2000. Geometry and Design of Involute Spur

Gears with Asymmetric Teeth. Mechanism and Machine

Theory, 35, 117–130.

Kumar, V.S., Muni. D.V., and Muthuveerappan. G., 2008. Optimization

of Asymmetric Spur Gear Drives to Improve the

Bending Load Capacity. Mechanism and Machine Theory,

, 829–838.

Litvin, F.L. and Fuentes, A., 2004. Gear Geometry and Applied

Theory. 2nd ed. Cambridge University Press.

Mahrenholz, J. and Lumkes, J.J., 2009. Model Development

and Experimental Analysis of a Virtually Variable Displacement

Pump System. International Journal of Fluid Power,

(3), 17–27.

Manco, S., Nervegna, N., and Rundo, M., 2004, Displacement

vs Flow Control in IC Engines Lubricating Pumps. Proceedings

of the 2004 SAE World Congress, (2004-01-

, Detroit, MI, USA.

Merrill, K., Breidi, F.Y., and Lumkes, J., 2013. Simulation

Based Design Optimization of Digital Pumps/Motors,

ASME/Bath Symposium on Fluid Power and Motion Control,

-9 October, Sarasota, FL, USA.

Murrenhoff, H., Sgro, S., Vukovic, M., 2014, An Overview of

Energy Saving Architectures for Mobile Applications,

Proceedings of 9th International Fluid Power Conference,

–26 March , Aachen, Germany.

Nagamura, K., Ikejo, K. and Tutulan, F.G., 2004. Design and

Performance of Gear Pumps with a Non-Involute Tooth Profile.

Proceedings of the Institution of Mechanical Engineers,

Part B: Journal of Engineering Manufacture, 218, 699–711.

Nieling, M., Fronczak F.J., Beachley N.H., 2005. Design of a

Virtually Variable Displacement Pump/Motor. Proceedings

of the 50th National Conference on Fluid Power, Las

Vegas, 2005.

Opperwall, T. and Vacca, A., 2013. A combined FEM/BEM

model and experimental investigation into the effects of

fluid-borne noise sources on the air-borne noise generated

by hydraulic pumps and motors, Proceedings of the Institution

of Mechanical Engineers, Part C: Journal of Mechanical

Engineering Science, 1–15.

Poloni, C., et al., 2000. Hybridization of a Multi-Objective

Genetic Algorithm, a Neural Network and a Classical

Optimizer for a Complex Design Problem in Fluid Dynamics.

Computer Methods in Applied Mechanics and Engineering,

, 403–420.

Rannow, M.B. Li, P.Y., 2009. Soft Switching Approach to

Reducing Transition Losses in an ON/OFF Hydraulic

Valve. Proceedings of the ASME 2009 Dynamic Systems

and Control Conference, 12–14 October, Hollywood,

California, USA.

Reiners, W. and Wiggermann, W., 1960, Variable Delivery

Gear Pumps. The Patent Office London, GB968998.

Shigley, J.E. and Mischke, C.R., 1996, Standard Handbook of

Machine Design. 2nd ed. Mc Graw Hills, New York, NY,

USA.

Tomlinson, S.P. and Burrows, C.P., 1992. Achieving a Variable

Flow Supply by Controlled Unloading of a Fixed- Displacement

Pump. ASME Journal of Dynamic Systems Measurement

and Control, 114 (1), 166–171.

Vacca, A. and Guidetti, M. 2011. Modelling and experimental

validation of external spur gear machines for fluid power

applications. Simulation and Modeling Practice and Theory,

, 2007–2031.

Vacca A., Franzoni G., and Casoli, P., 2007, On the Analysis of

Experimental Data for External Gear Machines and their

Comparison with Simulation Results, ASME International

Mechanical Engineering Congress and Exposition, 11–15

November, 2007, Seattle, WA.

Winmill, L.F., 2001. Adjustable-Displacement Gear Pump. Patent

Application Publication, US2001024618.

Yang, D. Zhong, D., 1987, Radial-Movable Variable Displacement

Gear Pump (Motor). CN85109203.

Zhou, J., Vacca, A., and Casoli, P., 2014. A Novel Approach

for Predicting the Operation of External Gear Pumps under

Cavitating Conditions. Simulation Modeling Practice and

Theory, 45, 35–49.

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Published

2014-11-01

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Original Article