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Clean Sky 2 – Project PALACE: Aeration’s Experimental Sound Velocity Investigations for High-Speed Gerotor Simulations

Authors: Benoît Mary, Thibaut Gras, Gaëtan Fagot, Yvon Goth, Ilyes Mnassri-Cetim


A Gerotor pump is composed of an external and internal gear with conjugate cycloidal profiles. From suction to delivery ports, the fluid is transported inside cavities formed by teeth and driven by the shaft. From a geometric and conceptional side it is worth to note that the internal gear has one tooth less than the external one. Simcenter Amesim v.16 includes a new submodel for modelling the hydraulic Gerotor pumps behavior (THCDGP0). This submodel considers leakages between teeth tips using Poiseuille and Couette flows contributions. From the 3D CAD model of the studied pump, the “CAD import” tool takes out the main geometrical characteristics and the submodel THCDGP0 computes the evolution of each cavity volume and their relative position according to the suction or delivery areas. This module, based on international publications, presents robust results up to 6 000 rpm for pressure greater than atmospheric level. For higher rotational speeds or lower pressures, oil aeration and cavitation effects are significant and highly drop the pump’s performance. The liquid used in hydraulic systems always contains some gas, which is dissolved in the liquid at high pressure and tends to be released in a free form (i.e. undissolved as bubbles) when pressure drops. In addition to gas release and dissolution, the liquid itself may vaporize due to cavitation. To model the relative density of the equivalent fluid, modified Henry’s law is applied in Simcenter Amesim v.16 to predict the fraction of undissolved gas or vapor. Three parietal pressure sensors have been set up upstream from the pump to estimate the sound speed in the oil. Analytical models have been compared with the experimental sound speed to estimate the occluded gas content. Simcenter Amesim v.16 model was supplied by these previous analyses marks which have successfully improved the simulations results up to 14 000 rpm. This work provides a sound foundation for designing the next Gerotor pump generation reaching high rotation range more than 25 000 rpm. This improved module results will be compared to tests on this new pump demonstrator.

Keywords: High Speed, Simulations, cavitation, aeration, aeronautic, gerotor pump

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[1] Gamez-Montero P-J., Codina E., Castilla R., “A Review of Gerotor Technology in Hydraulic Machines”, Energies. 12 (2019), 2423
[2] Buono D., Schiano di Cola F.D., Senatore A., Frosina E., Buccilli G., Harrison J., “Modelling approach on a Gerotor pump working in cavitation conditions”, Energy Procedia 2016, 101, 701–709.
[3] Buono D., Siano D., Frosina E., Senatore A., “Gerotor pump cavitation monitoring and fault diagnosis using vibration analysis through the employment of auto-regressive-moving-average technique” Simul. Model. Pract. Theory 2017, 71, 61–82.
[4] Shah Y.G., Vacca A., Dabiri S., Frosina E., “A fast lumped parameter approach for the prediction of both aeration and cavitation in Gerotor pumps. Meccanica 2017, 53, 175–191.
[5] Pellegri M., Vacca, M., Frosina E., Buono D., Senatore, A., “Numerical analysis and experimental validation of Gerotor pumps: A comparison between a lumped parameter and a computational fluid dynamics-based approach”, Proc. Inst. Mech. Eng. C 2016, 231, 4413–4430.
[6] Pellegri M., Vacca A., Devendran R., Dautry E., Ginsberg B., “A Lumped Parameter Approach for GEROTOR Pumps: Model Formulation and Experimental Validation”, In Proceedings of the 10th International Fluid Power Conference, Dresden, Germany, 8–10 March 2016.
[7] Singh R., Salutagi S.S., Piotr P., Madhavan J., “Study of Effect of Air Content in Lubrication Oil on Gerotor Pump Performance Using CFD Simulations”, SAE Technical Papers 2019-26-0300, SAE International: Warrendale, PA, USA, 2019, pp. 1–5.
[8] Baran B., and Chen, W., “Assessing the Windage Tray Blockage Effect on Aeration in the Oil Sump”, SAE Technical Paper 2007-01-4109.
[9] Ippoliti L., Steime, J., Hendrick P., “Investigation on an Oil Aeration Measurement Technique for the Study of Pump Performance in an Aircraft Engine Lubrication System”, Proceedings of the ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. Volume 5C: Heat Transfer, 2015.
[10] Ippoliti L., Vincké J., Hendrick P., “Oil Aeration and Degassing Measurements for the Study of Aero-Engine Oil Pump Performance in Cavitation”, Proceedings of the ASME 2017 Fluids Engineering Division Summer Meeting, Volume 1A, Symposia, 2017.
[11] Rundo M., Squarcini R., Furno F., “Modelling of a Variable Displacement Lubricating Pump with Air Dissolution Dynamics”, SAE Int. J. Engines 11(2):2018.
[12] DSi, “Air-X – On-line Lubricant Aeration – Technical Brochure”, 2018
[13] Zhou J., Vacca A., Manhartsgruber B., “A Novel Approach for the Prediction of Dynamic Features of Air Release and Absorption in Hydraulic Oils”, ASME. J. Fluids Eng. September 2013; 135(9): 091305.
[14] Kratschun F., Schmitz K., Murrenhoff, H., “Experimental investigation of the Bunsen and the Diffusion coefficients in hydraulic fluids”, 10th International Fluid Power Conference, March 8 - 10, 2016, Vol. 1, pp. 181-192.
[15] Margolis D.L., Brown F.T., “Measurement of the propagation of long-wavelength disturbances trough turbulent flow in tubes,” J Fluids Eng, pp. 70–78, 1976.
[16] Jakobsen J.K., “On the mechanism of head breakdown in cavitating inducer”. J Basic Eng Trans ASME 291–305, 1964.
[17] Resler E.L, “Characteristics and sound speed in nonisentropic gas flows with nonequilibrium thermodynamic states”. Journal of the Aeronautical Sciences, 24(11), 785-790, 1957.
[18] R. Sedney, J.C South, and N Gerber, and U.S. Army Ballistic Research Laboratory “Characteristic Calculation of Non-equilibrium Flows”, Ballistic Research Laboratories, 1962
[19] Henry W., “Experiments on the quantity of gases absorbed by water, at different temperatures, and under different pressures”, Philosophical Transactions of the Royal Society of London, vol. 93,‎ p. 29–274, 1803.
[20] Gamez-Montero P.J.; Codina E.; Castilla R., “A Review of Gerotor Technology in Hydraulic Machines”, Energies 2019, 12, 2423.
[21] Gamez-Montero P.J., Castilla R., Del Campo D., Ertürk N., Raush R., Codina E., “Influence of the interteeth clearances on the flow ripple in a gerotor pump for engine lubrication”, Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 2012 226: 930.
[22] Garcia-Vilchez M., Gamez-Montero P., Codina, E., Castilla R., Raush G., Freire V., Francisco J., Ri, C., “Computational fluid dynamics and particle image velocimetry assisted design tools for a new generation of trochoidal gear pumps”, Advances in Mechanical Engineering. 7, 2015.
[23] Castilla, R., Gamez-Montero, P. J., Raush, G., and Codina, E., “Method for Fluid Flow Simulation of a Gerotor Pump Using OpenFOAM”, ASME. J. Fluids Eng. November 2017.
[24] Siemens PLM, “LMS Imagine.Lab AMESim Thermal-Hydraulic Component Design Manual”, 2017.
[25] Fabiani, M., Mancò, S., Nervegna, N., Rundo, M. et al., "Modelling and Simulation of Gerotor Gearing in Lubricating Oil Pumps", SAE Technical Paper 1999-01-0626, 1999.
[26] Mancò S., Nervegna N., Rundo M., Armenio G., Pachetti C., Trichilo R. “Gerotor Lubricating Oil Pump for IC Engines”, SAE Transactions - Journal of Engines (1998). 107. 2267-2283.
[27] Ivanovic L., Josifovic D., Blagojevic M., Stojanovic B., Ilic A., “Determination of gerotor pump theoretical flow”, COMETa, 2012.
[28] Rundo M., “Models for Flow Rate Simulation in Gear Pumps: A Review”, In: ENERGIES, vol. 10 n. 9 (2017), 1261, - ISSN 1996-1073.