In gearboxes, the transmission of power and motion is accompanied by power losses. Load-independent power losses are particularly relevant at higher circumferential speeds. In the literature, load-independent power losses are classified according to their phenomenological characteristics. The identified types of interaction include churning, windage, squeezing, and impulse. This work employs an experimental and numerical investigation of a dip-lubricated gearbox to characterize the physical mechanisms of load-independent power loss. The gearbox oil flow, the wetting of the gear surface, and pressure and viscous forces acting on the gear surface are investigated and linked to each other. In this manner, the interaction types, churning, windage, and their transitions, are classified based on their physical characteristics.
ISO/TR 18792:2008. Lubrication of industrial gear drives.
2.
WalterPLangenbeckK. Anwendungsgrenzen für die Tauchschmierung von Zahnradgetrieben; Plansch- und Quetschverluste bei Tauchschmierung: Forschungsheft 118/1982, Frankfurt am Main, 1982.
3.
NeurouthAChangenetCVilleF, et al.Experimental investigations to use splash lubrication for high-speed gears. J Tribol2017; 139: 61104: https://doi.org/10.1115/1.4036447
4.
MaurerJ. Lastunabhängige Verzahnungsverluste schnellaufender Stirnradgetriebe. Dissertation, Universität Stuttgart. Stuttgart, 1994.
MarchesseYChangenetCVilleF. Drag power loss investigation in cylindrical roller bearings using CFD approach. Tribol Trans2019; 62: 403–411. https://doi.org/10.1080/10402004.2018.1565009
9.
FeldermannAFischerDNeumannS, et al.Determination of hydraulic losses in radial cylindrical roller bearings using CFD simulations. Tribol Int2017; 113: 245–251. https://doi.org/10.1016/j.triboint.2017.03.020
10.
HildebrandLLiuHPascholdC, et al.Classification of numerical, experimental, and analytical approaches for gearbox oil flow and no-load gear power loss. Eng Sc Techno, Int J2024; 53: 101661. https://doi.org/10.1016/j.jestch.2024.101661
HildebrandLGenuinSLohnerT, et al.Numerical analysis of the heat transfer of gears under oil dip lubrication. Tribol Int2024; 195: 109652. https://doi.org/10.1016/j.triboint.2024.109652
16.
HildebrandLBeiererPLohnerT, et al.Numerical calculation of the oil flow in a truck rear axle transmission and the influence of gear-induced air flow. J Tribol2024; 146: 114602. https://doi.org/10.1115/1.4065872
17.
ConcliFGorlaCDella TorreA, et al.Windage power losses of ordinary gears: different CFD approaches aimed to the reduction of the computational effort. Lubricants2014; 2: 162–176. https://doi.org/10.3390/lubricants2040162
18.
AndersonNELoewenthalSH. Spur-gear-system efficiency at part and full load. NASA Technical Paper 1622, 1980.
19.
LiuHJurkschatTLohnerT, et al.Detailed investigations on the oil flow in dip-lubricated gearboxes by the finite volume CFD method. Lubricants2018; 6: 47. https://doi.org/10.3390/lubricants6020047
HildebrandLDanglFSedlmairM, et al.CFD Analysis on the oil flow of a gear stage with guide plate. Forsch Ingenieurwes2021; 30: 285. https://doi.org/10.1007/s10010-021-00523-5
22.
ChangenetCLeprinceGVilleF, et al.A note on flow regimes and churning loss modeling. J Mech Des2011; 133: 13. https://doi.org/10.1115/1.4005330
23.
QuibanRChangenetCMarchesseY, et al.Experimental investigations about the power loss transition between churning and windage for spur gears. J Tribol2021; 143: 205. https://doi.org/10.1115/1.4047949
24.
DiabYVilleFVelexP, et al.Windage losses in high speed gears—preliminary experimental and theoretical results. J Mech Des2004; 126: 903–908. https://doi.org/10.1115/1.1767815
25.
TerekhovAS. Hydraulic losses in gearboxes with oil immersion. Russ Eng J1975; 55: 7–11.
26.
LausterE. Untersuchungen und Berechnungen zum Wärmehaushalt mechanischer Schaltgetriebe. Zugl.: Stuttgart, Univ., Diss., 1980. Stuttgart: Inst. für Maschinenelemente und Gestaltungslehre, 1980.
27.
SeetharamanSKahramanA. Load-Independent spin power losses of a spur gear pair: model formulation. Proc Inst Mech Eng Part J: J Eng Tribol2009; 131: 22201. https://doi.org/10.1115/1.3085943
28.
StreeterVLWylieEB. Fluid mechanics. 8. ed. New York: McGraw-Hill, 1985.
PallasSMarchesseYChangenetC, et al.A windage power loss model based on CFD study about the volumetric flow rate expelled by spur gears. Mech Ind2012; 13: 317–323. https://doi.org/10.1051/meca/2012028
31.
VoeltzelNMarchesseYChangenetC, et al.On the influence of helix angle and face width on gear windage losses. Proc Inst Mech Eng, Part C: J Mech Eng Sci2016; 230: 1101–1112. https://doi.org/10.1177/0954406215602036
32.
SeetharamanSKahramanA. A windage power loss model for spur gear pairs. Tribol Trans2010; 53: 473–484. https://doi.org/1080/10402000903452848
33.
LaruelleSFossierCChangenetC, et al.Experimental investigations and analysis on churning losses of splash lubricated spiral bevel gears. Mech Ind2017; 18: 412. https://doi.org/10.1051/meca/2017007
34.
ShoreJFKolekarASRenN, et al.An investigation into the influence of viscosity on gear churning losses by considering the effective immersion depth. Tribol Trans2023; 66: 906–919. https://doi.org/10.1080/10402004.2023.2247041
35.
WeiCWuWHouX, et al.Research on flow pattern of low temperature lubrication flow field of rotating disk based on MPS method. Tribol Int2023; 180: 108221. https://doi.org/10.1016/j.triboint.2023.108221
MastroneMNConcliF. CFD Simulation of grease lubrication: analysis of the power losses and lubricant flows inside a back-to-back test rig gearbox. J Non-Newtonian Fluid Mech2021; 297: 104652. https://doi.org/10.1016/j.jnnfm.2021.104652
39.
StemplingerJ-P. Tragfähigkeit und Wirkungsgrad von Stirnradgetrieben bei Schmierung mit hochviskosen Fluiden und Fetten NLGI 0, 1 und 2. Zugl.: München, Techn. Univ., Diss., 2013. Ingenieurwissenschaften FZG 192/2013, München, 2013.
ChernorayVJahanmiriM. Experimental study of multiphase flow in a model gearbox. In: MammoliAABrebbiaCA (eds) Computational methods in multiphase flow VI. Kos, Greece: WIT PressSouthampton, UK, 15.06.2011 - 17.06.2011, pp.153–164.
42.
LukePOlverAV. A study of churning losses in dip-lubricated spur gears. Proc Inst Mech Eng Part G: J Aerosp Eng1999; 213: 337–346. https://doi.org/10.1243/0954410991533061
43.
LiuHArfaouiGStanicM, et al.Numerical modelling of oil distribution and churning gear power losses of gearboxes by smoothed particle hydrodynamics. Proc Inst Mech Eng Part J: J Eng Tribol2019; 233: 74–86. https://doi.org/10.1177/1350650118760626
44.
MastroneMNHartonoEAChernorayV, et al.Oil distribution and churning losses of gearboxes: experimental and numerical analysis. Tribol Int2020; 151: 106496. https://doi.org/10.1016/j.triboint.2020.106496
45.
VárhegyiZKristófG. Mass flux distribution measurements and visualizations of a fluid sheet generated by a partially immersed dip-lubricated gear. Period Polytech Mech Eng2016; 60: 66–81. https://doi.org/10.3311/PPme.7764
46.
HildebrandLDanglFPascholdC, et al.CFD Analysis on the heat dissipation of a dry-lubricated gear stage. Appl Sci2022; 12: 10386. https://doi.org/10.3390/app122010386
47.
ZhouCJiangXSuJ, et al.Injection lubrication for high-speed helical gears using the overset mesh method and experimental verification. Tribol Int2022; 173: 107642. https://doi.org/10.1016/j.triboint.2022.107642
48.
MastroneMNHildebrandLPascholdC, et al.Numerical and experimental analysis of the oil flow in a planetary gearbox. Appl Sci2023; 13: 1014. https://doi.org/10.3390/app13021014
49.
Al-ShiblKSimmonsKEastwickCN. Modelling windage power loss from an enclosed spur gear. Proc Inst Mech Eng Part A: J Power Energy2007; 221: 331–341. https://doi.org/10.1243/09576509JPE344
HillMJ. A computational investigation of gear windage. Dissertation, The Pennsylvania State University, 401 Old Main, PA 16802, 2010.
52.
HillMJKunzRFMedvitzRB, et al.CFD analysis of gear windage losses: validation and parametric aerodynamic studies. J Fluids Eng2011; 133. https://doi.org/10.1115/1.4003681
53.
MassiniDFondelliTAndreiniA, et al.Experimental and numerical investigation on windage power losses in high speed gears. J Eng Gas Turbines Power2018; 140. https://doi.org/10.1115/1.4038471
54.
SchedlU. Einfluß des Schmierstoffs auf die Grübchenlebensdauer einsatzgehärteter Zahnräder. Dissertation, Technische Universität München, 1998.
55.
BobzinKBagcivanNGoebbelsN, et al.Lubricated PVD CrAlN and WC/C coatings for automotive applications. Surf Coat Technol2009; 204: 1097–1101. https://doi.org/10.1016/j.surfcoat.2009.07.045
LucyLB. A numerical approach to the testing of the fission hypothesis. Astron J (N Y)1977; 82: 1013. https://doi.org/10.1086/112164
58.
GingoldRAMonaghanJJ. Smoothed particle hydrodynamics: theory and application to non-spherical stars. Mon Not R Astron Soc1977; 181: 375–389. https://doi.org/10.1093/mnras/181.3.375
59.
ShadlooMSOgerGLe TouzéD. Smoothed particle hydrodynamics method for fluid flows, towards industrial applications: motivations, current state, and challenges. Comput Fluids2016; 136: 11–34. https://doi.org/10.1016/j.compfluid.2016.05.029
60.
AdamiS. Modeling and simulation of multiphase phenomena with smoothed particle hydrodynamics. München, Technische Universität München, Diss., 2014, Universitätsbibliothek der TU München. München, 2014.
MastroneMNConcliF. Numerical modeling of fluid’s aeration: analysis of the power losses and lubricant distribution in gearboxes. J Appl Comput Mech2022; 9: 83–94. https://doi.org/10.3390/en15030837
ConstienLWeberMPellkoferJ, et al.Efficiency of bevel and hypoid gears—test rig development and experimental investigations. Machines2024; 12: 647. https://doi.org/10.3390/machines12090647
69.
BassEVimmerL. Bestimmung des leistungsbedarfs beim rühren. Period Polytech Mech Eng1962; 6: 263–276.
70.
WanZYangSWangH. Multiphase stirring dynamics of gas-slag-matte in large-scale Side-blown copper bath smelting process. J Sustain Metall2024; 10: 992–1006. https://doi.org/10.1007/s40831-024-00841-2
