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Prediction of Overall Efficiency in Multistage Gear Trains

Authors: James Kuria, John Kihiu

Abstract:

A mathematical model for determining the overall efficiency of a multistage tractor gearbox including all gear, lubricant, surface finish related parameters and operating conditions is presented. Sliding friction, rolling friction and windage losses were considered as the main sources of power loss in the gearing system. A computer code in FORTRAN was developed to simulate the model. Sliding friction contributes about 98% of the total power loss for gear trains operating at relatively low speeds (less than 2000 rpm input speed). Rolling frictional losses decrease with increased load while windage losses are only significant for gears running at very high speeds (greater than 3000 rpm). The results also showed that the overall efficiency varies over the path of contact of the gear meshes ranging between 94% to 99.5%.

Keywords: Efficiency, multistage gear train, rolling friction, slidingfriction, windage losses.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1076244

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References:


[1] H. Xu and A. Kahraman, "Prediction of Mechanical Efficiency of Parallel - Axis Gear Pairs," Transactions of ASME, vol. 129, pp. 58-68, 2007.
[2] J. H. Kuang and A. D. Lin, "The Effect of Tooth Wear on the Vibration Spectrum of a Spur Gear Pair," Journal of Vibrations and Acoustics, vol. 123, pp. 311-317, 2001.
[3] M. Vaishya and R. Singh, "Strategies for Modeling Friction in Gear Dynamics," Journal of Mechanical Design, vol. 125, pp. 383-393, 2003.
[4] N. E. Anderson and S. H. Loewenthal, "Efficiency of Non-Standard High Contact Ratio Involute SpurGears," Tech Rep., NASA Lewis Research Center, 1984.
[5] R. F. Handschuh and C. J. Kilmain, "Preliminary comparison of experimental and analytical efficiency results of high-speed helical gear trains," Tech. Rep., NASA Lewis Research Center, 2003.
[6] P. Heingartner and D. Mba, "Determining Power Losses in the Helical Gear Mesh," Gear Technology, pp. 32-37, 2005.
[7] J. K. Kimotho, "Modeling and simulation of vibrations of a multistage tractor gearbox," Master-s thesis, Jomo Kenyatta University of Agriculture and Technology, 2008.
[8] P. Dawson, "High speed gear windage," GEC Review, vol. 4, no. 3, pp. 164-167, 1988.
[9] H. Cheng, "Isothermal elastohydrodynamic theory for the full range of pressure-viscosity coefficient," Tech. Rep., NASA Lewis Research Center, 1971.
[10] H. Xu, Developement of a generalized Mechanical Efficiency Prediction Methodology for Gear Pairs. Phd Thesis, The Ohio State University, 2005.
[11] Hsiang-Hsi Lin, Computer - Aided Design and Analysis of Spur Gear Dynamics. PhD Thesis, University of Cincinnati, 1985.
[12] K. G. Sejoong Oh and J. R. Barber, "Energy Conserving Equations of Motion for Gear Systems," Journal of Vibrations and Acoustics, Transactions of ASME, vol. 127, pp. 208-212, 2005.
[13] James Kuria and John Kihiu, "Modeling parametric vibration of multistage gear systems as a tool for design optimization," International Journal of Mechanical, Industrial and Aerospace Engineering, vol. 2, no. 3, pp. 159 - 166, 2008.