EXPERIMENTAL INVESTIGATION OF THE VALVETRAIN FRICTION IN ACTUAL ENGINE OPERATION CONDITIONS
Recently, the demands for improved fuel economy have been continually rising because of environmental protection policies, legislative pressures on emissions and increases in the price of oil. Reducing the friction power loss in a production engine may be regarded as one of the most effective technologies for improving fuel economy because the technology is cost effective and applicable to a great number of vehicles. This paper describes attempts to measure the torque needed to drive a camshaft and to examine the sources of the torque fluctuations in order to analyze the friction in valvetrains. The measurements were performed through a cam sprocket-type torquemeter, which was able to measure the torque of the valvetrain under actual engine operating conditions. In the cam torque measured, the fluctuations were mainly dependent on the primary oscillations caused by cam events and the secondary oscillations caused by the valvetrain natural frequency. The range of the fluctuations became greater at high speed because of the inertial mass. The resulting FMEP (friction mean effective pressure) of the valvetrain decreased, and the effective peak tension increased with an increase in the engine speed.
- Baniasad, S. M. and Emes, M. R. (1998). Design and development of method of valve-train friction measurement. SAE Paper No. 980572.
- Crane, M. E. and Meyer, R. C. (1990). A process to predict friction in an automotive valve train. SAE Paper No. 901728.
- Fawcett, J. N. (1999). Improvements in belt tension setting procedures on internal combustion engines. Proc. Institution of Mechanical Engineers, 213, Part D, J. Automobile Engineering, 119？126.
- Gangopadhyay, A., Soltis, E. and Johnson, M. D. (2004). Valvetrain friction and wear: Influence of surface engineering and lubricants. Proc. Institution of Mechanical Engineers, 218, Part J, J. Engineering Tribology, 147？ 156.
- Heywood, J. B. (1988). Internal Combustion Engine Fundamentals. Int. Edn. McGraw-Hill. Singapore.
- Kang, S., Kauh, S. K. and Ha, K. (2007). Measurement of the torque for driving cam shaft in real engine enviroments. Trans. KSME (B) 31, 3, 242？247.
- Kim, D. J. and Nguyen, V. T. (2007). Reduction of high frequency excitations in a cam profile by using modified smoothing spline curves. Int. J. Automotive Technology 8, 1, 59？66.
- Lee, J. (2007). A Study on In-vehicle Torque Measurement of an Engine and Engine Accessories Using Bluetooth. Ph.D. Dissertation. School of Mechanical and Aerospace Engineering. Seoul Nat'l University. Seoul. Korea.
- Oh, K., Plauman, M., Romanick, J., Farmer, I., Aimone, M. and Barnaby, D. (2001). performance comparison between chain and belt cam-drive systems. SAE Paper No. 2001-01-0365.
- Teodorescu, M., Taraza, D., Henein, N. A. and Bryzik, W. (2002). Experimental analysis of dynamics and friction in valve train systems. SAE Paper No. 2002-01-0484.
- Weber, C., Herrmann, W. and Stadtmann, J. (1998). Experimental investigation into the dynamic engine timing chain behaviour. SAE Paper No. 980840.
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