Energy losses in an internal combustion engine are either thermal or parasitic. The latter are the mechanical inefficiencies, chiefly as the result of generated friction. Nearly half of these losses are attributed to the piston–cylinder system. During idle and at low engine speeds, friction is the major contributor to the overall engine losses. In particular, the rather small top compression ring accounts for a disproportionate share. Therefore, detailed understanding of compression ring tribology/dynamics (referred to as tribodynamics) is essential. Moreover, the ring’s primary sealing function may be breached by its elastodynamic behavior. The reported analyses in literature do not account for the transient nature of ring elastodynamics, as an essential feature of ring–bore tribology. The transient in-plane dynamics of incomplete rings are introduced in the analysis and verified using a finite element analysis (FEA) model, in order to address this shortcoming. The methodology is then coupled with the tribological analysis of the top compression ring. Comparison is made with experimental measurements which show the validity of the proposed method. The radial in-plane elastodynamic response of the ring improves the accuracy of the frictional power loss calculations.
On the Effect of Transient In-Plane Dynamics of the Compression Ring Upon Its Tribological Performance
Contributed by the Structures and Dynamics Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received June 20, 2014; final manuscript received July 4, 2014; published online October 14, 2014. Editor: David Wisler.
- Views Icon Views
- Share Icon Share
- Search Site
Baker, C., Rahmani, R., Theodossiades, S., Rahnejat, H., and Fitzsimons, B. (October 14, 2014). "On the Effect of Transient In-Plane Dynamics of the Compression Ring Upon Its Tribological Performance." ASME. J. Eng. Gas Turbines Power. March 2015; 137(3): 032512. https://doi.org/10.1115/1.4028496
Download citation file: