textAs emissions regulations become more stringent and fuel prices increase at a
significant rate, the fuel efficiency of piston engines becomes more important than ever.
Since most of the engine’s friction losses are from the piston/ring assembly, it is
indispensable to reduce the piston/ring assembly friction for better fuel economy. The
Rotating Liner Engine (RLE) was developed to remove the boundary lubrication of the
piston/ring assembly friction through cylinder liner rotation.
Even though the RLE was initially developed mainly by Dr. Dardalis several
years ago, the friction reduction effect of the RLE was not confirmed except via
preliminary motoring tests using a crude dynamometer. The main purpose of this
dissertation is to confirm the RLE effect on piston assembly friction reduction using
sophisticated measurement methods. Three different friction measurement methods were
applied in measuring the friction force difference between a baseline engine and a
prototype RLE. Through the use of three different friction measurement methods, the
friction reduction of the RLE has been confirmed via this dissertation research and each
of the friction measurement methods is also compared based on its measurement results.
The analysis of the friction mechanism of the baseline engine was performed using the
instantaneous IMEP method and a commercial simulation program called RINGPAK.
Through the use of experimental methods and the simulation, the friction mechanism of
the piston/ring assembly is analyzed. The limitation of the experimental and the
calculation methods is also discussed.Mechanical Engineerin