16. Applications of Tribology on Engine Performance

The improvement of engine efficiency has been of utmost necessity for automobile industries in order to control the increasing climate change and greenhouse emissions. Hence, the fuel efficiency may be increased by minimizing the energy losses from the engine. In spite of wide applications of reciprocating internal combustion (IC) engines in most of the ground and sea transport vehicles and electrical power generations, they have several shortcomings. The IC engines possess low thermal and mechanical efficiencies due to increased loss of fuel energy as heat and friction. They also release a substantial amount of particulate and NO_x (nitrogen oxide) emissions that gives rise to greenhouse effect. Amongst the various approaches of improving engine efficiency, the tribologists and lubrication engineers focused mainly on reduced engine friction as a vital and economic method. The achievement of efficient lubrication of moving engine components with least or no unfavorable effect on the environment is important to lessen friction and wear. The improvements in different tribological engine components and additives may lead to reduced fuel consumption, exhaust emissions and maintenance along with increased engine power outputs and durability. The tribological performance of an engine can be improved by employing materials of superior tribological properties for manufacturing different mechanical parts, improved surface coatings as well as developed lubrication technologies. This chapter presents the details of various components of reciprocating IC engines as well as the lubricants used and the remedial measures to reduce the engine wear and friction.