Durability and lube oil contamination study on diesel engine fueled with various alternative fuels: A review

Abstract

ABSTRACT Alternative fuel research has been gaining more attention by many engine researchers for the past few decades because of the tremendous increase in the demand for the fuel as well as the price of the fuel. Many alternative fuels have been synthesized for diesel engine from sources such as bio feed stocks, waste oils, waste tier scraps, and waste plastics. Most researchers have carried out their research on analyzing the performance, emission, and combustion characteristics of the engine fueled with different alternative fuels. Depending on the characteristics study for a particular alternative fuel, some alterations have been attempted in injection timing, injection pressure, compression ratio, and allowing exhaust gas recirculation (EGR). Moreover, those studies were carried out for only a few times of engine runs. Beyond this, very few researchers conducted experiments on engine parts durability while the engine is powered alternative fuels. This review mainly focuses on tribological study on different engine parts and metals contamination in lubricating crank case oil after the engine has been run for particular hours with alternative fuels. Most of the long durability tests concluded that viscosity of lubricating oil reduced as much earliest, there were increased metal particles in the lubricating oil, slight increased wear in crank case bearing, and increased accumulation of lacquer and carbon on piston compared to diesel operations. Unusual wear could be noticed in pistons, cylinder head, and intake and exhaust valves with alternative fuels. Also, it had induced more dry deposits on fuel injector tip, intake valves, and exhaust valves. In this review, no technical issues have been identified in engine operations, but duration of effective usage of lubricating oil has been reduced by 2/4th time, while reliability of engine parts has been reduced by 1/4th time.