Abstract
Keywords - Pilot injection, Post injection, Common-rail Diesel Engine, Lubrication/Piston, Piston Friction Loss
Supercharge and multiple fuel injections are advanced aggressively for the purpose of a diesel engine, high power and low exhaust emissions and low noise. However, we are understand that supercharge and the multiple fuel injections deteriorate piston lubrication state, and it is necessary to advance to the improvement of lubrication at the same time. The fuel injected through multiple injections in a common rail type diesel engine adheres to the cylinder wall and mixes with the lubricating oil around when the piston reaches the top dead center. There is a risk that this could result in worsening the piston lubricating conditions. The aim of this study is to verify the variations in piston lubrication when multiple injections and supercharging are used in a common rail diesel engine with floating liner which is able to measure the piston friction force. Furthermore to compare the overall amount of fuel adhering to the cylinder, the LIF method was used. The findings obtained by the above are as described below.