The lubrication system of an internal combustion engine is a crucial component that performs a variety of functions, including lowering friction, cooling, supporting the load, and cleaning debris from the engine’s various moving components. Oil aeration refers to the phenomenon of trapping air bubbles in lubricating oil. High oil aeration can have a detrimental effect on engine performance since modern engines are equipped with parts such as VVT, HLA, RFF, PCJ, LCJ, and other components; whose operation is substantially impacted by the amount of air in circulating oil.
In this study, an Inline 4-cylinder NA DOHC gasoline engine was tested with a densimeter-type aeration measuring machine. Test equipment layout which consists of hoses of various diameters and lengths were designed, fabricated, and instrumented to operate under different test conditions. Visual observations and quantitative measurements of oil aeration were performed in the oil sump. The purpose of this study is to evaluate the impact of aeration measurement equipment’s layout on overall oil aeration and how it can be eliminated. Furthermore, the effect of engine speed, oil quantity, oil temperature, and engine running time is also discussed in this study.
According to test results, the equipment used to measure oil aeration, itself makes a significant contribution to total oil aeration. Based on these test results, an experimental methodology has been developed and discussed to minimize oil aeration due to equipment layout.