Abstract: On a test bench with a turbocharged, intercooler and high-speed diesel engine, the effects of various lubricating oils, including poly alpha olefin (PAO)-based fully synthetic lubricant on particle emission were investigated using a DMS500 fast response particle analyzer. The change of particle emission under different engine working loads and speeds was studied. We laid special stress on analyzing the influence of working temperature and ash content of lubricating oil on particle emission. On this basis, the particle emission characteristics of PAO-based lubricating oil under typical working conditions were summarized. The results showed that the total particle emission peak decreases when the engine load increases, and the peak increases when the engine speed increases. For PAO-based lubricating oil, higher working temperature helps reduce the peak value of particle emission. A lower ash content of lubricating oil can lead to a less total particle emission especially under low engine load. The base composition of lubricating oil has significant influence on engine particle emission. PAO-based lubricating oil has excellent particle emission performance at high operating temperature and high engine load.

Key words: diesel engine; fully synthetic lubricating oil; poly alpha olefin (PAO)-based lubricating oil; particle emission