三种常用油液污染度表示法之间关系的理论研究

理论推导了油液固体污染颗粒粒度概率密度、污染颗粒数量、ISO 4406污染度、NAS 1638固体颗粒污染度及污染颗粒质量之间的关系。算例表明，在常见污染范围里，油液的ISO 4406污染度与NAS 1638固体颗粒污染度之间近似呈线性关系；NAS 1638固体颗粒污染度随油液中固体污染物质量的增加而增加，两者大体呈指数关系。

Theoretical Investigation on Relation between Three Normal Oil Contaminating Levels

Mathematical relations between the probability density distribution of dimension and total number of solid contamination particles,the ISO 4406 and NAS 1638 contaminating levels and mass of solid contaminants in oil were deduced.It shows that in the common oil contamination situation,the NAS 1638 solid particle contaminating level is approximately directly proportional to the contaminating level represented by ISO 4406,NAS 1638 solid particle contaminating level increases with mass of the contamination particles and on the whole there exits a linear relation between them.