REVISION TO THE CONCEPT OF EQUILIBRIUM CONCENTRATION OF PARTICLES IN LUBRICATION SYSTEM OF MACHINES

This paper analyzed the numerical characteristics of distribution func tion of particles concentration in oil cycle system of machines by sol ving the stochastic differential equation, then revised the concept of equilibrium concentration of particles and put forward a new concept- stationary concentration. It is proven that the particle concentration in a machine tends towards a wide-stationary process from a non-stati onary process in the condition that the running parameters are constan t and the white noise is introduced as a random component. The statist ics histogram of data distribution obtained by on-line ferrograph show ed different distributions depending on whether running parameters are varied or constant, and it confirms the theoretical analysis. Eventua lly, a new oil sampling concept is advanced for oil condition monitori ng and ferrography. That is oil sampling should be on-line sampling or of larger volume (>100 mi) for off-line sampling in order to get the time mean and space mean. (C) 1998 Elsevier Science S.A.