Achievements and problem of the Lubrication Theory of Machines

摘要

The founder of the Hydrodynamic Lubrication Theory is Petrov Nickolay Pavlovich. In 1883 he received the famous formula for circular cylindrical bearings that determines losses on friction in the lubrication layer. In contemporary editions the Petrov's formula is commonly represented as follows: f=πυμ/ρδ here f - the friction coefficient; υ - the sliding speed m/s; μ - dynamic viscidity lubrication coefficient, Pa; ρ - radial clearance m; δ - R-r, where R, r - correspondently the radiuses of the bearing, arbor, m.. N.P. Petrov considered that the tribosystem tenon-bearing is alignment, the regular cylindrical shape and dimensions of which are not changed under the load. After N.P. Petrov this task was being solved by Osborn Reynolds (England) who like Petrov considered the system quasi-stiff. But apart from Petrov he accepted the eccentric position of tenon in the arbor. Equations gained by O. Reynolds and calculation dependences for plain bearing allowed to determine the main working parameters of bearing: loading capability, losses on friction, the expense of lubrication, minimal thickness of the lubrication layer. Received by Petrov solution for determination of the losses on friction was the special case of Reynolds' solution. With this reason as it was determined before the first half of XX century in the Lubrication Theory of Machines dominated the Reynolds' equation. In it's fullest the Reynolds' solution was used in the book by M.V. Korovchinsky "Theoretical grounds of work of plain bearings", Mashgiz, Moscow, 1959, p. 403.