Wyniki wyszukiwania - BazTech

1

Pressure and velocity distribution in slide journal bearing lubricated micropolar oil

Krasowski P.

Journal of Polish CIMAC

|

2010

|

Vol. 5, no 1

119-126

EN

This paper shows results of numerical solutions an modified Reynolds equations for laminar unsteady oil flow in slide journal bearing gap. Laminar unsteady oil flow is performed during periodic and unperiodic perturbations of bearing load or is caused by the changes of gap height in time. During modelling crossbar bearing operations in combustion engines, bearing movement perturbations from engine vertical vibrations causes velocity flow perturbations of lubricating oil on the shaft in the circumferential direction. This solution example apply to isothermal bearing model with infinity length. Lubricating oil used in this model has Newtonian properties and constant dynamic viscosity. Results are presented in the dimensionless hydrodynamic pressure and tangential tension distribution diagrams. Diagrams also presents capacity and friction force change during the time of velocity perturbations. Received solutions were compared with the solution received by the stationary lubrication flow in the slide journal bearing, which were made with the same parameter assumption by constant dynamic oil viscosity. Isothermal bearing model is similar to friction node model by steady-state heat load conditions. Described effect can be used as on example of modeling the bearing friction node operations in reciprocating movement during exploitation of engines and machines.

2

Capacity and friction force in slide journal bearing gap by laminar unsteady lubrication

Krasowski P.

Journal of KONES

|

2010

|

Vol. 17, No. 3

231-238

EN

This paper shows results of numerical solutions modifled Reynolds equations for laminar unsteady oil flow in slide Journal bearing gap. Laminar unsteady oil flow is performed during periodic and unperiodic perturbations of bearing load or is caused by the changes of gap height in time. During modelling crossbar bearing operations in combustion engines, bearing movement perturbations from engine vertical vibrations causes velocity flow perturbations of lubricating oil on the bearing race and on the bearing slider in the circumferential direction. Above perturbations occur mostly during the starting and stopping of machine. This solution example applies to isothermal bearing model with infinity length. Lubricating oil used in this model has Newtonian properties and constant dynamic viscosity. Results are presented in the dimensionless hydrodynamic pressure and tangential tension distribution diagrams. Diagrams also presents capacity and friction force change during the time ofvelocity perturbations. Received solutions were compared with the solution received by the stationary lubrication flow in the slide Journal bearing, which were made with the same parameter assumption by constant dynamie oil viscosity. Isothermal bearing model is similar to friction node model by steady-state heat load conditions. Described effect can be used as on example of modelling the bearing friction node operations in reciprocating movement during exploitation of engines and machines.

3

Zredukowany współczynnik tarcia w poprzecznym łożysku ślizgowym

Krasowski P.

Zeszyty Naukowe / Wyższa Szkoła Morska w Szczecinie

|

2003

|

nr 71

223-232

PL

Przedstawiono metodę analityczną wyznaczania zredukowanego współczynnika tarcia w poprzecznym łożysku ślizgowym. Prezentowane rozważania dotyczą łożyska wodzikowego silnika spalinowego. Wykorzystano rozwiązanie analityczne równania Reynoldsa dla łożyska o nieskończonej szerokości smarowanego olejem o stałej lepkości. Wyznaczone ciśnienie, naprężenie styczne oraz siły nośności, siły tarcia i współczynnik tarcia przedstawiono w postaci bezwymiarowej.

EN

The present paper shows an analytic method of marking a modified friction coefficient in slide bearing. The considerations refer to crosshead bearing in the internal combustion engine. One used analytic solution of Reynolds equation for bearing of infinite breadth lubricated with oil of constant viscosity. The determined pressure, tangent tension, capacity force, friction force and the modified friction coefficient were represented in dimensionless form.