... pressure with the consideration of the viscoelasticity of the gear material. Archard’s wear equation is applied to calculate the surface wear depth. Results of the wear experiment of the POM PLGP specimens validated the feasibility of the calculation method. This study provides a necessary basis...

...W. Wayne Chen; Q. Jane Wang; Z. Huan; X. Luo Contact of viscoelastic materials with complicated properties and surface topography require numerical solution approaches. This paper presents a 3-D semianalytical contact model for viscoelastic materials. With the hereditary integral operator...

...Azam Thatte; Richard F. Salant A visco-elastohydrodynamic model of a hydraulic rod seal during transient operation has been developed. The model includes analyses of the macro- and microscale deformation mechanics and contact mechanics, and the microscale fluid mechanics. Viscoelasticity enters...

... are included. The elastic and time rate-dependent portion of force is derived using a viscoelastic interaction of the two asperities. Statistical consideration of rough surfaces then furnishes the mathematical formulation of total normal force due to adhesion, elastic, and rate-dependent properties...

... and the viscoelastic dampers added behind the FPTPGB pads delayed the onset of subsynchronous vibrations (from 43 krpm without damper to above 50 krpm with damper). Midrange subsynchronous vibrations of the destabilized system initiated at ∼ 20 krpm were suppressed by ∼ 25 krpm due to the stabilizing effect of rotor...

... with time depending on the creep properties and the stiffness of the housing. Assessing relaxation is a key parameter in determining the tightness performance of a valve stem packing over time. An analytical model based on the packing viscoelastic behavior is developed to assess the contact pressures...

... irreversible character makes the contact problem more difficult. Furthermore, when one or more of the contacting bodies is made of a viscoelastic material, the problem becomes more complicated. A nonlinear time-dependent contact problem is addressed. The objective of the present work is to develop...

...Osama M. Abuzeid; Peter Eberhard The objective of this study is to construct a continuous mathematical model that describes the frictionless contact between a nominally flat (rough) viscoelastic punch and a perfectly rigid foundation. The material’s behavior is modeled by assuming a complex...

...-to-shoulder contact and viscoelastic asperity behavior, mathematical formulae are derived for normal and tangential components of the contact force that depend not only on the proximity of the two surfaces but also the rate of approach and relative sliding. A statistical approach is forwarded in which...

...Fatin F. Mahmoud; Ahmed G. El-Shafei; Mohamed A. Attia Contact pressure distribution throughout the contact interface has a vital role on the tribological aspects of the contact systems. Generally, contact of deformable bodies is a nonlinear problem. Viscoelastic materials have a time-dependent...

... system. This is accomplished by a viscoelastic account of interaction at the micron scale, its statistical quantification through the approximate analytical representation of the statistical expectation of contact force and the introduction of the contact force into the macroscale dynamics of the two...

...Rong Zhang; Xueming He; Simon X. Yang; Xinkai Li There are many studies on variations of the Maxwell model. Tichy (1996) discussed an admissible formulation of the Maxwell viscoelastic fluid model using a convected derivative and applied it to two-dimensional lubrication flow. Tichy obtained...

... 2005 lubrication liquid films elastodynamics shear deformation hydrodynamics lubricants rheology viscoelasticity Liquid lubricants in elastohydrodynamic lubrication (EHL) are subjected to high pressures of the magnitude of 10 9   N / m 2   GPa . Under...

...Satoru Kaneko, Professor; Takemi Tanaka; Satoru Abe; Takuya Ishikawa The squeeze-film effect between a porous rubber surface and a rigid surface has been investigated as a problem of viscoelastic hydrodynamic lubrication (VEHL). An axisymmetric continuum model is introduced to estimate the surface...

... ” = coefficient of friction representing Grosch’s data for “dry” friction of rubber on glass v = kinematic viscosity ω = strain frequency in viscoelastic material ω s , ω st = spatial frequency of roughness (scale i ) ω a = spatial frequency...

...Jose´ M. Madiedo; Jose´ M. Franco; Concepcio´n Valencia; Crı´spulo Gallegos This paper deals with modeling the non-linear rheological behavior of lubricating greases at very low shear rates. With this aim, dynamic linear viscoelastic, non-linear stress relaxation, transient and steady-state shear...

...Chao Zhang; H. S. Cheng A transient non-Newtonian THD theory of dynamically loaded journal bearings in mixed lubrication is presented. A mass conserving cavitation is included and shear thinning and viscoelasticity are characterized by the power law and the upper convected Maxwell models...