It is known, that track deterioration (loss of its geometry) strongly depends on track support conditions, particularly on the ballast. In this paper a novel approach is presented to predict the evolution of track vertical irregularities due to vehicle-track dynamic interaction taking into account ballast stiffness with dry friction. An applied vehicle-track model is composed of a railway car a...

Present cable trolley brakes used in material transfer or overhead trolley transport systems uses twin shoe caliper brakes operated by solenoid. These brakes are not fail safe, means that slip occurs between cable and brake caliper. Sometimes overloading leads to wear of brake shoe material. The failure of brake system may increase the chances to loss of life of occupant. These conventional cal...

We show that two basic mechanical processes, the collision of particles and rolling motion of a sphere on a plane, are intimately related. According to our recent findings, the restitution coefficient for colliding spherical particles ǫ, which characterizes the energy loss upon collision, is directly related to the rolling friction coefficient μroll for a viscous sphere on a hard plane. We quan...

Artificial collisions during particle tracking with selfconsistent space charge lead to diffusion-like, numerical effects. The artificial collisions generate a stochastic noise spectrum. As a consequence the entropy and the emittance can grow along periodic focusing structures. The growth rates depend on the number of simulation macro-particles and on the space charge tune shifts. For long-term...

This article describes the physics of superoleophobic surfaces, combining a recently developed free-energy approach and finite element modeling. We start by investigating the peculiar wetting behavior of such surfaces, originating in their “re-entrant” geometry, and discussing a specific mechanism for the “filling transition”, leading to the loss of superoleophobicity. We then focus on their fr...

I N T R 0 D U C T I 0 N In recent years, the application of double-flow rotary vane compressor in automotive air-conditioning systems has been increased because of its multiple cylinder characteristic. A certain problem is its high friction loss at higher speeds. The greatest amount of the friction is caused by the lubrication systems between the vane tip and the cylinder wall and between vane ...

Friction decoupling, i.e. the computation of friction vector components making separate use corresponding velocity components, is common in staggered grid models SWE simplifications (Zero-Inertia and Local Inertia Approximation), due to programming simplicity consequent calculations speed-up. In present paper, effect decoupling has been studied from theoretical numerical point view. First, it f...

Plasma electrolytic boriding (PEB) is a method of combination surface strengthening and surface texturing on metal. In this study, the kinetics and the lubrication friction of borided layers in the plasma electrolytic boriding on the Q235 were investigated in an aqueous solution for 5–15 min. The cross-section and surface morphologies of the boriding layers were confirmed using scanning electro...

One of the great enemies of rubber compounds is heat. Heat will cause chemical and physical degradation of vulcanized rubber as well as a considerable loss in its strength. A major source of heat generation in a tire is due to internal friction resulting from the viscoelastic deformation of the tire as it rolls along the road. Another source of heat generation in a tire is due to its contact fr...