Computational fluid dynamics is implemented to investigate the influence of the wheel contact patch on the global car aerodynamics. Two main aspects of the problem are the contact step and patch shape. Three important parameters: step height, cut angle, and tire tread shape are taken into consideration. For validations of the numerical results, the experimental data are also considered. The obt...

In this study, a low degree-of-freedom mechanical model of a rolling tire is constructed, in which the lateral deformation of the contact patch and tire carcass is considered. The so-called delayed contact patch model is implemented and combined with a simple tire carcass model. The interaction between the contact patch and the carcass together with the lateral mode of the attached suspension s...

The contact area and pressure distribution in a wheel/rail contact is essential information required in any fatigue or wear calculations to determine design life, re-grinding, and maintenance schedules. As wheel or rail wear or surface damage takes place the contact patch size and shape will change. This leads to a redistribution of the contact stresses. The aim of this work was to use ultrasou...

The results study of the motion along a curvilinear trajectory multi-axle vehicle axle group elastic wheel on ground plane with high coefficient adhesion are presented. is considered as an integral mechanism, which includes hard rim, tire body and large contact patch.The analysis previous studies showed that during movement curved trajectory, rim rotates simultaneously its lateral offset relati...

Wheel wear has been a concern in the railway for several decades. Studying the form change of the wheel/rail contacts in particular railways consisting of sharp curves helps to identify the risk of severe or catastrophic wear to minimize maintenance costs in order to be competitive in the transportation business. In this paper, the wheel/rail contact was studied on the particular railways. The ...

Steering torque is a very important quantity for the driver feeling. In fact, it gives an idea of road adherence condition during driving. Several models have been developed to simulate shear forces at contact patch, most them are based on semi-empirical tire that account slip and angles. They good reliability when speed high enough. At low speed, like in parking, these suffer from both numeric...

a r t i c l e i n f o a b s t r a c t The dynamics of wheel shimmy is studied when the self-excited vibrations are related to the elasticity of the tyre. The tyre is described by a classical stretched string model, so the tyre-ground contact patch is approximated by a contact line. The lateral deformation of this line is given via a nonholonomic constraint, namely, the contact points stick to t...

background: contact dermatitis (cd) is a significant problem among nurses. although there are reports about the prevalence of cd from different parts of the world, data about its frequency in turkey and about allergic contact sensitization among nurses is insufficient. objective: to define the frequency and patterns of allergic contact sensitization and related symptoms in practicing and studen...