Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: wheel adhesion

Sortuj według:

Ogranicz wyniki do:

Modelling and simulation of adhesion of the rail vehicle

Lewandowski Mirosław, Grzesikiewicz Wiesław, Makowski Michał, Rutczyńska-Wdowiak Katarzyna

Journal of Automation, Electronics and Electrical Engineering

2022

Vol. 4, No. 2

17--21

In the paper we consider the issue related to the phenomenon of wheel-to-rail adhesion. This issue concerns self-excited vibrations in the area of wheel-rail contact, caused by unstable friction. Such friction is characterized by decreasing values of the friction coefficient with increasing slipping velocity. The paper includes mathematical formulation of the problem and presents the method for solving it. In addition, a simulation of elementary vehicle driving was performed. During the simulation, self-excited vibrations arose during wheel slip caused by high driving torque. The paper presents graphs illustrating the tangential force and the slipping velocity during these vibrations.

Efficiency improvement of forest machinery exploitation

Grigorev Igor, Kunickaya Ol'ga, Prosuzhih Alexey, Kruchinin Igor, Shakirzyanov Dmitry, Shvetsova Viktoria, Markov Oleg, Egipko Sergey

Diagnostyka

2020

Vol. 21, No. 2

95--109

The purpose of this work was to develop a model of the interaction process between the wheeled forwarder and the soil of the cutting area, which allows evaluating the influence of soil conditions, the parameters of the wheeled forwarder, as well as load and number of cycles of its application, on the indicators of resistance and adhesion of the forwarder to the traction surface. Modeling results for 3- and 4-axle forest machines with different load levels showed that for different soil categories, types of bodies, and tire sizes. The results of the approximation analysis enabled the derive of calculation formulas for estimating the propulsive coefficient and rut depth after the first passage depending on the values of load-bearing capacity, body load coefficient, wheel width, and soil deformation module. The proposed model can be used at laying down the skidding roads and its optimization not only in economic terms but also with respect to the environment as intensive harvesting operations lead to extensive soil destructions. The practical application of the results is expressed in increased performance capacities of wood skidding operations and minimization of costs for restoring the productivity of forest area.

The influence of temperature on the damping value of shock absorbers determined by the Eusama method

Jurecki Rafał S.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

2019

nr 60 (132)

34--40

The article presents the legal requirements for shock absorbers in suspension, for a vehicle in which they are mounted to be allowed on Polish roads. A short description of the working methodology of the device used to determine the effectiveness of a shock absorber’s damping (sometimes referred to as relative wheel adhesion) is given on the basis of the Eusama method. The method of carrying out the tests on a sample of five passenger cars are described, along with the tests carried out at different temperatures for shock absorbers installed in a suspension system. The results of the diagnostic tests of the shock absorbers carried out on a diagnostic stand, in accordance with the Eusama method, are presented. The results confirm that the ambient conditions – the temperature of the chassis components (including the shock absorbers) – only slightly influence the values of their damping efficiency.