Showing 6 results for Tire
H. Golbakhshi, M. Namjoo, M. Mohammadi,
Volume 4, Issue 1 (3-2014)
Abstract
The dissipated energy from periodic deformation is regarded as the main reason for heat generation and temperature rise inside the tire domain. However, the mechanical behavior of rubber parts is highly temperature dependent. In most performed investigations, the influence of thermal effects on stress/ deformation fields of pneumatic tires is ignored and just temperature distribution is considered. Hence in this study, using a series of 2D and 3D finite element models, a robust and efficient numerical study is presented for thermo-mechanical analysis of pneumatic tires specially 115/60R13 radial tire. Finally, the effects of loading condition s and ambient temperature on the thermo-mechanical properties of tire are investigated in detail. Comparing the obtained results with the available results in literature, shows a good agreement of the presented studies with related published works.
M. Namjoo, H. Golbakhshi,
Volume 4, Issue 3 (9-2014)
Abstract
The natural frequencies and mode shapes of pneumatic tires are predicted using a geometrically accurate,
three-dimensional finite element modeling. Tire rubber materials and cord layers are represented
independently using “shell element” available in COSMOS. The effects of some physical parameters such
as the inflation pressure tread pattern, thickness of belts and ply angles to the natural frequencies of tires are
investigated. By imposing equivalent centrifugal forces, the effect of translational speed on vibrating
behavior of the tire is also studied in this work. Comparisons of numerical and experimental results are
given to show the validity of the proposed model.
B. Mashhadi, H. Mousavi, M. Montazeri,
Volume 5, Issue 1 (3-2015)
Abstract
This paper introduces a technique that relates the coefficients of the Magic Formula tire model to the physical properties of the tire. For this purpose, the tire model is developed by ABAQUS commercial software. The output of this model for the lateral tire force is validated by available tire information and then used to identify the tire force properties. The Magic Formula coefficients are obtained from the validated model by using nonlinear least square curve fitting and Genetic Algorithm techniques. The loading and physical properties of the tire such as the internal pressure, vertical load and tire rim diameter are changed and tire lateral forces for each case are obtained. These values are then used to fit to the magic formula tire model and the coefficients for each case are derived. Results show the existing relationships between the Magic Formula coefficients and the loading and the physical properties of the tire. In order to investigate the effectiveness of the method, different parameter values are selected and the lateral force for each case are obtained by using the estimated coefficients as well as with the simulation and the results of the two methods are shown to be very close. This proves the effectiveness and the accuracy of the proposed method.
M. Namjoo, H. Golbakhshi, H. Momeni-Khabisi, F. Khoshnam,
Volume 6, Issue 3 (9-2016)
Abstract
Evaluating the thermal effects and variations in temperature of rolling pneumatic tires, is a very important factor in safe performance of the vehicles. Normally, the transient thermal investigation of rolling tires is performed by tire test rigs. However, experimental analysis is a very time and cost consuming process and because of technical limitations, the tests cannot be carried out in most severe conditions. In this work, a validated finite element model is proposed for transient thermal investigation of rolling pneumatic tires. Compared with the experimental tests, the current study gives satisfactory results for temperature distribution of the tire.
B. Mashhadi, M.a. Vesal, H. Amani,
Volume 7, Issue 3 (9-2017)
Abstract
This paper presents a force field concept for guiding a vehicle at a high speed maneuver. This method is
similar to potential field method. In this paper, motion constrains like vehicles velocity, distance to obstacle
and tire conditions and such lane change conditions as zero slop condition and zero lateral acceleration are
discussed. After that, possible equations as vehicles path are investigated. Comparing advantages and
disadvantages of 7th, 11th degree and a few other equations, followed by single mass and bicycle models
lead to an improved method, which is presented in this paper.
Mahdi Ajami, Hossein Jannat, Masoud Masih-Tehrani,
Volume 10, Issue 4 (12-2020)
Abstract
Braking test is one of the most important tests of a mechanized technical inspection line. In this study, the effect of tire pressure changes on the accuracy of the braking test results is investigated at technical inspection centers. This study is conducted in three stages. In the first step, the braking efficiency at different tire pressures is examined using a roller brake tester. In the second step, the tests at different pressures and velocities on the road are done. These tests are carried out in terms of stopping distance, to ensure the accuracy and reliability of the first step test results. The results of the first and second steps showed that the effect of tire pressure changes on the braking efficiency is significant. In the third step, the braking test results of a thousand vehicles that received technical inspection certificate are studied. Analysis of these results, considering the results of the first and second steps cleared that about 16% of vehicles that received technical inspection certificate have lower braking efficiency than the minimum acceptable efficiency. The obtained results specified the necessity of adjusting the pressure of tires before the braking test at vehicle technical inspection centers in Iran.
