جستجوی مقالات مرتبط با کلیدواژه « Rolling resistance » در نشریات گروه « مهندسی شیمی، نفت و پلیمر »

Rolling resistance sits at the core of tyre development goals because of its considerable ect on the car’s fuel economy. Rolling resistance depends many factors in a tire. The tread of tire have the most contributions in energy loss due to deformations caused by bending, pressure and shearing. Due to the long time of problem solving and the heterogeneity of numerical solutions as well as the inadequate understanding of the effect of different parameters on the rolling resistance, analytical solutions are used. . In this paper, by using the analytical method, the effect of various factors such as internal pressure, Young's modulus, tire load, belt radius, tread width, tread thickness, contact surface rate (csr) and sinδ on rolling resistance are investigated. . Finally, by using the Isight Design Gateway optimizer software, the optimal value of the tire rolling resistance in a TBR tire is obtained.

In this research, the physical-mechanical and rheological properties of the composites obtained from SBR1502, SBR1712, SBR1763 and SBR72612 filled with 55 silica Particles were investigated and compared. Also, given that the rheological behavior of rubber compounds can reflect many of the tire's functional properties, and knowledge of the rheological properties of the rubber materials enables us to predict the rolling resistance properly. In this study, the rheological properties of the samples were measured by RPA 3000. For this purpose, four samples were prepared with E1SBR / Silica, E2SBR / Silica, E3SBR / Silica and SSBR / Silica codes. The results of molecular weight distribution analysis showed that SSBR has the thinnest molecular weight distribution and the highest molecular weight. Also, examination of the mechanical properties showed that the E1SBR / Silica sample had the highest amount of elongation and the lowest Young's modulus, which increased the modulus of Young's modulus and molecular weight, respectively, and decreased the elongation percentage. Also, rheological properties analysis showed that SSBR / Silica sample had the lowest dissipation factor which is expected to have the lowest rolling resistance of the tire made with this sample. By examining the amount of rheological properties of the strain broom in the specimens, it can be found that the greater the storage modulus, the greater the amount of force at a constant percentage of elongation, which is fully consistent with the mechanical properties results.

Energy makes the wheels go round, thus driving the vehicle forward. As the wheel goes round, the tyre is deformed to make contact with the road. All the forces required for acceleration, braking and cornering are transmitted through this contact patch. As it is deformed, the tyre also absorbs road surface asperities. It is the tyre’s ability to be deformed which ensures grip and comfort. Keywords: Rolling resistance.

A 185/65R15 steel belted radial tire was analyzed for the prediction of its rolling resistance using finite element method. The Abaqus code was used for this purpose. A two-dimensional axisymmetric model was first designed to form the tire layout in the mold. After analyzing for rim mounting، an internal pressure was applied to the tire. Having rotated the tire cross-section about rolling axis، a three-dimensional model was then created and used for the analyses under static vertical load and steady state rolling conditions. Owing to the use of arbitrary Lagrangian/Eulerian framework، a constant linear velocity was assumed and the analysis was performed for a range of angular velocity of the tire. An in-house developed user subroutine was employed and linked to the Abaqus for the accurate determination of the free rolling rotational speed (angular velocity) of the tire based on zero force/torque. Two sets of analyses were performed. In the first set، it was assumed that the mechanical behaviors of the rubbery parts could be described by the well-known Ogden hyperelastic model. In the second set، hyper-viscoelastic behaviors were assumed in which the Ogden model was combined with the Prony series to take the material history and time effect into consideration. The difference between the calculated longitudinal forces in rolling state using the mentioned models was attributed to the rolling resistance of the tire. In order to check the accuracy of the proposed method، the predicted rolling resistance force was compared with that of experimentally obtained data which confirmed the applicability and robustness of the model. The contact pressure distributions have been presented and discussed in relation to different types of material model.

A high performance passenger tire tread compound was optimized for its mechanical، dynamical and thermal properties. A reference compound was based on a blend of SBR and BR، sulfur and other ingredients without accelerator، carbon black and aromatic oil. The effects of CBS/TMTD and TBBS/TMTD as accelerator systems were studied with different quantities and the best accelerator system was chosen. Then، the blends of N330 and N550 carbon blacks were added in different quantities and the properties of these samples were studied to determine the best carbon black blend. Finally، the effect of different quantities of aromatic oil was investigated and the optimized quantity of aromatic oil and the final properties of tire tread compound were defined. The mechanical and dynamical tests were carried out on appropriate samples to determine tensile strength، elongation-at-break، fatigue-to-failure، abrasion resistance، hardness، resilience، dynamical-mechanical properties and temperature rise due to the heat build-up. The results showed that the compound containing 0. 8 phr CBS، 0. 7 phr TMTD، 40 phr N330،20 phr N550 and 15 phr aromatic oils demonstrated the best properties.

Tire rolling resistance plays an important role in fuel consumption of automobiles. The main source of tire rolling resistance is viscoelastic loss of rubber compounds. Tire tread compound is the main source of viscoelastic loss among others. The change in rolling resistance of a tire with a new tread compound can be measured after manufacturing of new tire, which is time and money consuming. To reduce cost and time, prediction of energy dissipation of tire tread vulcanizates in rolling conditions has been considered. There are many methods for calculation of tire rolling resistance and/or measurement of energy dissipation in the tread compound under rolling condition in the laboratory. This article explains different methods for prediction of tire rolling resistance and illustrates the strengths and weaknesses of those methods.