Tire Rolling Resistance Research Articles

AERODYNAMIC AND ROLLING RESISTANCES OF HEAVY DUTY VEHICLE. SIMULATION OF ENERGY CONSUMPTION

The main objective of the work was to develop a comprehensive model of energy consumption simulation of heavy duty vehicles using the VECTO simulation tool. The research issue was the impact of aerodynamic drag and rolling resistance on fuel consumption and emissions under various driving conditions described in four driving cycles: Urban Delivery, Regional Delivery, Urban, and Suburban. Each cycle differed in driving time, distance and average speed to represent different operational scenarios. The methodology involved defining vehicle parameters such as weight, aerodynamic coefficients and tyre rolling resistance. The main findings show that the impact of both aerodynamic drag and rolling resistance on fuel consumption can be efficiently modelled. It has been proven that the proposed modifications to aerodynamic drag and rolling resistance can reduce fuel consumption by more than 8%. The lowest fuel consumption was achieved in the Regional Delivery cycle, while the Urban cycle had the highest fuel consumption due to frequent vehicle stops. The results show that optimization of vehicle design and its performance can significantly improve energy efficiency and reduce emissions. A computational modelling tool such as VECTO can contribute to sustainable transport solutions and improve the efficiency of heavy duty vehicle.

Application of wet carbon black masterbatch in green mining radial tires

AbstractIn the context of environmental protection and energy consumption reduction, reducing the rolling resistance of mining machinery tires is one of the important methods to achieve the goal of green mining. This study probes the effects of wet mixing with a wet carbon black masterbatch on the rolling resistance and grounding performance of wide‐body vehicle tire treads by investigating the cross‐linking structure, rubber–filler (R–F) interaction force, and physicomechanical properties of the wet mixing rubber compounded with a wet carbon black masterbatch. The results indicate decreases in the maximum torque‐minimum torque difference, cross‐link density, and R–F interaction of the wet mixing rubber and increased filler–filler (F–F) interaction and carbon black dispersion. Meanwhile, the tensile elongation of the wet mixing rubber increases, its DIN abrasion property improves, and its Tanδ decreases at 60°C. A numerical method to estimate tire steady‐state rolling resistance is also developed. Finite element simulation analysis reveals that the steady‐state rolling resistance of the wet mixing rubber is reduced by 7.04% at 100% standard load, and its grounding performance is enhanced. By proposing a method to reduce the rolling resistance of tires, this study also provides a reference for the development of wide‐body vehicle tires.Highlights Explored the filler interaction of wet mixing rubber. Explained the low energy loss of wet mixing rubber. Proposed a new finite element method for calculating tire rolling resistance.

GRAPHENE AS AN ANTIOXIDANT AND ANTIOZONANT IN TIRE SIDEWALL COMPOUNDS

ABSTRACT Tire sidewalls have an important function in achieving optimized tire performance. The sidewall compound must show good abrasion resistance, aging resistance, and tear strength; low hysteresis and minimal contribution to whole tire rolling resistance; and good adhesion to adjacent components in the tire. In addition, in both the original equipment market and the premium performance market, appearance is of considerable importance. The current system of waxes, antioxidants, and phenyl diamine antiozonants is very effective in meeting the need of the tire end user. However, recent concerns centered on the environmental impact of N′-phenyl-p-phenylenediamine, specifically N-(1,3-dimetylbutyl)-N′-phenyl-p-phenylenediamine, and staining and discoloration of the tire sidewall surface raise issues that should be addressed. Specialized grades of graphene can offer a mechanism by which tire appearance and environmental concerns can be overcome. Pristine graphene can improve compound resistance of ozonolysis and oxidation by replacing the current antiozonants and antioxidants used in tire compounds; improve tire sidewall appearance; and improve tire sidewall resistance to scuffing, abrasion, and tearing.

Simulation of transient rolling resistance of bicycle tyres at various ambient temperatures

Simulation of transient rolling resistance of bicycle tyres at various ambient temperatures

Optimizing the Honeycomb Spoke Structure of a Non-Pneumatic Wheel to Reduce Rolling Resistance

Traditional pneumatic tyres are prone to puncture or blowout and other safety hazards. Non-pneumatic tyres use a high-strength, high-toughness support structure to replace the “airbag body” structure of pneumatic tyres, which is made of fibre skeleton materials and rubber laminated layers, thus effectively avoiding the problems of blowout and air leakage. However, discontinuous spokes undergo repeated bending deformation when carrying loads, which leads to energy loss, of which the rolling resistance of non-pneumatic tyres is one of the main sources of energy loss. This paper focuses on the study of gradient honeycomb non-pneumatic tyres. Firstly, a finite element model was established, and the accuracy of the model was verified by numerical simulation and stiffness tests. Secondly, the order of the effect of different spoke thicknesses on rolling resistance was obtained through orthogonal test analysis of four-layer honeycomb spoke thicknesses. Then, four optimized design variables were selected in combination with the spoke angles, and the effects of the design variables on rolling resistance were analyzed in detail by means of the Latin hypercube experimental design. Finally, the response surface model was established, and the non-linear optimization model was solved by the EVOL optimization algorithm considering the tyre stiffness limitations so that the rolling resistance was minimized. The results of the study laid down theoretical and methodological guidance for the design concept and technological innovation of low rolling resistance comfort non-pneumatic tyres.

Steady-state rolling resistance prediction model of non-pneumatic tyres considering tread temperature: theory and experiment

Non-pneumatic tires have potential advantages over pneumatic tires, including lower rolling resistance. First, a non-pneumatic mechanical elastic wheel (ME-Wheel) was designed. Based on its structural characteristics, a tread temperature prediction model under steady-state rolling conditions was established, and the accuracy of the established model was verified through temperature measurement experiments. Combined with the tread temperature prediction model, a steady-state rolling resistance prediction model of ME-Wheel was established, and the basic parameters (ground length CL , ground width CW , radial stiffness SR ) required for the model were identified through experiments. Finally, the experimental data were compared with the predicted values under different speed and load conditions. The results showed that the average simulation value of the rolling resistance coefficient of ME-Wheel was 0.01853, which was positively correlated with speed and load. The test results and predicted values showed a similar trend under the same operating conditions, with a maximum error of less than 3.5%. This proved that the novel non-pneumatic tyre steady-state rolling resistance prediction model based on tread temperature could accurately predict the steady-state rolling resistance of tyres. This research addresses a significant topic in tyre technology and has the potential to influence future designs and optimizations of non-pneumatic tyres.

Comparison of Tire Rolling Resistance Measuring Methods for Different Surfaces

The rolling resistance of car tires is one of the most important parameters characterizing tires today. This resistance has a very significant contribution to the energy consumption of wheeled vehicles. The climate crisis has forced tire and car manufacturers to place great emphasis on the environmental impact of their products. Paradoxically, the development of electric vehicles has led to an even greater importance of rolling resistance, because in electric vehicles, a large part of the influence of grade resistance and inertial resistance has been eliminated due to re-generative braking, which resulted in rolling resistance and air resistance remain as the most important factors. What is more, electric and hybrid vehicles are usually heavier, so the rolling resistance is increased accordingly. To optimize tires for rolling resistance, representative test methods must exist. Unfortunately, the current standards for measuring rolling resistance assume that tests are carried out in conditions that are far from real road conditions. This article compares the results of rolling resistance tests conducted in road conditions with the results of laboratory tests conducted on roadwheel facilities. The overview of results shows that the results of tests conducted in accordance with ISO and SAE standards on steel drums are very poorly correlated with more objective results of road tests. Significant differences occur both in the Coefficients of Rolling Resistance (CRR) and in the tire ranking. Only covering the drums with replicas of road surfaces leads to a significant improvement in the results obtained. For investigations of rolling resistance in non-steady-state conditions, the flat track testing machine (TTF), equipped with asphalt cassettes, is shown to provide measurement data in agreement with the road test data.

Comparison of e-scooter tyre performance using rolling resistance trailer

AbstractE-scooters are a cost-effective means of urban transport, however, there have been questions about their safety, performance, and energy efficiency. This paper investigates the rolling resistance of scooter tyres so that the performance of scooters can be more accurately determined. A rolling resistance trailer was manufactured to directly measure tractive force and closely approximate the rolling resistance force for nine commonly used scooter tyres at low speed on a smooth concrete surface. The results of this study will enable a better understanding of the energy losses of these devices.

Environmental Impact Prediction of a New Tire Vulcanization Activator.

Zinc oxide (ZnO) is the most common curing activator used to manufacture tires. To minimize environmental impacts by decreasing the zinc content and rolling resistance of tires, ZnO nanoparticles (NPs) anchored on SiO2 NPs (ZnO@SiO2) are currently under development as new activators at the pilot scale. Here, we applied prospective life cycle assessment to predict the impacts on human health, ecosystem quality, and resource scarcity of synthesizing ZnO@SiO2 for the production of passenger car tires at an industrial scale. We found that the life cycle impacts of the synthesis are expected to decrease by 89 to 96% between the pilot and industrial scale. The largest contributors to the synthesis of ZnO@SiO2 were electricity consumption and waste treatment of the solvent. Using the new activator for tire production led to potential reductions of 9 to 12% in life cycle impacts compared to tires that are currently in use. Those reductions were due to the expected decrease in rolling resistance, leading to lower fuel consumption, which outweighed the additional environmental impacts of the synthesis, as well as the potential decrease in lifetime. Our work highlights an opportunity for manufacturers to mitigate their impacts over the full life cycle of the tire.

Analysis of tire-pavement interaction modeling and rolling energy consumption based on finite element simulation

Energy consumption is caused by the rolling resistance of tires as a vehicle moves forward, which contributes to resource consumption and the greenhouse effect. The objective of this paper is to investigate the variation of tire-pavement rolling energy consumption under different operating condition factors. For this purpose, a rolling finite element dynamic model was developed based on real tire and road contact. The correlation between the effective radius and free angle is determined during the free rolling process. The variations of different working conditions on rolling energy consumption under tire-road coupling were analyzed according to both tire and pavement factors, and the influence factors were analyzed by grey correlation analysis. The results show that the factors affecting the significance of rolling energy consumption in descending order are tire load, tire pressure, coefficient of friction, pavement stiffness, and rolling speed. Specifically, energy consumption can be increased by increasing the tire load or friction coefficient, the cumulative increase of rolling energy consumption reaches 68.3% and 14.51%, respectively. Energy consumption can be decreased by increasing the tire pressure or pavement stiffness, the cumulative decrease in energy consumption is 20.45% and 5%, respectively. In addition, the rolling energy consumption increases and then decreases within an increasing speed range(10–80 km/h). The speed trend inflection point is 20 km/h. The research results can provide a technical reference for the development of a low-energy consumption design scheme for tire-pavement systems. To better serve the construction needs of green low-carbon and sustainable road transportation.

Metamodeling on uncertainty quantification in the behavior of the tire/road interaction of vehicles

In recent years, the automotive industry has been developing applied research to meet customer’s needs; considering safety, vehicle comfort and energetic efficiency. In particular, automotive tires have a prominent position in this research area, ensuring good vehicle handling, comfort and safety. In the vehicle dynamics performance, excellent gripping and reduced rolling resistance in the tires are crucial to maximize the energetic efficiency in a reliable way. However, to ensure such a level of reliability in vehicle operation, the inherent uncertainties of tires, as well as other factors subject to variability must be taken into account in the vehicle design. In this way, the present paper analyzes in detail the effect of variations in some parameters such as ambient temperature, ground conditions, vertical load, speed and tire inflation on the analysis of vehicle dynamics. A Metamodeling approach associated with the Monte Carlo Simulation was employed to develop the mathematical models to analyze the effect of uncertain parameters on the tire rolling resistance; traction, centripetal and lateral forces, using experimental data from the literature, in the longitudinal and lateral vehicle dynamics. Therefore, the present research brings as an innovation an integrated approach to the input parameters of the system with the rolling resistance through the developed metamodels. There was a substantial variability of up to 15% both up and down in the Maximum Traction Force of a vehicle in response to variations in the vehicle’s weight and the coefficient of tire rolling resistance. In contrast, the Lateral Force exhibited a greater variability, with a 25 downward and 10% upward variation associated with the weight and friction coefficient variability of the vehicle. Further investigations into the sensitivity analysis highlight the significant influence of the friction coefficient and temperature on the Traction Forces of the vehicle.

Assessment of the increase in operating fuel consumption of a KAMAZ long-haul road train in winter conditions

The performance indicators of wheeled vehicles — fuel consumption and speed of cargo delivery — have always been and remain one of the key factors ensuring their high efficiency for the consumer. To increase efficiency, specialists of KAMAZ PJSC have developed and are producing new generation vehicles of the fifth environmental class with improved fuel efficiency. Practice shows that owners of new cars do not have basic fuel consumption standards and various surcharges for them. For this reason, they are forced to turn to the manufacturer, and the manufacturer, in accordance with current legislation, does not have the right to develop standards. Anticipating possible requests from owners of new cars, the authors tried to present in a systematic form the factors affecting fuel consumption and assess its possible increase in winter conditions for the KAMAZ long-haul road train. Keywords wheeled vehicle, road train, operational fuel consumption, operating conditions, tire rolling resistance, aerodynamic resistance

A semi-physical thermodynamic transient rolling resistance model with nonlinear viscoelasticity

Rolling resistance dictates a large part of the energy consumption of trucks. Therefore, it is necessary to have a sound understanding of the parameters affecting rolling resistance. This article proposes a semi-physical thermodynamic tyre rolling resistance model, which captures the essential properties of rolling resistance, such as transient changes due to temperature effects and the strain-amplitude dependency of the viscous properties. In addition, the model includes cooling effects from the surroundings. Both tyre temperature and rolling resistance are obtained simultaneously in the simulation model for each time step. The nonlinear viscoelasticity in rubber is modelled using the Bergström–Boyce model, where the viscous creep function is scaled with temperature changes. The cooling of the tyre is considered with both convective and radiative cooling. Moreover, the article explains different material parameters and their physical meaning. Additionally, examples of how the model could be used in parameter studies are presented.

A method for quantifying the resistances of light and heavy-duty vehicles under in-use conditions

Tyre rolling resistance and air drag significantly affect road-vehicle fuel and energy consumption. Their importance is recognised in vehicle certification regulations and standards worldwide. Detailed methodologies for their determination exist that require testing in dedicated proving grounds or specialised test facilities outside of actual driving conditions. As countries strive to improve vehicle efficiency, in-use verification of vehicle resistances will become essential for research and vehicle homologation. Multiple factors may limit such activities such as cost, lack of dedicated test infrastructure and equipment, and incompatibility with other vehicle-related tests that already take place. This study proposes a new method for determining vehicle resistances during on-road measurements based on wheel torque data. The method allows less expensive, more versatile test procedures that could be applied to a wide sample of vehicles across the fleet. The method was evaluated experimentally with nine vehicles (3 light-duty, 6 heavy-duty). Repeatability tests showed that the air drag error standard deviation ranged from 1 to 5.5 % for light-duties, and the pooled error standard deviation was 5.8 % among all heavy-duty vehicles. The results showed a divergence from the target cycle energy demand of <5 % during the on-road tests, a limit indicating the highest expected test discrepancy due to test uncertainties. Vehicle fuel consumption was simulated with both the measured and official resistance coefficients as a secondary validation. The on-road calculated coefficients led to accurate estimates of real-world consumption. The study discusses the impact of the wind vector during the test on the air drag and resistances’ influence on consumption.

Conceptual Design and Energy Efficiency Evaluation for a Novel Torque Vectoring Differential Applied to Front-Wheel-Drive Electric Vehicles

This paper presents a novel differential with lateral torque vectoring activated by an auxiliary motor, called motor-modulated lateral torque vectoring differential, or briefly, MLTD. Its architecture and kinematic characteristics are described, and the optimal cornering performance due to torque vectoring is evaluated using a steady-state vehicle dynamic model. Then, a conceptual design case of MLTD installed in a front-wheel-drive electric vehicle is conducted to assess its feasibility in terms of cornering, driving performances, and energy efficiency performance. The calculations show that an optimal distribution ratio between left and right torques for maximum lateral acceleration can be obtained for a specific cornering condition, further used for DM sizing in the preliminary stage. The simulations for energy consumption at constant-speed turning reveal that energy efficiencies of MLTD are lower than those of conventional differentials with evenly distributed torques. However, this deficiency may be paid off by moderately cutting down the rolling resistance of tire while the superior cornering performances brought by torque vectoring is still preserved. Accordingly, the newly proposed MLTD possesses greater flexibility to improve energy efficiency and driving range of electric vehicles without trading off against its desirable cornering performance and safe handling, and is thus worthy of further development.

Rubber Comprehensive Constitutive Equation and the Prediction of Tire Temperature and Rolling Resistance

ABSTRACT Cooler running tires with a reduced rolling resistance is a consideration for both tire makers and automotive original equipment manufacturers. To investigate the mechanics of energy loss and temperature rise, a nonlinear viscoelastic model suitable for numerical analysis of rolling tires is developed and demonstrated. The rubber compounds are represented as nonlinear viscoelastic materials with temperature and frequency, strain, and strain history–dependent response. Several applications to different tire designs are provided to demonstrate the impact of this new material constitutive law in improving the quality of the numerical predictions over other methods. One application is a rolling tire model that was used to delineate the tire temperature distribution and the resultant rolling resistance for different three-dimensional tread patterns.

Truck tyre transient rolling resistance and temperature at varying vehicle velocities - Measurements and simulations

Rolling resistance is causing a significant part of the energy consumption in truck applications, especially at low-speed levels. To be able to better estimate the energy consumption or remaining driving range, the truck tyre rolling resistance must be understood well. Temperature is a vital parameter for rolling resistance estimations. This article shows truck tyre rolling resistance and temperature measurements in a climate wind tunnel and simulations of tyre temperature and rolling resistance. During the climate wind tunnel tests, tyre temperature at the shoulder and tread was measured. In addition, on-road driving was conducted with inner-liner infrared temperature measurements. Tyre temperature simulations were conducted using a thermal tyre model with speed-variable thermal inertia. The comparison of tyre temperature simulations with measured inner-liner and shoulder temperatures showed good agreement with the test data. The rolling resistance was simulated using the principle of time-temperature superposition, and a master curve for rolling resistance and a curve for tyre temperature shift were constructed. These curves were used to simulate rolling resistance at a wide range of speed levels with good agreement to the experimental results. The investigation showed that the tyre shoulder temperature is a better indicator of rolling resistance than infrared measurements from the tyre tread.

Effects of β‐dextranase in raw natural rubber on the interface and performance of natural rubber/silica composites via simulation with an outer same protein

AbstractAs one of the non‐isoprene components in raw natural rubber (NR), proteins always act an important role to the final performance of the filled rubber composites. In this work, we involved a natural protein β‐dextranase externally to simulate the same protease in raw NR, and analyzed the effects of β‐dextranase content on the dispersion of silica particles, mechanical performance, viscoelastic loss of NR/silica composites. β‐dextranase acts with silica through an intense hydrogen bond interaction, which improves silica dispersion and strengthens the mechanical properties of NR/silica composites obviously when loading 4 wt% β‐dextranase, as well as the ameliorative UV aging resistance. As a consequence, the energy loss of the composites is decreased remarkably, showing great advantage in low rolling resistance tire. Besides, the results could offer the data reference to the breeding, deep processing and application of NR.

Study on the influence of cornering characteristics of complex tread tires on rolling resistance based on finite element method

The existence of tire slip angle and camber angle causes that the test results of conventional rolling resistance tester are often very different from the measured results installed on the vehicle. In addition, the test cost of rolling resistance tester with sideslip and roll is high. To solve the above problems, the effects of cornering characteristics on rolling resistance of complex tread tires were analyzed by finite element method (FEM). The numerical simulation model of a tire with complex tread patterns was established, and the reliability of the established numerical simulation model was verified by the experiments. The response relationships between tire lateral force, sideslip angle, camber angle and rolling resistance under multiple pure sideslip conditions and combined conditions were compared and analyzed, as well as the contribution rate of each tire component to rolling resistance under the corresponding conditions. The obtained research results can provide support for vehicle chassis adjustment and energy saving and consumption reduction in tire structure design.

Climate-mine life cycle interactions for northern Canadian regions

This study quantifies the impacts of climate change on the mine life cycle (development, operation and closure phases) of 30 mines located in the northern regions of Canada. To this end, climate projections based on a five-member transient climate change simulation ensemble, performed using a state-of-the art regional climate model, spanning the 1991–2050 period, corresponding to the Representative Concentration Pathway 8.5 emission scenario are used. A reanalysis-driven simulation for the 1991–2010 period compared against available observations confirm suitability of the model for application in climate change simulations. Assessment of projected changes to mine-relevant climate variables that are important from structural integrity and operation perspectives reveal potential vulnerabilities and opportunities. Active layer thickness increases in the 0.3–2 m range in permafrost regions, coupled with increases in flood probability, as reflected in snow-melt rate increases in the 0.14–6.77% range and increases in the 100-year return levels of daily maximum rainfall in the 5–50% range, suggest potential impacts on the structural integrity of mine infrastructure, such as slope instability and foundation settlement of tailings dams, and supporting infrastructure such as ice/all-season roads. Increases in soil moisture, projected in the 0–11% range, at a few mines, suggest potential impacts on material handling systems, such as increases in the traction factor of the muck-haul and tire rolling resistance, that can lead to low productivity. Projected increases to wind speeds in the 5–10% range for the northernmost regions suggest potential impacts on the tailings management facility in terms of increases in tailings resuspension. Overall, this study identified northernmost and northeastern mines to be more vulnerable, with air/soil temperature, precipitation and wind speed being the most influential climate variables. This systematic study, for the first time, has identified potential vulnerabilities of northern Canadian mines, which can inform future high-resolution climate modelling and detailed at-site climate-mine interaction studies that is required for climate-change adaptation related decision-making.