bluuebunny/crossref_metadata_2025_split huggingface dataset:
End Effects in Twisted Cord-Rubber Composites
Authors: Padovan J. 
Published: June 2006

Abstract
This paper investigates the cord-matrix load transfer problem in twisted cord-rubber composites. The central feature of the study is to ascertain the polarizing effects of twist-induced coupling of the axial loads and torque. Particular emphasis is given to the end problem, namely the transition between the axial-circumferential shear stress-dominated end region and the axial normal stress and torque-controlled far-from-end zone. This is achieved through the development of both a closed form analytic formulation and its corroboration by a detailed finite element simulation.
Torsional Analysis of a Steel Cord-Rubber Tire Belt Structure
Authors: Pidaparti R. M. V. 
Published: June 2006

Abstract
A three-dimensional (3D) beam finite element model was developed to investigate the torsional stiffness of a twisted steel-reinforced cord-rubber belt structure. The present 3D beam element takes into account the coupled extension, bending, and twisting deformations characteristic of the complex behavior of cord-rubber composite structures. The extension-twisting coupling due to the twisted nature of the cords was also considered in the finite element model. The results of torsional stiffness obtained from the finite element analysis for twisted cords and the two-ply steel cord-rubber belt structure are compared to the experimental data and other alternate solutions available in the literature. The effects of cord orientation, anisotropy, and rubber core surrounding the twisted cords on the torsional stiffness properties are presented and discussed.
Finite Elements Developed in Cylindrical Coordinates for Three-Dimensional Tire Analysis
Authors: Danielson K. T. , Noor A. K. 
Published: June 2006

Abstract
Finite elements developed in cylindrical coordinates are presented for three-dimensional analysis of tires. In contrast to elements formulated in Cartesian coordinates, these elements allow the exact representation of circular shapes. The exact modeling of circular geometries can provide better finite element predictions and reduce the number of elements needed around the tire circumference. Numerical results are presented for the application of this formulation to the analysis of a radial automobile tire subjected to rim mounting, nonconservative inflation pressure, and rigid pavement contact. The predictions of the foregoing finite elements are compared to experimental data and to predictions of a commercial code using finite elements developed in Cartesian coordinates. The comparisons demonstrate the accuracy and the advantages of the cylindrical coordinate formulation for the three-dimensional finite element analysis of tires.
Experimental Results and Analysis of Aircraft Tire-Test Drum Interaction
Authors: Lindsley N. , Medzorian J. , Padovan J. 
Published: June 2006

Abstract
Although aircraft tires are traditionally tested on external drum dynamometers, the effects of the curvature of the test surface on the normal contact pressure distribution and footprint area of an aircraft tire have not previously been addressed. Using the tire force machine (TFM) at the Wright Laboratory Landing Gear Development Facility (LGDF), trends in tire footprint area and normal contact pressure distributions were investigated for concave, flat, and convex surfaces. This evaluation was performed using the F-16 radial (25.5×8.0 14PR) main landing gear tire at rated load (16,200 lbf) and inflation pressure (310 psi). The trends for overall tire footprint behavior indicate that the more convex the surface, the smaller the contact area and the larger the normal contact pressure. Conversely, the more concave the surface, the larger the contact area and the smaller the normal contact pressures. All data were made symmetric about the longitudinal and lateral centerlines. This process and its effect on the data are discussed at length in the analysis sections. Additionally, it was found that after normalizing the normal contact pressure data with respect to contact length and maximum pressure for the individual tire ribs, the normal contact pressure longitudinal distributions were “identical” (within ±5%) regardless of surface curvature. Comparisons are made with numerical experiments on a treadless, homogeneous polyurethane automobile tire.
Heavy Truck Handling Performance Analysis in Vehicle Test and Computer Simulation
Authors: Schröder C. , Duchow A. 
Published: June 2006

Abstract
The dynamic stability of heavy trucks, as spinout, jackknifing, and rollover, is highly dependent on vehicle configuration, driving maneuver, and the force and moment characteristics of tires. Increasing safety requirements on the handling performance of heavy trucks demand tools that allow a tire design engineer to predict tire influences on the tire/vehicle system dynamic behavior. The computer simulation of handling performance of vehicles offers possibilities of evaluating influences of tire design changes on handling properties in any developing stage of new tire lines. Thus, modern simulation techniques may contribute to the building and testing of tires in an early design stage. This paper presents results from a recent program of tire/vehicle system research, applying tire/vehicle testing and simulation techniques to a 40 ton truck-semitrailer combination. The goal of this work is to visualize the possibilities of state-of-the-art simulation technologies on the tire design process. Tire force and moment characteristics can be calculated from the tire layout by an advanced tire model. The tire model for this type of calculation is a multibody system. Calculated and measured dynamic tire characteristics are used for the full vehicle handling simulation in ADAMS. Extensive tire characteristic testing on the road and test stand was done to improve and validate the tire model. Vehicle handling tests as steady state circular and lateral transient response tests were done for the empty and laden vehicle with different tires to prove the vehicle model. With the use of the simulation of the tire and vehicle behavior, the tire design engineer will be able to judge tire characteristics of different variants in an early design stage. Vehicle dynamic simulation studies up to instability as spinout, jackknifing, and rollover can be performed using modern CAE methods without harming man and environment, but subjective and objective tire evaluation still remains necessary for approving and validating the predicted results.
Effect of the Environment on the Wear of Carbon Black-Filled Natural Rubbers?
Authors: Uchiyama Y. , Han Y. , Iwai T. 
Published: June 2006

Abstract
In this study, the effect of the environment on the wear of natural rubber (NR) vulcanizates containing three kinds of carbon black, namely, HAF(N330), ISAF(N220), and SAF(N110), were examined. The friction coefficient and wear rate of each carbon black-filled NR tended to decrease with decreasing ambient air pressure. In air, the wear rates of NR vulcanizates containing ISAF and SAF were lower than NR containing HAF. No difference in the former two vulcanizates could be observed. However, at a reduced air pressure of 66 Pa, the wear rates of NR with ISAF and SAF were 22% and 7%, respectively, when compared with that of NR with HAF. With a reduction in the size of carbon black, a large difference in the wear rates could be seen in vacuum.
3D Simulations of Automobile Tires: Material Modeling, Mesh Generation, and Solution Strategies
Authors: Meschke G. , Payer H. J. , Mang H. A. 
Published: June 2006

Abstract
The paper addresses finite element formulations for automobile tires considering nonlinear material behavior, large strains, and finite deformations while using efficient computational strategies for realistic large-scale 3D finite element simulations. A new 3D finite element model for cord-reinforced rubber composites is employed for the numerical representation of the reinforcing plies. A hyperelastic Mooney material law in conjunction with a hybrid finite element formulation is used for the modeling of the rubber material. A strategy for the generation of locally refined finite element meshes of automobile tires is developed. Several computational strategies, together with an iterative solver, are proposed to improve the computational efficiency. 3D simulations of factional static contact of automobile tires on a rigid road surface, involving the determination of the pressure distribution in the contact zone, are presented.
Analysis of Temperature Distribution in a Rolling Tire Due to Strain Energy Dissipation
Authors: Park H. C. , Youn S-K. , Song T. S. , Kim N-J. 
Published: June 2006

Abstract
This paper addresses a systematic procedure using a sequential approach for the analysis of the coupled thermomechanical behavior of a steady state rolling tire. Not only knowledge of mechanical stresses but also knowledge of the temperature loading in a rolling tire are very important because material damage and material properties are affected significantly by the temperature. In general, the thermomechanical behavior of a pneumatic tire is a highly complex transient phenomenon that requires the solution of a dynamic nonlinear coupled thermoviscoelasticity problem with heat sources resulting from internal dissipation and friction. In this paper, a sequential approach, with effective calculation schemes, to modeling this system is presented to predict the temperature distribution with reasonable accuracy in a steady state rolling tire. This approach has three major analysis modules: deformation, dissipation, and thermal modules. In the dissipation module, an analytic method for the calculation of the heat source in a rolling tire is established using viscoelastic theory. For the verification of the calculated temperature profiles and rolling resistance at different velocities, they are compared with measured ones. Also, discussed are the accuracies of the linear and quadratic finite element models used in the analysis.
Airbag Tire Modeling by the Explicit Finite Element Method
Authors: Wu S. R. , Gu L. , Chen H. 
Published: June 2006

Abstract
An explicit finite element code FCRASH has been applied to both static and dynamic tire modeling. The computational procedure for predicting tire loads has been investigated. The typical tire model used in the simulation consists of a tire and rim. The tire is defined by membrane elements and the rim by rigid body with shell elements. The tire and rim form a closed volume. The airbag functionality in FCRASH, an explicit finite element code developed by Ford Motor Company, has been employed to simulate the test and to monitor the pressure and volume changes in the tire. Three static tire models (Taurus spare tire, P145/75R12, and P225/60R16) have been studied and the force-deflection curves are compared with test data. All of them exhibit a very good agreement. The standard spindle test for the P145/75R12 tire at three different speeds (10, 20, and 30 mph) is also simulated. The prediction of vertical and horizontal forces at 30 mph shows an excellent agreement with the test. The results for 20 and 10 mph are also reasonably good. The simulations for complex road conditions and full vehicle over bumps with a concept model are also performed as a feasibility trial. The CPU time used in both HP735 and CRAY computers for all these cases are comparable with other major CAE jobs. The experiments show that the explicit finite element code has a lot of advantages and strong potential to perform durability road load analysis with affordable computer costs.
A Study on the Analysis of Surface Stresses of Pneumatic Tires by the Photoelastic Method
Authors: Kim N. J. , Park B. K. , Ahn J. R. 
Published: June 2006

Abstract
The pneumatic tire has a very complicated geometrical shape and is subjected to large deformations. Measurement of the stress and strain distributions in the tire is difficult. In this study, the reflective photoelastic method was used to measure the distributions of stress and strain on the surface of the tire sidewall. It was assumed that the pneumatic tire takes the shape of a toroidal shell of revolution and that the strain of the photoelastic coating is the same as that of the tire surface. The force equilibrium equations for shell elements were derived and the principal stresses were extracted by the shear difference method. The normal stresses and the shear stresses were obtained by numerically integrating the equilibrium equations. The initial values for the integration were determined using the oblique incidence method.
Fatigue Crack Propagation in Metals and Polymers with a Unified Formulation
Authors: Chow C. L. , Lu T. J. 
Published: June 2006

Abstract
As the traditional ΔK-based fatigue crack propagation (FCP) law has recently been elucidated by Chow and his group [1–7] to be inadequate for a complete description of fatigue cracking, we examine in this investigation the applicability of a unified formulation for characterizing FCP of both metals and nonmetals. We start by defining a new cyclic J-integral, ΔJ, which, under the confines of linear elastic fracture mechanics (LEFM), is equivalent to the range of elastic strain energy release rate, ΔG. ΔJ (or ΔG) is used as a proper criterion for FCP so long as the crack does not extend during the unloading portion of one load reversal. ΔJ (or ΔG) as such is also interpreted as the source supplier for the energy flow rate dissipated on crack-tip cyclic plastic deformations. It is then assumed that, under fixed test conditions, the minimum specific work of fracture required for fatigue crack initiation, ΔJth, is a material property independent of the load ratio R. Fatigue threshold values thus predicted are correlated favorably with experimental measurements. For fatigue crack propagation, a unified formulation is subsequently derived from the thermodynamic theory of irreversible processes with the cracked surface area taken as an internal variable together with the assumption that the rate of energy dissipated on FCP depends on ΔJ only. It is noted that, in addition to ΔJ, the role played by (Jc − Jmax) is also required in the unified FCP law. Applicability of the law for producing a master FCP diagram is finally examined using FCP data of both metals and polymers, including mild steel, aluminium alloys, PMMA, PVC, short fiber composites, and adhesives.
Interply Shear Stresses and Coupled Deformations of a Folded Belt Structure Under Extension
Authors: Akasaka T. , Kato M. , Wakatsuki H. 
Published: June 2006

Abstract
The folded belt construction has been developed to reduce the shear stress concentrations at the belt edge and to stabilize the bending interaction with the carcass at the shoulder. An analysis is given to obtain the characteristic distributions of interply shear stresses and coupled extensional-torsional and extensional-bending deformations of the folded belt comprised of a one-layer Cord Reinforced Rubber (CRR) sheet under axial tension. It was shown that the interply shear stress concentrations surely disappeared at the folded belt edge but appeared alternatively at the free end of the rolled-up belt sheet and the tensile stress in the axial direction concentrated heavily in the laminated belt part. The experimental verification of the predicted distribution of the interply shear stresses was conducted by measuring the in-plane shear membrane force of a belt sheet.
Model Reference Adaptive Control of a Tire Test Machine
Authors: Kline S. M. 
Published: June 2006

Abstract
A typical tire endurance testing machine (TTM) is described and a new digitally controlled TTM is proposed. Currently TTMs normally use an analog PID-type servo loop to control the force with which a tire is pressed against a large turning road-wheel (radial load control). The camber angle and steer angle of the tire are both normally constant and zero. This type of system does not perform well with changing radial loads because the system dynamics are influenced by the tire's weight and spring constant which varies from tire to tire. Analog electronic control cannot adapt to these parametric changes but digital control can. In this paper a model reference adaptive controller is proposed. This type of control allows specific loading dynamics (the reference model) to be programmed independently of tire weight and spring constant. This enables the user to emulate a specific suspension system on a bumpy road simply by specifying the suspension dynamics and the changes in load.
Deformation Analysis of a Radial Tire Loaded on a Crossbar
Authors: Akasaka T. , Kagami S. , Yamazaki S. 
Published: June 2006

Abstract
The spring characteristics of a radial tire loaded on a crossbar put on a roadway was analyzed with a spring bedded ring model. Nonlinear radial and tangential spring effects of the sidewall and large deformation of the tread were considered. The tread curvature in the cross section was found to be the most important structural factor for elucidating the enveloping properties of a radial tire in contact with a crossbar. Experimental verifications of the spring effect and the tread deformation of a radial tire were in good agreement with the theoretical predictions.
Spinup Wear in Aircraft Tires
Authors: Padovan J. , Padovan P. , Kazempour A. 
Published: June 2006

Abstract
This paper develops a cost-effective analytical-numerical simulation procedure which models the tire wear problem resulting from the spinup process associated with high-speed aircraft landings. The resulting model can represent the energy transfer at the tire-runway interface, the rotary momentum absorption process, the steep thermal gradients in the interface region as well as the high wear rates resulting from the combined thermal degradation of the rubber (reversion, melting, ablation) and mechanical machining by runway asperities. This is illustrated in a series of parametric numerical studies defining the parametric effects of a variety of system factors.
Force Transmissibility of Heavy Truck Tires
Authors: Tielking J. T. 
Published: June 2006

Abstract
A laboratory study of force transmission in radial truck tires is described. The experiments are conducted with the tire-wheel assembly attached to a fixed, nonrotating axle. Contact with the tire is provided by a flat surface. Single frequency displacement cycles are applied to the loaded tire footprint, and the dynamic force transmitted through the tire is measured at the fixed axle. Fourier transform signal analysis is used to extract the cyclic displacement and force amplitudes. The amplitude ratio force/displacement is defined as the force transmissibility. The experiments show inflation pressure and tire load to have little effect on force transmissibility. A single degree of freedom tire model for force transmissibility is described. The model uses easily measured tire parameters and is intended for use in vehicle models to include the effect of tire dynamics.
Influence of Rim Run-Out on the Nonuniformity of Tire-Wheel Assemblies
Authors: Rhyne T. B. , Gall R. , Chang L. Y. 
Published: June 2006

Abstract
An analytical membrane model is used to study how wheel imperfections are converted into radial force variation of the tire-wheel assembly. This model indicates that the radial run-out of the rim generates run-out of the tire-wheel assembly at slightly less than the one to one ratio that was expected. Lateral run-out of the rim is found to generate radial run-out of the tire-wheel assembly at a ratio that is dependent on the tire design and the wheel width. Finite element studies of a production tire validate and quantify the results of the membrane model. Experiments using a specially constructed precision wheel demonstrate the behavior predicted by the models. Finally, a population of production tires and wheels show that the lateral run-out of the rims contribute a significant portion to the assembly radial force variation. These findings might be used to improve match-mounting results by taking lateral rim run-out into account.
Tire Rolling Loss Computation with the Finite Element Method
Authors: Luchini J. R. , Peters J. M. , Arthur R. H. 
Published: June 2006

Abstract
This paper describes a process for the prediction of rolling resistance in tires. A new Directional Incremental Hysteresis (DIH) theory describing the hysteretic behavior of carbon black filled rubber is presented. The steps required to implement the DIH theory in a material model, within a Finite Element (FE) model, and to predict tire rolling resistance are described.
The material model using the DIH theory is a strain-based model which includes an incremental formulation to deal with nonsinusoidal cycles within tires. The material model is also enhanced by a directional formulation which is active in situations where the strain tensor has a substantial change in direction with minimal change in magnitude. The hysteresis material model is developed only for the rubber compounds of the tire. While there is no direct contribution of cord hysteresis to predicted rolling loss, the structural effects of the cord on the rubber stress-strain behavior are included and will contribute to the tire rolling loss by affecting the stress-strain cycle of the rubber.
Experimental work used to determine the parameters of the material model for specific compounds is outlined. Some example DIH parameters are listed by compound application.
The DIH theory within the Finite Element method is then used to predict rolling resistance for a specific tire design. The results are compared to experimental data taken using SAE J-1269. The value of the tire rolling resistance is predicted within a few percent. In addition, the sensitivities of the tire to changes in load and inflation pressure are predicted and they are found to compare favorably to the experimental results.
The DIH theory is implemented within a quasi-static FE model, and was not intended for use in dynamic applications such as the prediction of standing wave phenomena. While the quasi-static FE model used in this study can predict deformed shapes, stress distributions, and temperatures, there is presently no coupling between the thermal and mechanical models.
Theoretical Laws for Rear Steering in Four-Wheel Steering Vehicles, Seen from the Tire's Point of View
Authors: Salerno P. 
Published: June 2006

Abstract
Theoretical laws governing rear-wheel steering of a vehicle are developed from a linear model having two degrees of freedom. Such laws can aid in improving vehicle transient response. Examples are given of their use to show that the same handling behavior can be obtained in rear-steering vehicles that are equipped with variant tires as with front-steering vehicles equipped with standard tires. Tire variants studied were cornering stiffness and relaxation length. The laws also suggest ways to nullify lags in steering actuation.
Relationship Between Tire Tread Physical Properties and Tire Force and Moment Properties
Authors: Pottinger M. G. , Fairlie A. M. 
Published: June 2006

Abstract
Tire lateral force and aligning torque are the most significant determinants of automotive handling. Tread compound physical properties are important design parameters for determination of tire lateral force and aligning torque behavior.
This paper extends the published knowledge of the effects of tread compound physical properties on force and moment to cover the entire range of slip angles encountered in driving. Below 10 degrees slip angle lateral force increases with increasing compound stiffness and hysteresis. At and above 10 degrees slip angle there is a change in the general trend. In this range it appears that an optimal compound stiffness exists and that the hysteresis effect reverses. Aligning torque shows two distinctly different behaviors. One, like that governing lateral force in the general driving range, is valid below the peak of the aligning torque curve. The other, valid above the peak of the aligning torque curve, shows decreasing aligning torque with increasing tread stiffness and no hysteresis effect.