Wedge and eggbar shoes change the pressure distribution under the hoof of the forelimb in the square standing horse

Abstract A tire slips circumferentially on the rim when subjected to a driving or braking torque greater than the maximum tire-rim frictional torque. The balance of the tire-rim assembly achieved with weight attachment at certain circumferential locations in tire mounting is then lost, and vibration or adverse effects on handling may result when the tire is rolled. Bead fitment refers to the fit between a tire and its rim, and in particular, to whether a gap exists between the two. Rim slip resistance, or the maximum tire-rim frictional torque, is the integral of the product of contact pressure, friction coefficient, and the distance to the wheel center over the entire tire-rim interface. Analytical solutions and finite element analyses were used to study the dependence of the contact pressure distribution on tire design and operating attributes such as mold ring profile, bead bundle construction and diameter, and inflation pressure, etc. The tire-rim contact pressure distribution consists of two parts. The pressure on the ledge and the flange, respectively, comes primarily from tire-rim interference and inflation. Relative contributions of the two to the total rim slip resistance vary with tire types, depending on the magnitudes of ledge interference and inflation pressure. Based on the analyses, general guidelines are established for bead design modification to improve rim slip resistance and mountability, and to reduce the sensitivity to manufacturing variability. An iterative design and analysis procedure is also developed to improve bead fitment.

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One-Dimensional Contact Pressure Distribution of Radial Tires in Motion

Tire Science and Technology ◽

10.2346/1.2137498 ◽

1995 ◽

Vol 23 (2) ◽

pp. 116-135 ◽

Cited By ~ 9

Author(s):

H. Shiobara ◽

T. Akasaka ◽

S. Kagami ◽

S. Tsutsumi

Keyword(s):

Pressure Distribution ◽

Contact Pressure ◽

Experimental Studies ◽

Rolling Resistance ◽

Leading Edge ◽

Forward Direction ◽

Contact Pressure Distribution ◽

Support Ring ◽

One Dimensional ◽

Lowered Pressure

Abstract The contact pressure distribution and the rolling resistance of a running radial tire under load are fundamental properties of the tire construction, important to the steering performance of automobiles, as is well known. Many theoretical and experimental studies have been previously published on these tire properties. However, the relationships between tire performances in service and tire structural properties have not been clarified sufficiently due to analytical and experimental difficulties. In this paper, establishing a spring support ring model made of a composite belt ring and a Voigt type viscoelastic spring system of the sidewall and the tread rubber, we analyze the one-dimensional contact pressure distribution of a running tire at speeds of up to 60 km/h. The predicted distribution of the contact pressure under appropriate values of damping coefficients of rubber is shown to be in good agreement with experimental results. It is confirmed by this study that increasing velocity causes the pressure to rise at the leading edge of the contact patch, accompanied by the lowered pressure at the trailing edge, and further a slight movement of the contact area in the forward direction.

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Analysis of the Contact Deformation of a Radial Tire with Camber Angle

Tire Science and Technology ◽

10.2346/1.2137494 ◽

1995 ◽

Vol 23 (1) ◽

pp. 26-51 ◽

Cited By ~ 5

Author(s):

S. Kagami ◽

T. Akasaka ◽

H. Shiobara ◽

A. Hasegawa

Keyword(s):

Pressure Distribution ◽

Contact Pressure ◽

Contact Region ◽

Contact Deformation ◽

Contact Pressure Distribution ◽

Radial Tire ◽

Ring Model ◽

Camber Angle ◽

Contact Free ◽

Good Agreement

Abstract The contact deformation of a radial tire with a camber angle, has been an important problem closely related to the cornering characteristics of radial tires. The analysis of this problem has been considered to be so difficult mathematically in describing the asymmetric deformation of a radial tire contacting with the roadway, that few papers have been published. In this paper, we present an analytical approach to this problem by using a spring bedded ring model consisting of sidewall spring systems in the radial, the lateral, and the circumferential directions and a spring bed of the tread rubber, together with a ring strip of the composite belt. Analytical solutions for each belt deformation in the contact and the contact-free regions are connected by appropriate boundary conditions at both ends. Galerkin's method is used for solving the additional deflection function defined in the contact region. This function plays an important role in determining the contact pressure distribution. Numerical calculations and experiments are conducted for a radial tire of 175SR14. Good agreement between the predicted and the measured results was obtained for two dimensional contact pressure distribution and the camber thrust characterized by the camber angle.

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Measurement and Visualization of the Contact Pressure Distribution of Rubber Disks and Tires

Tire Science and Technology ◽

10.2346/1.2137506 ◽

1995 ◽

Vol 23 (4) ◽

pp. 238-255 ◽

Cited By ~ 16

Author(s):

E. H. Sakai

Keyword(s):

Pressure Distribution ◽

Contact Pressure ◽

Contact Area ◽

Light Absorption ◽

Lateral Force ◽

Contact Pressure Distribution ◽

High Definition ◽

The Road ◽

Close Relationship ◽

Processing Techniques

Abstract The contact conditions of a tire with the road surface have a close relationship to various properties of the tire and are among the most important characteristics in evaluating the performance of the tire. In this research, a new measurement device was developed that allows the contact stress distribution to be quantified and visualized. The measuring principle of this device is that the light absorption at the interface between an optical prism and an evenly ground or worn rubber surface is a function of contact pressure. The light absorption can be measured at a number of points on the surface to obtain the pressure distribution. Using this device, the contact pressure distribution of a rubber disk loaded against a plate was measured. It was found that the pressure distribution was not flat but varied greatly depending upon the height and diameter of the rubber disk. The variation can be explained by a “spring” effect, a “liquid” effect, and an “edge” effect of the rubber disk. Next, the measurement and image processing techniques were applied to a loaded tire. A very high definition image was obtained that displayed the true contact area, the shape of the area, and the pressure distribution from which irregular wear was easily detected. Finally, the deformation of the contact area and changes in the pressure distribution in the tread rubber block were measured when a lateral force was applied to the loaded tire.

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Experimental Study of Flow Control Over a Standard Road Vehicle Using Plasma Actuator

Mechanics and Mechanical Engineering ◽

10.2478/mme-2018-0083 ◽

2020 ◽

Vol 22 (4) ◽

pp. 1047-1060

Author(s):

S. Shadmani ◽

S. M. Mousavi Nainiyan ◽

R. Ghasemiasl ◽

M. Mirzaei ◽

S. G. Pouryoussefi

Keyword(s):

Flow Control ◽

Pressure Distribution ◽

Drag Force ◽

Separated Flow ◽

Plasma Actuator ◽

Road Vehicle ◽

Slant Angle ◽

Total Drag ◽

Slant Surface ◽

Ahmed Body

AbstractAhmed Body is a standard and simplified shape of a road vehicle that's rear part has an important role in flow structure and it's drag force. In this paper flow control around the Ahmed body with the rear slant angle of 25° studied by using the plasma actuator system situated in middle of the rear slant surface. Experiments conducted in a wind tunnel in two free stream velocities of U = 10m/s and U = 20m/s using steady and unsteady excitations. Pressure distribution and total drag force were measured and smoke flow visualization carried out in this study. The results showed that at U = 10m/s using plasma actuator suppress the separated flow over the rear slant slightly and be effective on pressure distribution. Also, total drag force reduces in steady and unsteady excitations for 3.65% and 2.44%, respectively. At U = 20m/s, using plasma actuator had no serious effect on the pressure distribution and total drag force.

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