Sumitomo Rubber Industries Limited

Sri Sports Limited

Akio Miyori

Masaki Shiraishi

Takahiro Sajima

Kazuhiro Fujisawa

Naoaki Iwasaki

Kiyohito Maruoka

The present invention is a method for tire rolling simulation comprising the steps of: setting a tire model by modeling a tire with the use of elements capable of numerical analysis; setting a road surface model including a road-surface matter model formed by modeling road-surface matter forming a road surface with the use of elements that can be numerically analyzed and can cause a volume change due to compression which is substantially permanent; and performing a tire rolling simulation by making the tire model get in contact with the road-surface matter model, thereby providing the tire model with rotating conditions, and conducting deformation calculations of the tire model and the road-surface matter model at minute time increment intervals.

Method for tire rolling simulation

A gas flow simulation method includes setting an imaginary object model such as a sphere model having at least one concavity, convexity, groove or projection formed thereon by means of a computer. A spatial part on a periphery of the imaginary object model is set. A surface of the imaginary object model and the spatial part is divided into a large number of blocks to form a large number of latticed divisions by lattice points. A gas flows to the imaginary object model from one direction of the spatial part. A motion element of a flow of the gas in the spatial part for each latticed division or for each latticed point is computed, with the gas flowing in the spatial part and passing along the surface of the imaginary object model. The flow of the gas on the periphery of the imaginary object model is simulated.

Gas flow simulation method

An object having a concavity on a surface thereof is formed by means of a computer. A part of the surface of the object including the concavity is extracted. A spatial part in contact with the extracted surface of the object is formed by dividing the extracted surface of the spatial part into blocks. A large number of lattice-shaped portions is formed by dividing the spatial part into lattices. In a simulation, a gas is flowed into the spatial part in one direction. The motion of the gas is computed discretely for each lattice-shaped portion at each slight time by the equation of continuity and the Navier-Stokes equation. Based on results of the computation, the motion of the gas is visualized by a visualizing program.

A heavy duty tire comprises a carcass ply turned up around a bead core in each bead portion to form a pair of turnup portions and a main portion, and a bead reinforcing layer disposed in the bead portion and comprising an axially outer part and an axially inner part, wherein under a 50 kPa state of the tire in which the tire is mounted on a standard rim and inflated to 50 kpa: the turnup portion inclines towards the carcass ply main portion at an angle of less than 90 degrees; the distance La of the end of the turnup portion from the radially outer side of the bead core is in a range of from 5 to 12 mm; the radial height Ho of the axially outer part is in a range of from 20 to 35 mm; the distance To of the end of the axially outer part from the axially outer surface of the bead portion is in a range of from 6 to 12 mm; and the ratio To/Ho of the distance To to the height Ho is in a range of from 0.25 to 0.5.

Heavy duty tire

A method of simulating a rolling tire and a simulator are disclosed, the simulating method comprises the steps of: dividing the tire into a tire body and a tread part therearound, wherein the tire body is defined as a toroidal part of the tire which is materially and geometrically the same or constant along the tire circumferential direction, and the tread part is defined as the remaining annular part around the tire body; modeling the tire body in finite elements; modeling the tread part in finite elements; combining the tread model with the body model to form a tire model; adjusting the beads of the tire model to a wheel rim on which the tire is mounted; contacting the tire model with a road model; moving the road model at predetermined time intervals relatively to the tire model, giving running conditions; obtaining information about the tire model as numerical data in time sequence; and processing the numerical data in time sequence to be outputted as a visible information. Preferably, the body model comprises models of the bead cores, rubber parts, and cord reinforcements each comprising a model of a cord ply and a model of topping rubber, wherein the cord ply is modeled in quadrilateral membrane elements defined as an orthotropic material, and the topping rubber is modeled in hexahedral solid elements.

Growing community of inventors

Kobe, Japan

Akio Miyori