| 摘要 |
PURPOSE:To improve fidelity by providing a constitution wherein the parts intersecting the profiles of the front and rear edges of the contact parts of tread-on and kick-out side edges at a unit time are made to be sound sources, the waveforms of the sounds are determined in consideration of phases, and the sounds having the waveforms which are computed along the entire surface of a tread are generated. CONSTITUTION:A tread pattern is expressed on an x-y plane with two-dimensional digital data so that a tread-on side edge 28 and a kick-out side edge 30 can be distinguished. Profiles 40 and 42 of the front edge and the rear edge of a footprint 22 are expressed with functions. The tire is moved on a unit distance in a unit time DELTAt. Sounds are generated at the parts where the edge 29 intersects the profile 40 and the edge 30 intersects the profile 42. General expressions for expressing the waveforms of the generated sounds are obtained. The conditions such as the sound-pressure levels, the attenuation coefficients, the frequencies and phase differences obtained by the experiment are added, and the waveforms of the sounds are determined. The waveforms are expressed on the x-y plane. The audible sound is generated based on the synthesized value of the waveforms on the x-y plane along the entire surface of the tread. Thus, the synthesized sound in high fidelity of the tire noises for all sizes, tread patterns and speeds is obtained, and the estimated evaluation can be performed. |
