![]() ![]() Road noise is mainly below 500 Hz and occurs with vibration of the vehicle structure through the transfer path. Pattern noise is mainly associated with the shape of the tire tread pattern, is in the range of over 500 Hz, and is a phenomenon due to air. Strictly speaking, the latter should be called the vibro-dynamic noise and aerodynamic noise or vibro-acoustic noise and aeroacoustics noise. ![]() Generally, in acoustics, the difference between structure-borne and air-borne noise is the medium of transmission, but in terms of tire noise, the difference is sometimes focused on the noise generation mechanism, which is usually misused. The other is the exterior noise caused by only the air-borne path. Airborne noise is related to compression of the air trapped within the tread of the rolling tire. One is the interior noise due to structure-borne path and air-borne path. Generally, the major pneumatic tire noise is divided into two types. Therefore, optimal design of pattern shape is required to satisfy not only the noise performance but also other performances. In addition, because the pattern shape is associated with various tire performances such as groove wander, hydroplaning, and brake performance, it is an important design element. The pattern noise prediction method is important because it is difficult to change the shape and arrangement of the tire after they are determined in the beginning of the tire development process. For satisfying consumer demand on low tire noise, prediction systems for tire noise waveforms are necessary, and further elements for sound analysis and prediction steps of the process preceding the establishment of the design are also needed. Studies regarding optimal road texture and mixture design for noise abatement have been widely available in recent years. In this context, it is however of paramount interest to improve the tires, but also the road pavements. Tire-road noise is the main source of noise produced by a car and is a remarkably complex phenomenon resulting from the combination of airborne and structure-borne phenomena, where the source is provided by the contact between tire and pavement. As the number of electric vehicles increases, the reduction of tire noise becomes more important. Due to the development of automotive technology and the increased interest in environmental issues, many innovative noise reduction techniques for automotive engines have been studied, especially for the development of electric cars. Noise produced by cars is important not only inside but also outside. Eventually, using the prediction method from this study, we hope to reduce the time and cost spent on tire pattern design and verification. Finally, a sound quality index (SQI) of tire pattern noise was developed using the measured pattern noises and was applied to estimate the sound quality of pattern noise. The predicted waveform of pattern noise was validated with the waveforms of measured noise data. To predict the waveform of an actual pattern noise in the time domain, the impulse response of this transfer function was convolved by the scanned pattern input of tires. In this study, adaptive filter theory was applied to identify the transfer function between the grooves of patterns and measured acoustic data. However, this method has limitations because it does not consider the transfer function and precise mechanism of tire pattern noise. The conventional method of predicting tire pattern noise is to simply scan the pattern shape of tire and to analyze its spectrum. ![]() In pneumatic tire pattern design, the prediction technology of the tire pattern noise according to pattern shape design is important. The tire pattern noise depends on the tire itself and causes complex and unpredictable sounds. Identifying the cause of vehicle noise is a basic requirement for the development of low-noise vehicles. ![]()
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