Short MaTx waves, about 5 mm, act as acoustical pores and reduce tyre/road noise. Macrotexture (MaTx) is partly a desired property and partly an undesired property. However, friction also depends on other surface properties, such as macro-texture. Typically, road agencies do not monitor mix directly, but indirectly by brake friction tests. The mix of the road material contributes to dry road surface friction. It relates to the surface of the binder, of the aggregate, and of contaminants such as rubber deposits from tires. Microtexture has wavelengths shorter than 0.5 mm. While vehicle suspension deflection and dynamic tire loads are affected by longer wavelength ( roughness), road texture affects the interaction between the road surface and the tire footprint. This model deepens knowledge on tyre/road interaction.Microtexture (MiTx) is the collaborative term for a material's crystallographic parameters and other aspects of micro-structure: such as morphology, including size and shape distributions chemical composition and crystal orientation and relationships Finally, experimental tyre/road noise and enveloped texture data obtained with the indenter algorithm have been used to elaborate a linear model that relates low and high frequency noise to texture one-third octave bands. Correlation patterns show that rolling noise can be separated in three main contributions: low, middle and high frequency noise. The first algorithm, proposed by Von Meier and based on the limitation of the second order derivative of the profile signal, shows poor correlation with high frequency noise, while the second algorithm, based on a novel method proposed by Sandberg and Goubert and called indenter method, enhances correlation with low frequency noise and preserves information at higher frequencies. Tyre deformation has also been addressed by analysing two already existing tyre envelopment algorithms. The present work studies the correlation between road texture and tyre/road noise from an experimental point of view, by analysing texture and noise spectra on ten different road surfaces. Several studies tried to find a correlation between road texture and broadband noise data, trying to provide guidelines for the development of acoustically optimised road surfaces. The main source of road traffic noise is tyre/road interaction thus, the use of low noise road surfaces represents an optimal solution for its mitigation. Road traffic noise is the most common source of environmental pollution in urban areas and therefore, the study of noise mitigation actions is fundamental for urban planning.
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