Influence of Tire Air-borne Noise on Vehicle Loudness Predicted during Design Phase Based on Hybrid Internal Noise Contribution Model 2012-36-0635

The development of new technologies that reduce engine size and improve performance, combined with the introduction of hybrid and electric vehicles, make tire noise critically important for the new generation of automobiles. Tire noise transmission into the passenger compartment can be classified as either air-borne or structure-borne sound. Both of these mechanisms are very complex to predict because tires are highly non-linear, subject to large static, dynamic and centrifugal loads; they suffer from impact, stick and slip forces; and the pumping of air in the tire grooves is complicated. Customers today demand more sophistication of products in terms of interior noise; thus, sound quality metrics have earned an important role during the design phase allowing human perception of noise to be predicted and improved with reduced cost in a way that addresses consumer preferences. Of the various metrics, loudness has been shown to be the most important metric due to consideration of masking effects on human hearing. This paper discusses global loudness assessment of a vehicle during its design phase for two different types of tires through a hybrid internal noise contribution model with the following inputs: i - powertrain forces (surrogate data); ii - tire radiated noise (measured from a carryover vehicle through of a chassis roll dynamometer within a hemi-anechoic chamber), iii - noise transfer functions (simulated using FEM), iv - acoustic noise reduction functions (simulated using SEA).