The growing trend in demand for vehicles with diesel engines, especially in Europe, is a result of consumer demand for vehicles that offer greater fuel economy. This trend is gaining attention in North America as well. However, diesel vehicles are notorious for their NVH issues including engine vibrations that reverberate through the passenger cabin and noise that transmit through windshields as both structure-borne noise and airborne noise.
Windshields, normally seen as the big hole in the front of the vehicle through which noise passes into the vehicle cabin, can be transformed to provide noise-mitigating properties by redesigning the PVB interlayer to reduce noise entering the vehicle. In essence, an acoustical windshield can help dissipate noises to a significant degree.
NVH testing was performed on vehicles with diesel engines and acoustical-grade windshields, and vehicles with diesel engines and windshields made with standard PVB. The testing results showed a significant improvement in cabin noise reduction with the acoustic-grade windshield.
The acoustic-grade windshield reduces specific additional power train noise on a diesel-powered vehicle by up to 6 dB and makes the vehicle quieter than the equivalent gasoline-powered vehicle with a standard PVB windshield. In addition, the use of an acoustic-grade windshield on diesel-powered vehicles significantly enhances the Z-Loudness, the Articulation Index, and the Sharpness measures.
The acoustic-grade windshield addresses and solves one of the major issues related to the use of diesel vehicles, increased noise in the passenger cabin, and serves to enhance the perception of these vehicles as not only fuel efficient, but as more quiet and, therefore, more comfortable and desirable to drive.