Active Noise Cancellation (ANC) technology is widely used in automobiles to reduce engine harmonic noise [3]. ANC systems require one or more microphones mounted in the cabin to monitor the harmonic n....
Blower is one of the main noise sources of fuel cell vehicle. In this paper, a narrowband active noise control (ANC) model is established based on adaptive notch filter (ANF) to control the high-frequ....
Current powertrain active noise control (ANC) systems are not sufficient enough to track the fast engine speed variations, and yield consistent convergence speeds for individual engine order such that....
An important trend among vehicle NVH engineers is the production of attractive engine acceleration sound quality for the enhancement of a vehicle's image and performance. In addition, customers have i....
How to decrease noise and vibration exposure has been of interest for many years. Empirical data have indicated that too high dose values can create multiple problems to a human body - often severe. S....
In order to reduce high-frequency harmonic noise produced by the blower in the auxiliary system of a fuel cell vehicle (FCV), a narrowband active noise control (ANC) method instead of conventional pas....
Random vibration control systems produce a PSD plot by averaging FFTs. Modern controllers can set the Degrees of Freedom (DOF), which is a measure of the amount of averaging to use to estimate the PSD....
Active vibration control is the most effective method used for suppressing vibrations from external sources. This paper presents the particle swarm optimization (PSO) algorithm to search about the opt....
In the present study by the University of Idaho Clean Snowmobile Challenge (UICSC) team, the necessity, history, and research of noise reduction strategies in two-stroke snowmobile exhaust is presente....
Five parameters are often used in acoustic modeling of porous absorption material, which are air flow resistivity σ, porosity φ, tortuosity α∞, viscous and thermal characteristic lengths Λ and Λ′. The....
Both vehicle roof systems and vehicle door systems typically have viscoelastic material between the beams and the outer panel. These materials have the propensity to affect the vibration decay time an....
Test standards are essential for evaluating the performance of a product properly and for developing a data base for the product. This paper discusses various standards that are available for determin....
In automotive noise control, the hood liner is an important acoustic part for mitigating engine noise. The random incidence absorption coefficient is used to quantify the component level acoustic perf....
A comprehensive and systematic investigation of the acoustical performance of carbon-nanotube-enhanced polyurethane (PU) foams was performed. The complete foam making process was carried out carefully....
The ability of various plasticizers to impact the vibration damping properties of polyvinyl chloride (PVC) plastisols was investigated. A material must have good viscoelastic properties in order for i....
A novel porous metallic foam has been studied in this work. This composite material is a mixture of resin and hollow spheres. It is lightweight, highly resistive to contamination and heat, and is capa....
Over the past decade damping materials have contributed major improvements to passenger comfort. Noise Vibration and Harshness (NVH) engineers have further shaped material specifications to reflect ke....
Acoustic material testing is becoming increasingly relevant to engineers, designers and manufacturers from a broad range of industries. This paper presents comparisons between material absorption meas....
Acoustic performance of auto interiors is definitely important to control the NVH (noise, vibration, and harshness) performance inside a vehicle, and it is determined by the material parameters, such ....
Experimental measurements of tire tread band vibration have provided direct evidence that higher order structural-acoustic modes exist in tires, not just the well-known fundamental acoustical mode. Th....
