Improving the Acoustic Behavior of the Housing of Automatic Transmission of N2 Category Vehicle Based on the Method of Modal Representation of a Dynamic System

Abstract

There is a global tendency nowadays in the development of transport vehicles to ensure high safety, energy efficiency and comfort, characterized primarily by ergonomic and vibroacoustic indicators. This forces engineers and scientists to constantly strive to reduce a noise level emitted by both the vehicle as a whole and individual units and systems. The paper is a continuation of a series of articles devoted to the development of a verified mathematical model of a promising automatic transmission (AT) for a N2 category vehicle, reliably characterizing its vibroacoustic behavior. The article represents the results of a computational and experimental study of the AT vibroacoustic behavior, including the stages of testing, processing and analysis of their results, verification of the computational model created in the Simcenter 3D software product, identification of the main sources of acoustic radiation and the development of proposals for its reduction. The vibroacoustic characteristics of the object of study are obtained, namely frequencies and corresponding acoustic pressure values, their localization on the AT housing is performed. The developed and verified AT model makes it possible to predict the level of vibration and acoustic radiation with satisfactory accuracy. Based on comparative evaluation modeling of various design modification options, the best ones are determined, which allow to obtain the minimum acoustic pressure level at the measurement points and neutralize the most significant forms of vibrations. The introduction of the developed scientifically-based technical solutions into the design made it possible to reduce the integral level of acoustic pressure in the entire range from 2 to 10 dBA.