ИССЛЕДОВАНИЕ И РАЗРАБОТКА ОЦЕНОЧНЫХ КРИТЕРИЕВ АКУСТИЧЕСКОГО КОМФОРТА АВТОТРАНСПОРТНЫХ СРЕДСТВ

Abstract

Ensuring the set level of acoustic comfort in passenger compartments of motor vehicles (hereinafter – MV) and low levels of external noise represents the important direction in their design and improvement. One of the important tasks in this process is the development of the objective criteria that characterize the attainable level of acoustic comfort of the developed construction of a vehicle. Well-known methods and objective criteria for assessment of acoustic comfort are characterized by limited load and high-speed modes of operation, complexity of interpretation and ranging of the obtained results, and insufficient correlation with results of the subjective expert opinion. The paper analyzes results of experimental studies of internal noise of 70 models of motor vehicles (cars) of the domestic and foreign manufacturers executed in road and bench test conditions. Road acoustic tests were carried out on public roads, moving with intensive acceleration, stabilized speeds, and motion with the engine switched off. Bench acoustic tests were carried out on motionless samples of motor vehicles in the conditions of a full-scale whirl tube and a big semi-anechoic acoustic chamber. In the course of analysis of the obtained results the researcher assesses statistical distribution of the studied parameters; the nature of their change depending on the load and high-speed modes of operation; chronological tendencies. The studied samples of MV are ranged into four categories of acoustic comfort in each of the studied modes of acoustic tests. The model of formation of a complex index of MV acoustic comfort has been developed based on the parameters of noise levels, levels of sound pressure at frequencies of motor harmonicas, and articulation indexes. Contribution of each of the acoustic parameters measured on various modes of tests is defined by empirical coefficients of weight. Objective criteria of ranging the acoustic parameters in various load and high-speed modes of operation can be used in technical requirements to design of the new and modernization of the existing models of MV. The complex index of acoustic comfort is offered to be applied for determination of competitiveness level and perfection of MV design within the target group of analogs.