Methodology for Controlling Equipment Noise Behaviour

Abstract. Increasing the noise reduction requirements for both the users and the environment has led to an increasing need to control the noise and vibration (NV) behaviour of new equipment. This problem arises in practice in the form of various specific and often determining development contingencies: reduction in weight and size of structures, reduction in cost and design time and the external supply of components. For these reasons, optimising the noise and vibrations of equipment requires an overall methodological approach. The elaboration of such a methodology constitutes the object of this contribution. The methodology is first of all based on the principle of dividing up the overall behaviour of the equipment into a reduced number of situations and performances, which in turn are decomposed in terms of dominant contributions. Secondly, the control of the contributions is carried out within the framework of a pre-defined analysis along three main lines: establishing the behaviour criteria of the components, specifying these criteria to the suppliers and controlling and optimising the performance of the critical components. The main interest of this approach lies in the fact that it provides the manufacturers, before the designing stage, with a structured and specific overall schematic diagram of the main actions to be undertaken in relation to noise and vibrations (methodological sections), and enables a specific knowledge base to be drawn up during the development phase. The case study of the noise and vibration optimisation of the VAL208 metro is presented. By identifying and providing a detailed characterisation of all the main elements that need to be taken into consideration for NV optimisation, this case served as a basis for the elaboration of the methodology proposed