Abstract
As a matter of fact, an industry quantum leap for a vehicle improvement is represented by the competitive advantage" in the market. Especially nowadays where the market is characterised either by an amplification of the geographical areas of commercial interest, or by the reduction of demand and from a strong trend to technological innovation.
To satisfy the customer requirements is the main goal: a car is defined comfortable also by the noise level transmitted inside cabin and often this is one of the most valuable criteria for vehicle quality assessment. Consequently there is a general attention to design criteria that aim to improve the structural-acoustic behaviour in such a way to withstand the increasingly restrictive market standards. The actual horizon is to optimise all those components of chassis and body in white that contribute to noise generation inside the car.
In order to simplify such process, we are trying to decompose the target of vehicle acoustic attenuation into the attenuation for the components, in such a way we can focus structural modifications where seem to be a sore spot.
In this work, we intend to develop and apply a numerical procedure calculating a transmission loss in a vehicle component assessment based on a synergetic and integrated use of Finite Element (FEM) and Boundary Element (BEM) theories. The BEM technique is not so efficient to simulate the dynamical structure response thats why we ought to use FEM technique. On the other hand, with FE method is very difficult to simulate the anechoic chamber (infinite field), here comes an integrated approach for all the simulation. In the test case presented such procedure is applied to predict the transmission loss of a steel panel whose properties were previously measured by experimental tests in an anechoic-reverberant room. The panel structural behaviour is assessed by a FEM analysis and the resulting normal velocities are then imposed as boundary conditions for a BEM analysis of the transmitted noise field.