Panel Acoustic Contribution Analysis And Structure Optimization Of Tractor CAB

Nowadays the noise problem is getting more and more remarkable. As a result the tractor factory, in order to improve the market competitiveness, has to pay more attention to control the noise of production. How to predict the interior noise of tractor cab and to design tractor cab with low lever noise is a important research direction. In this paper, series of study on predict and analysis of low-frequency structure borne noise of the tractor cab have been done on the basis of theoretical analysis of the sound and vibration.First the structure geometric model of a tractor cab FT80 was established using FEM software ANSYS, then the finite element modal of the structure and acoustic were established based on the geometric model. Structure mode of the structure was computed in ANSYS and imported into acoustic analysis software LMS. Virtual Lab in which acoustic mode was computed and FEM vibro-acoustic coupling analysis was done. The acoustic response at the position of the ear of driver was predicted and the mode partition factor (MPF) of structure and acoustic to the response of cab was analyzed.Then based on the sensitivity idea, the acoustic sensitivity of the tractor cab was studied, from which the main reason of acoustic resonance in tractor cab is identified.As the main purpose is to reduce the noise level at driver ear, panel acoustic contribution analysis (PACA) and Modal Acoustic contribution analysis (MATV) was executed to analysis the different contribution of structure panels to the acoustic response at position of tractor's right ear. The main positive contribution panels and structure modal were successfully identified.According to the above results, the last part of this paper analyzed the influence of the damping, stiff of structure and absorb materials. Using different method the noise level at driver right ear was reduced.In this paper, a relatively systematic study of prediction and diagnosis of structure-brone noise interior of tractor cab is presented. The study provides a certain theoretical basis for reducing cab noise.