Exterior Noise Emitted by Heavy Trucks: Analysis Methods & Reduction Technologies

Nowadays exterior noise emitted by heavy trucks represents a challenge for vehicle OEMs, test procedure implementation and reduction technologies. Shields applied to vehicle cabs, bulkheads and engine integrated elements and/or engine sound-proofing parts are used to reduce the exterior noise together with last generation diesel engines. Components size and characteristics, acoustic insulation and absorption properties represent important design variables optimized by structural and vibro-acoustic parametric analysis. Sound pressure and intensity experimental measurements, near field holography, NVH techniques are used to check the intervention result effectiveness in parallel with pass-by tests and component SEA and BEM model development. The most innovating technological expedients are illustrated as proposed by Rieter Automotive in this field.