- Acoustic solutions
There are two main classifications for acoustic attenuation:
A reactive system reflects the sound waves from the noise source, which leads to cancellation of the sound waves. It can also contain a Helmholtz resonator that works in a narrow frequency band, which can be used for effective attenuation of engine firing frequencies.
A dissipative system can contain perforations and acoustic absorption material that convert acoustic energy into heat by absorbing the wave motion of the air particles in the porous materials.
The two principles can be combined to achieve attenuation at a broader frequency range. These are engineered for customer requirements.
The acoustic performance of silencers are evaluated by simulations of the transmission loss, which gives the silencer attenuation at a frequency range. These simulations are performed in COMSOL Multiphysics, where the main outputs are transfer matrix and transmission loss.
The simulations are validated on an acoustic flow rig at The Dinex Test Center.