Airborne path attenuation of partial enclosures: Simulation and sensitivity study

Partial enclosures are a very common way to reduce noise emissions from machinery. However, partial enclosures exhibit complex acoustic behavior that is difficult to predict. The boundary element method (BEM) was used to predict the insertion loss and was compared to measurement with good agreement. After validating the model, a sensitivity study was conducted. Factors investigated included enclosure size, opening size, amount of absorption coverage, absorption location, and the relationship between the source directivity and the opening location. It is notable that insertion loss was most sensitive to opening size and absorption coverage.