Scale Modeling of Acoustic Scattering

Scale modeling has been used for architectural acoustics but use outside of that field appears to be minimal. Scale modeling theory is first reviewed and then some uses of scale modeling for acoustics are investigated. Scale modeling is first applied to determine the insertion loss of a barrier. A half scale model of the barrier is used and the insertion loss between the full and half scale models are compared. The barrier is also simulated using the finite element method with automatically matched layer boundary conditions. Simulation results compare well with measurement. Scale modeling is then applied to a more complicated geometry. A point source is placed above a structure with a deep cylindrical opening. Transfer functions are measured between positions outside and inside of the opening for both the full and 0.18 scale model with good correlation. Results are also compared to finite element simulation. The results suggest that scale modeling methods may be used to investigate small structures similar to that found in electronics equipment that are generally immeasurable due to the small size.