Use of SEA to Model the Sound Field in Large Acoustic Spaces

ABSTRACT: The problem of predicting the sound pressure level distribution inside a large acoustic space due to one or more sound sources is examined using a development of Statistical Energy Analysis (SEA). The resulting model may be applied to predict the sound field inside an industrial workroom. The prediction method is based on a separate treatment of the direct and reverberant sound fields. The direct sound field is dealt with by assuming free-field propagation, with the application of corrections such as barrier theory as required. The reverberant field is analysed using the SEA framework with the power input corrected for energy lost at the first reflection. The total sound pressure level at any receiver point is given as the sum of the direct and reverberant fields. Measurements made in a workroom using experimental SEA methods, with the acoustic space considered as being divided into three distinct subsystems, demonstrated that the presence of a direct field can also significantly affect the experimental SEA procedure. Comparing measured and theoretically predicted SEA parameters, it is found that the coupling loss factors are in good agreement, but the damping loss factors estimated from published absorption coefficients for the surfaces and fittings agreed less well with the measured data