TRANSIENT STATISTICAL ENERGY ANALYSIS: A TWO-SUBSYSTEM MODEL TO ASSESS THE VALIDITY OF USING STEADY-STATE COUPLING LOSS FACTORS FOR PLATE RADIATION

摘要

The aim of this paper is to assess the validity of incorporating steady-state coupling loss factors for sound radiation from plates in a Transient Statistical Energy Analysis (TSEA) model. A two-subsystem model is considered which corresponds to a physical experiment with an unbaffled aluminium plate with free boundaries that is coupled to a large reverberant room on both sides. To overcome the difficulty of accurately predicting the radiation efficiency below the critical frequency of the plate, Experimental Statistical Energy Analysis (ESEA) is used to determine the steady-state coupling loss factors for a variety of different damping conditions for both these subsystems. The measured coupling loss factors are then incorporated in a two-subsystem TSEA model for comparison with measured maximum sound pressure levels and the maximum vibration levels. For transient excitation this required a new approach to determine a time-varying power input into a structural subsystem. Good agreement is achieved between measurements and predictions.