Active force control of structure-borne sound based on robust optimization subjected to an irregular cavity with uncertainties

This paper proposes a novel method of structure-borne sound analysis and active force control, which combines interval mathematics and robust optimization theorems, to achieve vibration damping and noise reduction for enclosed cavity systems with bounded uncertainty. By introducing the interference principle of sound wave, responses under control can be obtained by solving finite element equations of structural–acoustic coupling systems. Through synthetical considerations of parameter dispersion in practice, the interval quantitative model, which only needs limited sample data, is defined, and the interval Taylor extension approach is employed to further determine boundary rules of responses of structural vibration and acoustic noise. On this basis, a new interval-oriented robust optimization framework is established to seek the optimal secondary force to simultaneously minimize nominal and radius levels of sound pressure indexes at concerned space and frequency domains. A complicated engineering example of the 3-D bomb cavity is eventually presented, in which numerical and experimental results can demonstrate the usage, validity and effectiveness of the developed methodology.