Global feedforward active noise control in vibro-acoustic cavities without increasing structural vibrations.

Area of Science:

• Vibro-acoustic systems
• Active noise control
• Structural dynamics

Background:

• Interior noise in cavities arises from acoustic and structural disturbances.
• Optimizing actuators reduces acoustic potential energy but may increase structural kinetic energy.
• Existing methods lack control over structural kinetic energy during noise reduction.

Purpose of the Study:

• To develop a feedforward active noise control technique for vibro-acoustic cavities.
• To ensure noise reduction does not increase the kinetic energy of the cavity structure.
• To formulate the problem as a constrained minimization to balance acoustic and kinetic energy.

Main Methods:

• Formulation of the problem as a constrained minimization problem.
• Minimizing acoustic potential energy subject to a constraint on kinetic energy.
• Utilizing a penalty function method for solving sequential unconstrained problems.

Main Results:

• Numerical studies demonstrate favorable outcomes in reducing both acoustic potential and kinetic energy.
• The proposed method effectively controls interior noise without exacerbating structural vibrations.
• Validation on a car-like cavity confirms efficacy for single- and multi-tonal noise.

Conclusions:

• The developed feedforward technique successfully reduces interior noise while constraining kinetic energy.
• This approach offers a balanced solution for active noise control in vibro-acoustic systems.
• The penalty function method provides an effective means to solve the constrained optimization problem.