Vibration & sound power reduction of a thin plate-like structure excited by complex inputs

Vibration & sound power reduction of a thin plate-like structure excited by complex inputs

Many engineering structures are composed of plates and plate-like components, such as the outer casing of a washing machine, printed circuit boards (PCBs) in electronic devices, the ship hull and deck. These structures are vulnerable to complex inputs, combination of force and moment components, from vibrational sources such as motors, pumps, and collision between parts. The resulting vibration and noise emissions jeopardize the integrity of the engineering structure. Yonsei research team led by Professor No-Choel Park in the school of Mechanical Engineering proposed a new method for reducing the vibration and sound radiation of a thin plate excited by complex input sources.

A set of new formulas for the sound radiation of baffled and unbaffled plates are derived by substituting the moment components of the plates with the equivalent couples using finite difference analysis. This approach allows to calculate sound power purely by the input location and amplitude of each component. Thus, it enables faster, more accurate calculations than the existing methods such as the average radiation efficiency analysis and the radiation mode analysis. The results of the research were published in Journal of the sound and vibration with the title “Calculation and reduction of sound radiation from a thin plate structure excited by complex inputs”.