Introduction to Acoustics (Part 2)

Week 1. Radiation – Breathing & Trembling SphereProblem

- What happensif we have a certain discontinuity that is a function of three spatialvariables (e.g. x,y,z for Cartesian coordinate)?

- What are theradiation characteristics of a breathing sphere, which is assumed to vibrateomni-directionally with equal magnitude?

- What is thedifference between a breathing sphere and a trembling sphere, which vibrates ina certain direction with a uniform velocity?

Week 2. Radiation – Baffled Piston & Finite VibratingPlate Problem

- How can wegenerate sound? By the fluctuation of fluid particles or the vibration ofstructures? How are they related?

- How can weunderstand the radiation of a finite vibrating plate? Can we assume this plateas numerous vibrating pistons?

 Week 3. Scattering& Diffraction / Kirchhoff-Helmholtz Equation

- How can weexpress the wave propagation when it is reflected due to the presence of discontinuitiesin space?

- How can weexplain the circumstances under which we can hear sound but cannot see thesound source?

- What is the relationbetween the wavelength and the diffraction?

Week 4. Wave Propagation in Space / Reverberation Period and its DesignApplication

- If there aredifferent types of impedance distribution in space, how can we explain thepropagation characteristics?

- How can weacoustically define ‘large’ or ‘small’ space’? Is it related to the frequency?

- Is there anymeasure that can represent the characteristics of the space?

Week 5. WavePropagation in Space / Duct Acoustics

- How can weexpress the sound field that is neither fully diffuse field nor only a directfield?

- When the sizeof the space is small relative to wavelength, what happens to the propagationof sound?

- When thelength of one direction is significantly greater than the cross-sectionaldirection of the space, how does the wave propagate with respect to itswavelength?