Finite difference time domain simulation for the brass instrument bore

Area of Science:

• Acoustics
• Computational physics
• Musical instrument science

Background:

• Accurate simulation of acoustic wave propagation in musical instruments is crucial for design and analysis.
• Existing methods often subdivide instrument bores, potentially limiting accuracy.
• Modeling viscothermal and radiation losses in the time domain presents significant challenges.

Purpose of the Study:

• To develop and present interleaved finite difference time domain (FDTD) methods for simulating acoustic bore dynamics.
• To model viscothermal and radiation losses within an acoustic tube in the time domain.
• To compare numerical simulations of input impedances with experimental measurements for brass instruments.

Main Methods:

• Utilized an impedance formulation of wave propagation in an acoustic tube.
• Developed interleaved finite difference time domain (FDTD) methods.
• Treated the entire acoustic bore, including mouthpiece and bell, as a single unit, avoiding segmentation into smaller units.
• Performed numerical simulations of input impedances.

Main Results:

• Successfully simulated the dynamics of the acoustic bore, incorporating viscothermal and radiation losses.
• The novel FDTD approach, treating the bore as a unit, demonstrated effectiveness.
• Numerical simulations of input impedances showed good agreement with measurements for various brass instruments.

Conclusions:

• The developed interleaved FDTD methods provide a robust framework for simulating acoustic bore dynamics.
• Modeling the entire bore as a unit offers an advantage over segmented approaches for brass instruments.
• This method facilitates accurate prediction of input impedances, aiding in instrument design and analysis.