Sonic boom propagation in urban canyons using a combined ray tracing/radiosity method

Area of Science:

• Acoustics
• Urban planning
• Aerospace engineering

Background:

• Supersonic flight over land necessitates understanding sonic boom impacts on populations.
• Urban areas are particularly vulnerable due to high population density.

Purpose of the Study:

• To model sonic boom propagation in urban canyons.
• To investigate the influence of parameters like diffusion, arrival angle, building height, and canyon width on the urban sonic boom sound field.

Main Methods:

• A combined ray tracing and radiosity method was employed.
• The study simulated sonic boom interactions within urban canyon geometries.

Main Results:

• Without diffusion, sonic boom trends were inconsistent, with significant shadow zones and variable boom event reception.
• Diffuse reflections had the most substantial impact, altering signature shapes and reducing perceived loudness (PLdB).

Conclusions:

• Diffuse reflections are critical in shaping urban sonic boom characteristics.
• Managing reflections can mitigate the impact of sonic booms in cities.