Sonic boom propagation around a large building using a combined ray tracing/radiosity method

Area of Science:

• Acoustics
• Aerodynamics
• Environmental Science

Background:

• Supersonic flight over land is under scrutiny due to potential noise pollution.
• Understanding sonic boom behavior around structures is crucial for human impact assessment.
• Previous studies lacked detailed analysis of sonic booms interacting with complex building facades.

Purpose of the Study:

• To model and analyze the sound field of sonic booms around large structures.
• To compare simulation results with experimental data from NASA's SonicBOBS test.
• To evaluate the influence of facade complexity, absorption, and scattering on sonic boom propagation.

Main Methods:

• Utilized a combined ray tracing and radiosity method for sound field simulation.
• Modeled sonic booms interacting with large, complex building structures.
• Compared simulation outputs against measured data from the 2009 Sonic Booms on Big Structures (SonicBOBS) test.

Main Results:

• Simulations demonstrated general agreement with the experimental data from the SonicBOBS test.
• Facade complexity, absorption, and scattering coefficients were found to influence the sonic boom signature.
• Including diffuse reflections in the model did not significantly alter the sonic boom signature or improve comparison with measurements.

Conclusions:

• The combined ray tracing/radiosity model provides a viable method for simulating sonic booms around buildings.
• Diffuse reflections do not significantly impact sonic boom signatures for isolated buildings and are computationally expensive.
• Future modeling efforts for isolated structures can exclude diffuse reflections to optimize computational resources.