CSE Community Seminar
April 11, 2025, 12-1PM
Conference Room 45-432 in Building 45
A Space-time Adaptive Higher-order Finite Element Method for Sonic Boom
Renato Trono Figueras
PhD Student, Department of Aeronautics and Astronautics, MIT
Abstract:
The ability to accurately predict sonic boom propagation from the nearfield of an aircraft to the ground is a key step in the broader objective of airplane shape optimization to reduce boom loudness. The talk describes a loudness-based adaptive, higher-order finite element method to solve the boom propagation problem. Unlike time-marching schemes typically used in this problem, the space-time method described allows fully-unstructured mesh adaptation and thus a more efficient usage of degrees of freedom. The boom propagation is modeled using the augmented Burgers system of equations, including effects of thermoviscous diffusion, species relaxation, a stratified atmosphere, and ray tube area variation. The equations are solved using an adjoint-consistent Continuous Galerkin type discretization, and a PDE-based shock wave sensor is used to add artificial viscosity in shock areas, allowing to have better numerical stability. Furthermore, the mesh is automatically adapted based on output error, with the output being the loudness perceived at ground. For this, the output error is estimated employing the dual weighted residual (DWR) method, with a correction accounting for the addition of artificial viscosity. The framework is applied to a practical case, with particular focus on the ground pressure signal and its resulting loudness metric. Results show how the space-time adaptive approach allows for a significant reduction in degrees of freedom needed and highlight the benefits of a higher-order method, as quadratic solutions converge the loudness metric faster than linear solutions.
April 11, 2025, CSE Community Seminar
Renato Trono Figueras
PhD Student,
Department of Aeronautics and Astronautics, MIT