Recent Enhancements to Modeling Sonic Boom Propagation using Augmented Burgers’ Equation

Speaker: Sriram Rallabhandi, Computational Aerosciences Branch, NASA Ames Research Center
July 27, 2023

Presentation

Abstract

Sonic boom propagation through the atmosphere is modeled with an augmented Burgers’ equation which includes nonlinearity and loss mechanisms. This work details updated discretizations of the governing equations which are fully conservative and duality preserving. Adjoint equations, for all the mechanisms involved, are re-derived and implemented using adjoint consistent discretizations. Computation of loudness metrics is performed using digital filters. The updated implementation is demonstrated and compared against the previous formulation for selected cases, and the differences are documented and discussed. The improved discretization results in faster mesh convergence of the loudness metrics and substantially decreases runtime. In addition, the adjoint solutions provide mesh-converged gradients which are free from spurious oscillations.

This work is supported by NASA ARMD’s Commercial Supersonic Technology (CST) project.

Biography

Sriram Rallabhandi is an Aerospace Engineer with an MS & Ph.D. from Georgia Tech and a BS from the Indian Institute of Technology, Kanpur, India. His primary research interests are computational/numerical methods applied to aircraft, specifically for sonic boom mitigation, MDO, applied aerodynamics and design optimization. He has several years of experience in the development of computational tools and methods for aiding in the analysis and design of aircraft concepts. He is the tech lead for the prediction and validation of tools (ProViT) tech challenge within the Commercial Supersonic Technology (CST) project and supports the LBFD project on the sonic boom analysis of the X-59 Quesst.

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