Adjoint method to compute non-geometric sensitivities in time-dependent compressible flows.

• Ano de defesa: 2021
• Autor(a) principal: Cato, Arthur Shiniti
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Adjoint method; Aerodinâmica; Aerodynamics; Compressible flow; Computational fluid dy namics; Dinâmica dos fluidos computacional; Escoamento compressível; Método adjunto; Sensibilidades; Sensitivities
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/3/3150/tde-11012022-095516/

Sensitivity gradients are essential for many of the aerodynamic optimization methods.In particular, the information about the derivatives of functionals (usually related to the lift, drag, pressure distribution etc.) with respect to the boundary conditions allows one to determine regions of optimal operation. The present work studies the adjoint method in its continuous formulation and its application to time-dependent compressible flows;the method is used to compute sensitivities related to the control parameters imposed on the permeable boundaries. The adjoint equations and their boundary conditions are developed to establish a well-posed problem. It is used the characteristic formulation and the complete Riemann problem. The equations are solved by discretizing the spatial domain a finite volume method and the temporal integration is based on a 5-step Runge-Kutta scheme and second order of precision. Finally, the gradient of the function of merit is computed with respect to the parameters imposed at the boundaries for some examples.