Continuous and Discrete Adjoints to the Euler Equations for Fluids

Autor:	Alauzet, Frederic, Pironneau, Olivier
Rok vydání:	2011
Předmět:	Computer Science - Computational Engineering Finance and Science Mathematics - Numerical Analysis Physics - Fluid Dynamics
Druh dokumentu:	Working Paper
Popis:	Adjoints are used in optimization to speed-up computations, simplify optimality conditions or compute sensitivities. Because time is reversed in adjoint equations with first order time derivatives, boundary conditions and transmission conditions through shocks can be difficult to understand. In this article we analyze the adjoint equations that arise in the context of compressible flows governed by the Euler equations of fluid dynamics. We show that the continuous adjoints and the discrete adjoints computed by automatic differentiation agree numerically; in particular the adjoint is found to be continuous at the shocks and usually discontinuous at contact discontinuities by both. Comment: 30 pages 16 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1104.1717 Zobrazit plný text záznamu View this record from Arxiv