EVENTO
Drag minimization in compressible flows
Tipo de evento: Seminário LNCC
A framework for shape sensitivity analysis of drag functional of an obstacle in wind tunnel is presented. First, an exemple of semilinear elliptic equation is considered. Material and shape derivatives of the solutions are defined and characterised. The associated shape functional is given by a linear form defined on the boundary. The shape gradient of the functional is obtained in two equivalent forms, the first is a distributed expression depending on the material derivatives, the second one is a boundary expression depending on the shape derivatives. The relation between the equivalent forms can be investigated by singular limit procedure, from the volume integrals to the boundary integrals, the passage is performed in the sense of measures.In the second part of the talk the proposed procedure is applied to compressible Navier-Stokes equations in bounded domains. The drag functional is introduced, and its shape derivative is obtained. The singular limit procedure is justified and the boundary expression of the shape gradient is presented. In particular, it is shown that the geometrical part of the shape gradient is null, therefore the solution to the adjoint equations is required in order to obtain nontrivial steepest descent direction for the drag minimization. Numerical results in two spatial dimensions are also presented.
Data Início: 13/04/2009 Hora: 14:00 Data Fim: Hora: 15:30
Local: LNCC - Laboratório Nacional de Computação Ciêntifica - Auditorio A
Comitê Organizador: Jan Sokolowski - Université de Lorraine, Institute Élie Cartan, France - CNRS,INRIA -
Apoio Financeiro: CAPES/COFECUB