The purpose of this paper is to show benefits of deflated preconditioned conjugate gradients (CG) in the solution of transient, incompressible, viscous flows coupled with…
The purpose of this paper is to show benefits of deflated preconditioned conjugate gradients (CG) in the solution of transient, incompressible, viscous flows coupled with heat transfer.
This paper presents the implementation of deflated preconditioned CG as the iterative driver for the system of linearized equations for viscous, incompressible flows and heat transfer simulations. The De Sampaio-Coutinho particular form of the Petrov-Galerkin Generalized Least Squares finite element formulation is used in the discretization of the governing equations, leading to symmetric positive definite matrices, allowing the use of the CG solver.
The use of deflation techniques improves the spectral condition number. The authors show in a number of problems of coupled viscous flow and heat transfer that convergence is achieved with a lower number of iterations and smaller time.
This work addressed for the first time the use of deflated CG for the solution of transient analysis of free/forced convection in viscous flows coupled with heat transfer.
The organization of events in public spaces in the cities of Oporto, Vila Nova de Gaia (both in Portugal), and Barcelona (Spain) led us to propose a classification of…
The organization of events in public spaces in the cities of Oporto, Vila Nova de Gaia (both in Portugal), and Barcelona (Spain) led us to propose a classification of thematic cities. The conclusions are the result of social representations of organizers and sponsors in the three cities and, thus, it is a qualitative study carried out in research Ph.D. in Sociology at the Faculty of Letters of the University of Oporto. We propose the presentation of some events organized in three public spaces – Aliados Avenue in Oporto, Cais de Gaia’s waterfront in Vila Nova de Gaia, and Ramblas in Barcelona – to make its framing in terms of objectives, motivations, and public. We also appealed to the social representations of interviewees to evaluate the quality and structure of public spaces in the two cities in the metropolitan area of Oporto in comparison with the Catalan city. Finally, we propose the typification of the three cities according to the features presented throughout the chapter.