952 research outputs found

    Schwarz alternating domain decomposition approach for the solution of mixed heat convection flow problems based on the method of approximate particular solutions

    Get PDF
    The incompressible two-dimensional Navier-Stokes equations including thermal energy balance equation are solved by the recently developed Method of Approximate Particular Solutions (MAPS). In a previous authors’ work this method was implemented to solve the two-dimensional Stokes equations by employing the pressure and velocity particular solutions obtained by Oseen’s decomposition with the Multiquadric (MQ) RBF as non-homogeneous term. A pressure-velocity linkage strategy is not required since the pressure particular solutions are obtained from the velocity ones. In the present contribution, the Navier-Stokes equations with Boussinesq approximation are solved by linearizing the convective term in a Picard iterative scheme. With the velocity values obtained at each of the Picard iterations, the energy conservation equation is solved by the MAPS by approximating temperature with the particular solutions of a Poisson problem with the MQ as a forcing term. With the aim of improving the computational efficiency of the global strategy, the two-dimensional domain is split into overlapped rectangular subdomains where the Schwarz Alternating Algorithm is employed to find a solution by using velocity and temperatures values from neighbouring zones as boundary conditions. The mixed convection lid-driven cavity flow problem is solved for moderate Reynolds and low Richardson numbers with the aim of validating the proposed method

    Coupling Lattice Boltzmann and Molecular Dynamics models for dense fluids

    Full text link
    We propose a hybrid model, coupling Lattice Boltzmann and Molecular Dynamics models, for the simulation of dense fluids. Time and length scales are decoupled by using an iterative Schwarz domain decomposition algorithm. The MD and LB formulations communicate via the exchange of velocities and velocity gradients at the interface. We validate the present LB-MD model in simulations of flows of liquid argon past and through a carbon nanotube. Comparisons with existing hybrid algorithms and with reference MD solutions demonstrate the validity of the present approach.Comment: 14 pages, 5 figure

    Spectral methods for CFD

    Get PDF
    One of the objectives of these notes is to provide a basic introduction to spectral methods with a particular emphasis on applications to computational fluid dynamics. Another objective is to summarize some of the most important developments in spectral methods in the last two years. The fundamentals of spectral methods for simple problems will be covered in depth, and the essential elements of several fluid dynamical applications will be sketched
    • …
    corecore