A computational methodology for two-dimensional fluid flows

TL;DR

This paper introduces a weighted residual collocation method with dyadic mesh refinement for simulating 2D fluid flows, demonstrating high accuracy and efficiency in natural convection and shear-driven flows.

Contribution

It develops a novel iterative interpolation scheme for basis functions in 2D meshes, improving accuracy and computational speed in fluid flow simulations.

Findings

Accurately resolves shear layers and energy conservation.

Achieves linear CPU time speedup with larger time steps.

Successfully simulates natural convection with energy transfer.

Abstract

A weighted residual collocation methodology for simulating two-dimensional shear-driven and natural convection flows has been presented. Using a dyadic mesh refinement, the methodology generates a basis and a multiresolution scheme to approximate a fluid flow. To extend the benefits of the dyadic mesh refinement approach to the field of computational fluid dynamics, this article has studied an iterative interpolation scheme for the construction and differentiation of a basis function in a two-dimensional mesh that is a finite collection of rectangular elements. We have verified that, on a given mesh, the discretization error is controlled by the order of the basis function. The potential of this novel technique has been demonstrated with some representative examples of the Poisson equation. We have also verified the technique with a dynamical core of two-dimensional flow in primitive variables. An excellent result has been observed-on resolving a shear layer and on the conservation of the potential and the kinetic energies with respect to previously reported benchmark simulations. In particular, the shear-driven simulation at CFL = 2.5 (Courant-Friedrichs-Lewy) and $\mathcal Re = 1\,000$ (Reynolds number) exhibits a linear speedup of CPU time with an increase of the time step, $Delta t$. For the natural convection flow, the conversion of the potential energy to the kinetic energy and the conservation of total energy is resolved by the proposed method. The computed streamlines and the velocity fields have been demonstrated.