Simulating fluids with a computer: Introduction and recent advances
In this article, I present recent methods for the numerical simulation of fluid dynamics and the associated computational algorithms. The goal of this article is to explain how to model an incompressible fluid, and how to write a computer program that simulates it. I will start from Newton laws "$F = ma$" applied to a bunch of particles, then show how Euler's equation can be deduced from them by "taking a step backward" and seeing the fluid as a continuum. Then I will show how to make a computer program. Incompressibility is one of the main difficulties to write a computer program that simulates a fluid. I will explain how recent advances in computational mathematics result in a computer object that can be used to represent a fluid and that naturally satisfies the incompressibility constraint. Equipped with this representation, the algorithm that simulates the fluid becomes extremely simple, and has been proved to converge to the solution of the equation (by Gallouet and Merigot).