Early Attempts With A Square Lattice
In papers published in 1973 and 1976, Hardy, Pomeau and de Pazzis introduced the first Lattice Boltzmann model, which is called the HPP model after the authors. In this model, the lattice is square, and particles can move to any of the four sites whose cells share a common edge. Particles cannot move diagonally.
If two particles collide head-on, for example a particle moving to the left meets a particle moving to the right, the outcome will be two particles leaving the site at right angles to the direction they came in.
The HPP model lacked rotational invariance, which made the model highly anisotropic. This means for example, that the vortices produced by the HPP model are square-shaped.
Read more about this topic: Lattice Gas Automaton
Famous quotes containing the words early, attempts and/or square:
“It is not too much to say that next after the passion to learn there is no quality so indispensable to the successful prosecution of science as imagination. Find me a people whose early medicine is not mixed up with magic and incantations, and I will find you a people devoid of all scientific ability.”
—Charles Sanders Peirce (1839–1914)
“There is hardly an American male of my generation who has not at one time or another tried to master the victory cry of the great ape as it issued from the androgynous chest of Johnny Weissmuller, to the accompaniment of thousands of arms and legs snapping during attempts to swing from tree to tree in the backyards of the Republic.”
—Gore Vidal (b. 1925)
“Rationalists, wearing square hats,
Think, in square rooms,
Looking at the floor,
Looking at the ceiling.
They confine themselves
To right-angled triangles.”
—Wallace Stevens (1879–1955)