In this section we discuss another significant HPJava application code. This code solves the Euler equations for inviscid fluid flow by a finite volume approach. One version of this code, viewable at http://www.hpjava.org/demo.html also has a novel parallel GUI implemented in HPJava.
The Euler equations are a family of conservation
equations, relating the time rates of change of various densities to
divergences of associated flow fields. In two dimensions
there are four densities--the ordinary matter density,
densities of the two components of momentum, and the energy density.
The Euler equations can be summarized as a conservation equation for
four-component vectors , and :