GAP - A PIC-type fluid code

A description of a code for computing compressible flows is presented. In the code a number of particles which represent the fluid move on a fixed background grid. These particles serve as markers of fluid position and carriers of fluid properties. Attention is given to one-dimensional, one-material flow. Questions of heat conduction and viscosity are also briefly examined. The particle quantities considered include mass, position, velocity, internal energy, and volume. The grid quantities are density, pressure, specific internal energy, and force.