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An Eulerian PPM & PIC Code for Cosmological Hydrodynamics

A. Sornborger·B. Fryxell·K. Olson·P. MacNeice
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Abstract

We present a method for integrating the cosmological hydrodynamical equations including a collisionless dark matter component. For modelling the baryonic matter component, we use the Piecewise Parabolic Method (PPM) which is a high-accuracy shock capturing technique. The dark matter component is modeled using gravitationally interacting particles whose evolution is determined using standard particle-in-cell techniques. We discuss details of the inclusion of gravity and expansion in the PPM code and give results of a number of tests of the code. This code has been developed for a massively parallel, SIMD supercomputer: the MasPar MP-2 parallel processor. We present details of the techniques we have used to implement the code for this architecture and discuss performance of the code on the MP-2. The code processes $5.0 \times 10^4$ grid zones per second and requires 53 seconds of machine time for a single timestep in a $128^3$ simulation.

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A. Sornborger, B. Fryxell, K. Olson, P. MacNeice. 1996-08-05. An Eulerian PPM & PIC Code for Cosmological Hydrodynamics. https://arxiv.org/abs/astro-ph/9608019

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