An object-oriented serial implementation of a DSMC simulation package

Abstract

This paper reports a scalar implementation of a multi-dimensional direct simulation Monte Carlo (DSMC) package named “Generalized Rarefied gAs Simulation Package” (GRASP). This implementation adopts a concept of simulation engine and it utilizes many Object-Oriented Programming features and software engineering design patterns. As a result, this implementation successfully resolves the problem of program functionality and interface conflictions for multi-dimensional DSMC implementations. The package has an open architecture which benefits further development and code maintenance. To reduce engineering time for three-dimensional simulations, one effective implementation is to adopt a hybrid grid scheme with a flexible data structure, which can automatically treat cubic cells adjacent to object surfaces. This package can utilize traditional structured, unstructured or hybrid grids to model multi-dimensional complex geometries and simulate rarefied non-equilibrium gas flows. Benchmark test cases indicate that this implementation has satisfactory accuracy for complex rarefied gas flow simulations.