A simple numerical algorithm and software for solution of nucleation, surface growth, and coagulation problems

In this article, a simple numerical method to solve the general dynamic equation (GDE) has been described and the software made available. The model solution described is suitable for problems involving gas-to-particle conversion due to supersaturation, coagulation, and surface growth of particles via evaporation/condensation of monomers. The model is based on simplifying the sectional approach to discretizing the particle size distribution with a nodal form. The GDE developed here is an extension of the coagulation equation solution method developed by Kari Lehtinen, wherein particles exist only at nodes, as opposed to continuous bins in the sectional method. The results have been tested by comparison where simple analytical solutions are available, and are shown to be in excellent agreement. By example we apply the model to the formation and growth of Aluminum particles. The important features of the model are that it is simple to comprehend; the software, which we call nodal GDE solver (NGDE), is relatively compact; and the code is well documented internally, so that users may apply it to their specific needs or make modifications as required. The C files mentioned in this article are available online at http://taylorandfrancis.metapress.com/openurl.asp?genre=journal&issn=0278-6826. To access this file, click on the link for this issue, then select this article. In order to access the full article online, you must either have an institutional subscription or a member subscription accessed through www.aaar.org.