CHEMSIMUL: A chemical kinetics software package

CHEMSIMUL is a computer program system for simulation of chemical kinetics. It can be used for modeling complex reactions in many contexts. CHEMSIMUL contains a translator module and a module for solving the resulting coupled nonlinear ordinary differential equations, and it has a module for verifying the mass balance.

Pulse radiolysis and irradiation chemistry can be studied, as well as chemistry of high level waste radiation where decaying isotopes and their affiliations are considered. Transport phenomena and heterogeneous chemistry can be simulated by using “exchange equations”. Such equations admit simulation of general dynamic systems, with or without chemistry.

Other special features are Arrhenius calculation of reaction rates and tools for dealing with ionic strength. Standard chemistry notation is used in input files, and any number of reactions and reactants are accepted. Flexible graphical features with plot expressions are available. Besides quantities entering the differential equations it is also possible to work with “refreshable parameters”, which are defined by algebraic expressions.

A discussion of the mathematical implementation is given. The main computer platform is theWindows PC. CHEMSIMUL is coded with a modern GUI (graphical user interface). However, a classical command-driven version is available, too. The two versions use a common format of the basic input file and of the output report