A tool to improve the execution time of air quality models

High dimensional model representation (HDMR) techniques are tools to improve mathematical modeling of physical systems. One of the main HDMR applications is the development and use of a fully equivalent operational model (FEOM) in the modeling of a physical system described by means of a set of ordinary differential equations. The accuracy of a system's output approximation obtained by using HDMR expansions is comparable with other approximation methods while the computational effort is much lower.We use FEOM to solve the initial-value problem for the stiff systems of ordinary differential equations which describe the chemical reactions' mechanisms used in the three-dimensional model of diffusion/advection of air pollutants. With the use of FEOM we achieved noticeable computational savings.We apply the developed FEOM to two different schemes of chemical reactions and give some general recommendations for the efficient FEOM implementation based on the obtained experience.