NUMERICAL MODELING OF AIR POLLUTION NEAR THE HIGHWAY WITH PROTECTIVE BARRIERS

Abstract

Problem statement. The problem of predicting chemical pollution zones near the highway, where protective barriers are located, is considered. The protective barriers influence the aerodynamics of air flow and reduce the level of working areas chemical pollution near the highway. It is necessary to have mathematical models that allow such evaluation at the design stage in order to evaluate the effectiveness of protective barriers promptly. The purpose of the article. Development of a numerical multi-parameter model and computer program for evaluating the effectiveness of the protective barriers using near the highway to reduce the chemical contamination level of work areas. Methodology. A two-dimensional mass transfer equation is used for mathematical modeling of chemical hazardous substances spreading that are emitted from a car and spread near the highway. This simulation equation takes into account the wind direction, atmospheric diffusion, the intensity of chemically hazardous substance emission from the car, the emission source location, the car body and the location of protective barriers near the highway. The Navier − Stokes equation and the potential motion model both are used to solve the aerodynamics problem of determining the uneven air velocity field near the highway. An implicit splitting difference scheme is used to numerically integrate the vortex transfer equation. Two numerical schemes are used to numerically integrate the equation for the current function. An explicit difference scheme is used to numerically integrate the Laplace equation for the velocity potential. Based on the constructed numerical model the package of programs is developed. To solve numerically equation of pollutant transfer the finite difference schemes of splitting are used. Scientific novelty. To calculate the formation of chemical pollution areas for atmospheric air near the highway during emissions from vehicles numerical model is proposed. This model allow to estimate the protective barriers effectiveness for reducing air pollution in the working areas. Practical significance. Based on the developed model the code for quickly calculation of air pollution process both near the highway and in work areas protecting with barriers is created. Conclusions. The developed numerical model and the computer code implementing it allow to investigate the process of chemical hazardous substance spreading in the atmospheric air near the highway. The model allows to quickly determine the effectiveness of protective barriers using near the highway. The developed computer program can be implemented on low and medium power computers. The results of a computational experiment are presented.