FORECASTING DUST AIR POLLUTION IN A VENTILATED VOLUME WITH COMPLEX GEOMETRY

Problem statement. At the stage of pre-launch preparation, it is necessary to fulfill very strict conditions regarding the environmental conditions inside the main fairing, where the satellite is located. Namely, it is very important to predict the concentration of dust inside the main fairing and near the surfaces of the satellite during forced ventilation. Therefore, an important task arises − predicting the level of dust pollution of the air inside the fairing and determining the degree of pollution of especially “sensitive” surfaces. To adequately solve this problem, it is necessary to have scientifically based mathematical models. The purpose of the article. Development of a fast-calculating numerical model for predicting dust contamination of the fairing volume at the pre-launch preparation stage. Methodology. A numerical model has been developed to predict the dust regime of the main fairing of the launch vehicle. Modeling equations: dust mass transfer equation (takes into account dust transport due to convection, diffusion and gravitational deposition), equation for the velocity potential (determination of the air flow velocity field when flowing around the satellite in the main fairing), empirical dependencies that help determine the intensity of dust deposition on the satellite surface. Scientific novelty. A multifactorial numerical model has been developed for the analysis of dust contamination of the fairing during its forced ventilation at the stage of thermostating. The model makes it possible to solve the problem of aerodynamics and mass transfer in areas with a complex geometric shape. Finite-difference schemes are used for the numerical integration of the modeling equations. Practical significance. The developed numerical model makes it possible to quickly determine the level of dust contamination both in the fairing itself and in the areas of particularly “sensitive” surfaces of the satellite. Conclusions. Based on the proposed numerical model, a computer code has been developed. The results of computational experiments to estimate the dust concentration field inside the main fairing of a launch vehicle are presented.