Numerical Simulation of Pollutant Distribution in Urban Environment

   The complex environmental situation in industrial regions requires the development of applied methods to assess the impact of industrial emissions on the environment.

   Purpose: Development of numerical simulation methods of pollutant distribution in urban environment.

   Methodology: Steady-state numerical simulation is performed in Ansys Fluent using the Species Transport model, which simulates mixing and transport of chemical substances by solving equations of concentration transport under the gradient diffusion hypothesis. The model is validated against classic 2D and 3D cases of substances mixing in a pipe.

   Research findings: Numerical simulation methods for the pollutant distribution in urban environment is developed and applied to nitrogen dioxide (NO₂) and sulphur dioxide (SO₂) emissions from chimneys of a cement plant in five wind directions. Practical capabilities of the developed methods are demonstrated, including clear visualization of the nature of the pollutant distribution from the point of emission, the concentration level of each substance in a selected area, and areas with exceeded maximum permissible concentrations. In this study, the distribution of substances resembles bands, which widen with increasing distance from emission sources. For the given mass fractions and emission volumes, maximum permissible concentrations for NO₂ and SO₂ exceed 7.9 and 8.9 times, respectively.

   Conclusions: The developed numerical simulation method of the pollutant distribution used in Ansys Fluent, are effective and informative for analysing the environmental situation in urban environment. However, for greater reliability, accurate, officially verified data on the qualitative and quantitative composition of emissions from industrial facilities is required, as well as the consideration of a greater number of factors influencing the concentration of harmful substances in the atmosphere.

1. Sysoeva, E.V., Gelmanova, M.O. Methods for Calculating the Pollutants Dispersion in Urban Atmosphere. Vestnik MGSU. 2022; 8: 1027–1045. DOI: 10.22227/1997-0935.2022.8.1027-1045 EDN: DZWYQY (In Russian)

2. Ravshanov, N., Juraboeva, O., Boborakhimov, B., Sharipov, Kh. Modeling the Pollutant Distribution in the Atmosphere, Accounting for Terrain and Meteorological Conditions. Problems of Computational and Applied Mathematics. 2025; 4(68): 38-46. DOI: 10.71310/pcam.4_68.2025.01 (In Russian)

3. Belostotsky, A.M., Akimov, P.A., Afanasyeva, I.N. Computational Fluid Dynamics in Construction Tasks. Moscow: ASV, 2017. 720 p. (In Russian)

4. Keshavarzian, E, Jin, R., Dong, K., Kwok, K.C.S., Zhang, Y., Zhao, M. Effect of Pollutant Source Location on Air Pollutant Dispersion Around a High-rise Building. Applied Mathematical Modelling. 2020; 81: 582–602. DOI: 10.1016/j.apm.2020.01.019. EDN: GSMKWI

5. Liu, X.P., Niu, J.L., Kwok, K.C.S., Wang, J.H., Li, B.Z. Investigation of Indoor Air Pollutant Dispersion and Cross-contamination Around a Typical High-rise Residential Building: Wind Tunnel Tests. Building and Environment. 2010; 45(8): 1769–1778. DOI: 10.1016/j.buildenv.2010.02.003

6. Amosov, P.V., Baklanov, A.A., Makarov, D.V., Masloboev, V.A. Numerical Simulation of Atmospheric Pollution in Random Selection of Discrete Dusting Sites and Interval Distribution of Dust Size. Vestnik of MSTU. 2022; 25: 61–73. DOI: 10.21443/1560-9278-2022-25-1-61-73 EDN: YBIHJK (In Russian)

7. Sandeep, Z., Preeti, Z. Dispersion Simulation to Assess Ambient Air Quality Impact Due to Carbon Industry. International Journal of Innovative Research in Technology. 2025; 12(3): 3774–3783.

8. Knyazev, D.K. Problems of Atmospheric Air Pollution in Inhabited Localities of the Volgograd Region by Emissions of Construction Industry Enterprises. Vestnik MGSU. 2017; 2(101): 193–200. DOI: 10.22227/1997-0935.2017.2.193-200 EDN: YGJDYX (In Russian)

9. Volodina, D.A., Talovskaya, A.V., Yazikov, E.G., Devyatova, A.Yu., Edelev, A.V. Assessment of Dust-Aerosol Pollution in the Area of Cement Plant Influence Based on the Snow Cover (Novosibirsk Region). Izvestiya Tomskogo politekhnicheskogo universiteta. 2022; 333(10): 69–85. DOI: 10.18799/24131830/2022/10/3704 EDN: FVOHDL (In Russian)

10. Volodina, D.A. Cement Plant as a Source of Dust-aerosol Pollution of the Atmosphere. In: Proc. 8^th All-Russ. Sci. Conf. ‘Young Creativity – A Step to a Successful Future’, Tomsk, 2015. Pp. 135–137. (In Russian)

11. Schefer, R.W., Dibbl, R.W. Simultaneous Measurements of Velocity and Density in a Turbulent Non-premixed Flame. AIAA Journal. 1985; 23(7): 1070–1078. doi: 10.2514/3.9039

12. Information and Technical Directory on Best Available Techniques "ITS 6-2024 Manufacture of cement" N 2231, 16.09.2024. Federal Agency on Technical Regulating and Metrology (Rosstandart). 2024. 298 p. (In Russian)

13. The plant in numbers. Available: https://sebcement.ru/proizvodstvo/zavod-v-cifrakh/ (accessed April 15, 2024) (In Russian)