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The results of an experimental study of the interfacial tension and surface wettability in the nanosuspension/oil/rock system are given. The effect of the concentration and size of silicon oxide nanoparticles on the coefficient of interfacial tension and the contact angle of wetting has been systematically studied for the first time. A wide range of weight concentrations of nanoparticles (from 0 to 1 wt %) and their average sizes (from 5 to 50 nm) are considered. It is established that the use of nanosuspensions makes it possible to radically change the wettability of rocks with respect to oil. In this case, this effect depends substantially on the concentration and size of nanoparticles.

This paper presents the results of working out the methodology for conducting experimental studies of the flow around the objects modeling the urban environmental conditions. The experiments were conducted in the wind tunnel of the Siberian Federal University. Two objects of different heights imitating buildings were considered the models. Special attention was paid to the study of the flow pattern at the tandem arrangement of model buildings. Visualizing the flow, the low-velocity and high-velocity zones, as well as recirculation areas were identified. At that, these zones had their peculiarities in terms of the direction of flow twisting behind each object. The study allowed revealing that the vortices separating from the edges of the studied objects play a special role in the flow formation.

The paper presents a comprehensive analysis of the wind flow interaction with a high-rise building, considering various types of streamlined flow acceleration, as well as an assessment of the aerodynamic shadow behind the building, and areas with increased wind speeds. The authors analyze risks caused by these zones, as well as suggest measures to minimize them.

The article considers the influence of the relief, river, and urban development on the formation of vortex structures in the atmosphere and the spread of pollutants in the city of Krasnoyarsk in winter. The weak influence of urban development on the appearance of large vortex structures over the river is shown. However, in the ground layer, it significantly changes the flow pattern and determines the character of the distribution of pollutants.

In this paper, a comprehensive analysis of the interaction of the urban environment elements with the natural environment components is carried out. The assessment of the complex impact of meteorological parameters on the human body is analyzed based on data obtained from monitoring stations. The readings of monitoring stations concerning both wind speed and directions are found to significantly deviate in different parts of the city due to urban development. A numerical study of the neighborhood with the monitoring station also shows a very complex mechanism for determining the pollution intensity of the area and the relevance of the data obtained, especially concerning pollutants.

The paper presents the numerical simulation of the distribution of pollutants in winter in the atmosphere of Krasnoyarsk city. The source of the pollution is the suburban areas of the city of Krasnoyarsk, in which coal stove heating prevails. A micro-scale mathematical model based on the solution of the system of non-stationary Reynolds equations is used for modeling. The influence of various factors, such as elements of terrain and urban development, on the distribution of pollutants is studied in the paper.

The paper presents the results of systematic experimental studies of interfacial tension (IFT) and oil wettability of three different types of rock (dolomite, metabasalt, and sandstone) in nanosuspensions. Nanoparticles of silicon and aluminum oxides were used at the concentration ranged from 0.01 to 1 wt%. It is shown that with increasing NP concentration, the contact angle of an oil droplet resting on a rock in a nanosuspension increases quite essentially (from 33 to 153°). The nanoparticle size and compositional effects on interfacial tension coefficient and contact angle (CA) within a wide range of particle concentrations were systematically studied for the first time. The contact angle oil/dolomite/nanofluid increased from 92 to 151° with decrease in the SiO2 nanoparticle size 50 nm to 5 nm. With an increase in the NP size from 5 to 50 nm, there was a decrease in interfacial tension of about 30%. The first-ever experiments were conducted to study the influence of nanoparticles in water on the oil wettability of various types of hydrophilic and hydrophobic rocks. It is shown that the wettability characteristics of various types of rocks can be controlled by adding minor amounts of nanoparticles of different sizes and compositions to influence the parameters that play a key role in the problems related to oil recovery enhancement during reservoir flooding.

The paper reveals the capabilities of SigmaFlow CFD code to predict wind conditions in terms of pedestrian comfort as illustrated by a model problem. The proposed numerical model was verified by comparing with experimental data. A group of buildings consisting of low-rise buildings and a high-rise building was considered. A comparative analysis of five computational variants with different grid saturation was performed. The results of mathematical modeling allow observing the vortex flow structure that is generated when streamlining buildings.

This article presents the results of numerical modeling of wind flows around a microdistrict. The distribution of suspended solids of 50 and 100 microns in urban environments is considered. The characteristic of urban development in terms of a comfortable stay of people is given.

There are the computerised simulation results of the airflow around Krasnoyarsk residential areas (“Tikhiye Zori” and “Beliye Rosi”) and the impact assessment of these estates on particular areas of the city.

The article analyzes the environmental situation in the city of Krasnoyarsk based on data of the Ministry of Natural Resources and the Ministry of Ecology and Environmental Management of the Krasnoyarsk Territory. The influence of the non-freezing Yenisei River on the movement of air masses over the city is considered based on numerical simulation. The obtained results demonstrate the ability to quickly simulate the wind pattern of the city, taking into account the heterogeneous nature of the terrain, heat transfer, wind load, and the influence of the river.