Numerical modelling of pollution transport in Tom River

This work constructs a mathematical model and a computational method to getмextensive data about the structure of a river stream essential for predicting the behaviorиof a river. The model proposed is based on depth-averaged Reynoldsaveraged Navier–Stokes equations. The solver is based on the finite volume method on a staggered structured grid and a high-order Monotonic Upwind Scheme for Conservation Laws for convective fluxes. The solution is obtained with a Semi-Implicit Method for Pressure Linked Equations iterative algorithm based on coupled correction of the depth and velocity fields at each time step. The principal innovation of the algorithm proposed is accounting for the variability of the water depth in the source term in the momentum equations. The results show that the approach proposed accurately predicts the flow field and concentration field and demonstrate the significant role of the flow turbulence in transport of pollution in the river stream

Mathematical modeling of a river stream based on a shallow water approach

Flood control problems as well as problems connected with wastewater discharge into rivers are issues of current importance. Depth averaged shallow water equations are used to model flows where water depth is much less than the horizontal dimension of the computational area and the free surface greatly influences the flow

Large eddy simulation of turbulent flow and of pollutant transport in a street canyon

The work presents a non-steady three-dimensional eddy resolving model intended for the simulation of non-isothermal turbulent separation flows in street canyons. For a subgrid-scale turbulence parameterization, the Smagorinsky gradient model is used. The calculation results demonstrate the effects of pollutant source location, street canyon size, basic stream rate and wall temperature difference on air pollution in the canyon. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Application of a Weather Research and Forecasting model to study the urban heat island in Tomsk

The results of application of a Weather Research and Forecasting model (version 4.2) to study the heat island phenomenon in the city of Tomsk are considered. The results of numerical calculations were compared with measurements obtained using the instruments of Joint Use Center (JUC) Atmosphere and Tomsk Bogashevo Airport. On some days, the temperature difference between the city and the suburbs was shown to reach 1-3 °C

Using weather prediction data for simulation of mesoscale atmospheric processes

The paper presents an approach to specify initial and boundary conditions from the output data of global model SLAV for mesoscale modelling of atmospheric processes in areas not covered by meteorological observations. From the data and the model equations for a homogeneous atmospheric boundary layer the meteorological and turbulent characteristics of the atmospheric boundary layer are calculated. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Global meteorological forecast data and instrumental measurement application for simulation of mesoscale atmospheric boundary layer processes

The accuracy of the results of numerical modeling of local atmospheric processes, in particular those in the ground layer, to a great extend depends on the input data characterizing the initial state of meteorological parameters within the area of research or their variation at the boundary. The paper considers a mesoscale model of atmospheric ground layer where medium-range weather prediction data calculated with the help of the global SL-AV model of the Hydrometcenter of the RF are applied as the initial and boundary conditions. Besides, the results of measurements carried out in the Institute of Monitoring of Climatic and Ecological Systems, SB RAS (IMCES) with the help of meteorological stations and temperature profiler are used for quality improvement

Influence of the pollution source location on the concentration of the impurity in street canyon

The work is devoted to the study of the flow structure and the nature of the impurities distribution in a street canyon, depending on the location of a constant intensity pollution source. The paper considers three cases when the source of the impurity is located: in the center at the bottom of the street canyon, at the bottom under leeward wall and at the bottom under windward wall

Numerical modelling of pollutant propagation in Lake Baikal during the spring thermal bar

In this paper, the phenomenon of the thermal bar in Lake Baikal and the propagation of pollutants from the Selenga River are studied with a nonhydrostatic mathematical model. An unsteady flow is simulated by solving numerically a system of thermal convection equations in the Boussinesq approximation using second-order implicit difference schemes in both space and time. To calculate the velocity and pressure fields in the model, an original procedure for buoyant flows, SIMPLED, which is a modification of the well-known Patankar and Spalding's SIMPLE algorithm, has been developed. The simulation results have shown that the thermal bar plays a key role in propagation of pollution in the area of Selenga River inflow into Lake Baikal