The problem-oriented library SOWFA for solving the applied tasks of wind energy

The article discusses the possibilities of the open source library SOWFA. The problem-oriented library, operating as part of the open source package OpenFOAM v.2.4.0, is intended for solving wind energy’s problems. In connection with the construction of new wind farms in the Russian Federation (Ulyanovsk region, The Republic of Adygea), the issues of designing and modeling the operation of wind farms and wind turbines are currently relevant. The article describes the structure of the SOWFA library and some of its classes. The study of the dynamics of self-organized turbulent structures and the assessment of their size are important from the point of view of maximizing the power generated by wind turbines, for analyzing the optimal location of wind turbines in wind farm. At the same time, it is necessary to study in detail the process of air’s ejection, the process of displacement of two media, in which one medium, being under pressure, affects the other and carries it in the required direction, in the area of the wind farm. The phenomenon of ejection plays a positive role and allows restoring the velocity’s deficit in the wake of the wind turbine, therefore, affects the wind capacity of wind farm. The phenomenon of ejection can be studied using the motion of solid particles. The article describes an example of adding a new KinematicCloud class to the ABLSolver solver, which describes a kinematic cloud of particles and an example of solving an applied wind energy problem for a model wind farm. The numerical domain for the model wind farm had the shape of a parallelepiped with given dimensions. The unstructured mesh contained 6 million cells. To determine the initial distribution of parameters, we used the neutral atmospheric boundary layer approximation, calculated using the Precursor method, implemented in the ABLSolver solver. The mathematical modeling of the flow parameters in the wind farm was done using the pisoFoamTurbine solver and the Actuator Line Model. In the course of calculation, for the case of a model wind farm with 12 wind turbines, the fields of averaged and pulsation values were obtained for velocity, pressure, subgrid scale viscosity, stress tensor, vorticity. The article compares the values of the dimensionless horizontal velocity in two different sections with the values obtained in the experiment. The calculations were performed using the resources of the high performance cluster of the UniCFD web-laboratory in ISP RAS.

library, model of turbulence, cloud of particles, wind turbine, wind farm, wind energy

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