Simulation of flow pattern around series of groynes with different orientations in meandering channels

Abstract

Abstract The mechanism of flow and turbulence around groynes in a meandering channel is very complex phenomena. To simulate the flow pattern around groynes in meanders a 3D numerical model was built with groynes of different inclinations by using ANSYS Fluent. The developed model was verified by the results of experimental study in meanders. Pressure, velocity, stream lines and turbulent kinetic energy for different groyne angles such as 15°, 30°, 45°, 90°, 120° and 150° were compared and analyzed to find the ideal angle configuration for different functions. Streamlines profiles were studied to understand more about the formation of scours and vortices around the groyne. The study of streamline profiles helped in the study of vortex and scours. The most dynamic variation in pressure and turbulent kinetic energy within the contours were found for groynes with 90° orientation. Large numbers of vortices between the groynes were observed for groynes with 15° and 90° orientation and these vortices were observed between the second and third groynes. For groynes in the meandering, the ideal angle for controlling the velocity was found out to be 45°, as it showed very small number of vortices in the groyne field. The results of the study showed that numerical modelling could be used efficiently for the study of flow and turbulence around groynes in meanders.