3D SIMULATION OF FLOW AROUND DIFFERENT TYPES OF GROYNE USING ANSYS FLUENT

Abstract

The objective of this project is to study flow pattern around a single spur-dike or groyne with free surface flow using a numerical model prepared in a software known as ANSYS FLUENT 16.0. Model is prepared to investigate the 3D turbulent flow field around a single straight (SD), two repelling type groyne 45o and 60o (RG-45 and RG60) and two different T-shape groynes: TF (groyne with full wing length) and TH (groyne with half wing length) under smooth flat-bed condition. The study shows intense effects on turbulent and mean flow characteristics of different shapes of the groyne, especially for the near-bed region. Amplification of near-bed velocity is due to contraction of the channel cross-section and as well as due to local effects of the groyne structure is higher in the case of SD and repelling groyne (RG-45 and RG-60) than that of T-shape groynes. Horseshoe vortex variation at the base of spur is more compact & strong rotational momentum in the case of RG-45 then others. Observed decreasing order of this compactness & rotational momentum is RG-45; RG-60; SD-90; TH & at last TF. Increased wing length in the case of full wing length T-shape groyne (TF) effects the flow structure at the upstream mini embayment. Dominantly horizontal circulation flow occurs in place of vertical, due to which horseshoe vortex disappears. So we can say that increased wing segment act as a scour countermeasure.