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An alluvial river system mostly comprises of series of turns, loops or bends in its course. This study presents the experimental investigation of the turbulence structure at the centre of a sinuous sand bed channel with rigid banks. To examine the turbulent flow, distribution of instantaneous velocities, Reynolds stresses and bursting events were analysed at the centre of the bend. In this regard, Reynolds shear stresses (RSS) distribution exhibits the existence of reversal of flow in a bend. Close to the channel bed, RSS presents a triangular positive distribution as has been observed in straight flow, and away from the bed, it attains negative value. Furthermore, an assessment of bursting events shows the ejection and sweep events prevail near the bed whereas away from the bed outward and inward events are prominent. In addition to this, analyses of these events reveal that contributions from sweep events (inrush of fluid moving towards the bed) are maximum nearer to the channel bed. Turbulence scale such as Taylor micro scale and Eulerian scale were also determined to measure the eddy size and its turn over time. The Eulerian length scale and Eulerian time scale are observed greater at the centre of the flow depth. [ABSTRACT FROM AUTHOR]