Effect of Material Behaviour on Flow Uniformity over Different Spillway Weir Profiles

Abstract

The spillway weir system finds an important application to achieve uniform flow in the open canal stream passages, for irrigation and in many industrial processes, majorly including cooling of reactor components with liquid sodium in prototype fast breeder reactors, process plants, and power industries. The optimal design of weir profile and the velocity of flow over the weir are the critical factors that need to be optimized to minimize flow separation in order to avoid entrainment of gas in flowing liquid, and also, the nonuniform cooling resulted in uneven temperature distributions in many thermohydraulic structures. In this research, the spillway weir profile made from SS-316, SS-304, concrete, and teak wood is compared for optimization of flow uniformity by means of hydraulic experiments conducted on the water-air model and also to investigate the behavior of flow past over the rectangular weir of three different radii 6 mm, 6.47 mm, and 7 mm, respectively, and the minimum of 1.2% flow separation was observed with 6.74 mm profile, and also, the computational fluid dynamics (CFD) based numerical simulation was performed in the fluid domain to validate the experimental data to attain the flow uniformity when flow past over the spillway weir profile and the results are highlighted. The experimental results on air entrapment, water film thickness, and velocity of water over the weir profile on the perspective of uniformity of flow are also discussed in detail.