Performance of solid material diverter subject to impact collision with respect to angle variation

Abstract

Sustainable Hydrokinetic Renewal Energy Power Generation System (SHRE) is an energy harvesting system that operates in the river of Sarawak and subjected to impact of floating debris. In order to resist the impacts from floating debris, the Solid Material Diverter (SOLMAD) is proposed for the protection of SHRE system. Floating debris in the river, normally timber logs, could damage the SOLMAD and misalign the turbine orientation, which in return could reduce the lifespan and efficiency of the hydrokinetic turbine to harness energy. This research aims to model SOLMAD of various angles that are subjected to impact loading induced by floating debris. Five angle variations, namely 15°, 30°, 45°, 60°, and 75° were taken into consideration for analysis and design of the SOLMAD. The size of timber logs, river profile, and flow velocity were obtained from site sampling data collection at the Balleh River, Sarawak. The mass from the recorded sampling of floating debris and velocity of the river were then converted into equivalent impact forces on the SOLMAD structure using the Work-Energy method. Scaled down models were investigated experimentally in the laboratory to investigate their stability and validate the theoretical impact forces calculated using the Work-Energy method. A total of five models were developed with 3-dimensional line elements using the STAAD.Pro software. The models were analysed under the most critical load cases using the calculated equivalent impact forces to obtain the internal forces and displacements. The models were then designed with optimised steel section using Eurocode 3. The study showed that structural orientation of 15° and 30° performed better in terms of stability and float ability on the water compared to the other angle orientations. From the structural design standpoint, by using Eurocode 3, angle section of 100 mm x 100 mm x 12 mm and 150 mm x 150 mm x 12 mm were adopted as the most optimum sections to design the SOLMAD. Based on the overall performance of structural stability in water and structure self-weight, the selection of 30° model was proposed as the SOLMAD structure.