A systematic computational study of debris cluster impact on the performance of utility-scale marine hydrokinetic turbines under mobile bed conditions*

Tidal and riverine flows offer reliable sources for energy production. Still, the installation and operation of marine hydrokinetic (MHK) turbines might alter sediment transport processes, and interactions with debris could negatively affect flow as well as turbine performance. Therefore, assessing the potential impact of debris accumulation on turbine performance and sediment transport is crucial. This study couples large-eddy simulations with a bed morphodynamics model to study the performance of a utility-scale horizontal-axis MHK turbine with various debris clusters over the upstream face of the turbine tower. The geometry of turbine components, waterway, sand waves, and woody debris are modeled directly using the immersed boundary method. Our findings demonstrate the effect of debris accumulation and sediment dynamics on the wake recovery and turbine performance.