Debris flow is an extremely dangerous natural hazard, which routinely destroys wind farms in mountainous terrains. To intercept this hazardous phenomenon, rigid barriers are commonly installed in mountainous regions to mitigate the hazard of debris flow. In order to study the impact of debris flow on a rigid barrier, this paper presents a coupled Discrete Element Method and Computational Fluid Dynamics approach. This approach compares the interactions between single- and two-phase flows and a rigid barrier. The results show that the single-phase flow exhibits a predominant pile-up mechanism, while the two-phase flow in this study show a distinct run-up mechanism. Compared to the single-phase flow, due to the drag and buoyancy effect of water, the number of contacts inside particles is reduced, and less energy is dissipated. Correspondingly, the run-up height and maximum impact force of granular system increases by 426% and 488%, respectively.
Key words
onshore wind farm /
computer simulation /
fluid structure interaction /
debris flow /
rigid barrier /
impact
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