Effects of baffle shape on the performance of debris-resisting baffles: A numerical investigation

Abstract

Due to climate change brought on by global warming, severe rainstorms and landslides produced by debris flows have become more common in Korea and elsewhere recently. The closed-type and open-type barriers are the two major types of debris-resisting barriers. When compared to closed-type barriers, open-type barriers have the advantages of being more environmentally friendly and not harming the surrounding landscape. In this study, the performance analysis of the open-type baffles with four different shapes (arched, cube, circular, triangular) was performed under two flow conditions (large and small Froude numbers) and two viscosity conditions (high and low viscosities). The simulations were performed with DualSPHysics based on the Smoothed particle hydrodynamics (SPH) method. The velocity reduction ratio was evaluated by comparing the velocity before and after the collision with the baffle, and the performance evaluation was conducted based on it. Due to its concave design, the newly suggested arch shape has the advantage of trapping debris flows. As a result, the arch-type baffle performed the best, while the triangle baffle performed the worst under dilute debris flow conditions. On the other hand, there was little variation in performance amongst baffle shapes under viscous conditions.