Coastal forests have received considerable attention in recent years as an ecodisaster risk reduction (Eco-DRR) management system for water-related disasters, especially tsunami. The effects of natural trees on the inundation flow motion should be sufficiently investigated for better disaster mitigation planning. We have challenged to develop reasonable and accurate modeling of trees drag effects based on the 3D CFD techniques.
The sediment transports have caused the damage and the delay of restoration in the 2011 Tohoku tsunami. The tsunami simulations have to consider the effects of the involved sediment grain, although the 3D simulation based-approach needs enormous computational resources. We, therefore, have focused on the 'macroscopic viscosity' as the representative parameter of the sediment-water mixed fluid modeling. The macroscopic viscosity, measured from the fluid-structure interaction simulations, would contribute to describing the motion of inundation flow involving sediments.
R. NOMURA, K. TERADA, S. TAKASE, S. MORIGUCHI, "A Method of Numerical Viscosity Measurement for Solid-Liquid Mixture", Multiscale Modeling of Heterogeneous Structures, Lecture Notes in Applied and Computational Mechanics, Vol. 86, pp.347-364, 2018. DOI 10.1007/978-3-319-65463-8, Hardcover ISBN 978-3-319-65462-1