NUMERICAL SIMULATION OF TSUNAMIS GENERATED BY ICEBERG CALVING

Abstract

Calving icebergs falling into water can generate large tsunamis, so-called iceberg-tsunamis. This phenomenon poses a threat for the fishing and shipping industries and coastal communities. Examples in Greenland include a 50 m amplitude wave recorded during an iceberg calving event at the Eqip Sermia glacier in 2014 and a tsunami generated by a capsizing iceberg in 1995 damaging a harbour. This work aims to numerically model the generation and propagation of such iceberg-tsunamis with the open source code Foam-extend 4.0. The original multiphase flow solver relying on the Immersed Boundary Method in this code has been modified to handle moving immersed boundaries, and it was then coupled with a motion solver to determine the iceberg motion. This method is validated with an own large-scale iceberg-tsunami test conducted in a 50 m × 50 m basin. The results show that the numerical iceberg motion and tsunamis generally agree with the laboratory observations. Further, the presented model can capture the laboratory wave heights and decay well. Future work will focus on simulating additional iceberg calving scenarios as well as modelling turbulence.