2007 Volume 21 Issue 4 Pages 413-420
Large part of country in Japan is mountainous area. Many villages and large structures have the potential of damage by pyroclastic flow associated with volcano eruption. In order to prevent these disaster, the understandings on characteristic of pyroclastic flow is necessary. A hazard map can be made based on such knowledge. Also, the constructions of facilities preventing these disasters are possible. The flow mechanisms of pyroclastic flow are similar to the thermal flow on the inclined boundaries. The models and the numerical simulator on such flows are developed considering the three dimensional topography. Such a model was originally proposed by Fukushima and Kagiyama(1992). This numerical simulator can analyze the route of flow and lateral spreads of pyroclastic flow in addition to the velocity, the concentration of pyroclastic materials, the kinetic energy of turbulence. The simulator for the pyroclastic flow on the three dimensional topography can estimate the actual behaviors of these flows.