Author(s): J. Ikhsan; S. Hardjosuwarno; A. P Rahardjo
Linked Author(s): Jazaul Ikhsan
Keywords: Early warning; Debris flow; Numerical model; Finite difference; Volcanic are
Abstract: The debris flow events in volcanic area often cause disaster in surrounding rivers, so they have increased loss of lives and infrastructures. In order to reduce the loss of lives due to the debris flows, it is important to develop an early warning system. To predict the threatened area along the river by debris flow could be forecasted using a numerical model. Therefore, it is required to develop a numerical model of debris flow as a tool for forecasting the area. The objective of the research is to create a numerical model for a tool in early warning system. The model of debris flow was developed based on the two equations. The equations were water flow and sediment flow equations. Both of these equations were discreet using finite difference method. To check the performance of the numerical model, two cases of debris flow are carried in Putih River, Sleman District, Yogyakarta Province, Indonesia. The first case is without sabo structure and second case was using sabo structures. The simulations were performed and then, the simulation result was compared with the disaster prone area from the government. The simulation results showed that the numerical model was capable to simulate the affected flood areas. Sabo structure was also effective to reduce the debris flow.