Ashaque Meah M., *Fazlul Karim
Abstract
The boundary-fitted curvilinear grids make the model grids fit to the coastline and the boundary conditions simple and more accurate. Also the method of lines (MOL) is a special finite difference technique which is more effective than the regular finite difference method in terms of accuracy, computational time and numerical stability. So a new numerical solution technique is presented to simulate the 2004 Indian ocean tsunami in a boundary-fitted curvilinear grid model where the vertically integrated shallow water equations are solved by using the method of lines (MOL). For this purpose the boundary-fitted grids are generated along the coastal and island boundaries and the other open boundaries of the model domain. To use the regular finite difference scheme to the spatial derivatives, a transformation is used so that the physical domain is transformed into a rectangular one. The method of lines is then applied to the transformed shallow water equations and the boundary conditions so that the transformed equations are converted into ordinary differential equations initial value problem. Finally the 4th order Runge-Kutta method is used to solve these ordinary differential equations and we use these results for tsunami computation associated with the Indian ocean tsunami 2004 along the west coast of Peninsular Malaysia and Thailand. All simulations show excellent agreement with the observed data.