| Flood planning, forecasting, and emergency management can be greatly enhanced through the use of models which have the ability to estimate the timing and location of flooding. Until recently, flood modeling has been dominated by one-dimensional models since these models are relatively simple and computationally quick. However, these models do not represent any of the complex physical processes present in floodplains and urban environments, and are therefore being discouraged by the National Research Council for use in floodplain inundation studies. Two-dimensional models based on the complete shallow water equations have a superior ability to resolve flow velocity and direction when compared to one-dimensional models. However, the limitation of using two-dimensional models for flood planning, forecasting, and emergency management is the increased computation cost. This dissertation presents the development and validation of a two-dimensional model based on the complete shallow water equations. For computational stability, the advective terms are resolved using an upwind differencing scheme, with the scale and velocity vectors located on a staggered grid. The model has been validated with laboratory experiments and has shown the ability to accurately estimate both velocities and depths. In addition, simulation results compared well to high water mark data collected from the Taum Sauk dam failure.;To decrease the computational cost, the two-dimensional model has been developed to take advantage of now prevalent multicore computers through Java multithreading to provide parallel computing on desktop computers. This desktop parallel computing capability coupled with an efficient domain tracking algorithm is shown to decrease computation time by as much as 200 times. Aside from an ability to provide more real-time flood forecasting, this reduction in computation time makes the incorporation of risk and uncertainty/ensemble forecasting more feasible for flood inundation modeling.;However, as the scale of the simulation is increased (urban to region) and with the increasing availability and use of high resolution data, computation times will increase. Therefore, understanding the relationship between grid resolution and model simulation results becomes very important. Unlike previous grid resolution studies, a grid resolution study is conducted herein which includes not only grid impacts to inundated area and velocities, but also considers socio-economic impacts, an important consideration in floodplain planning and management. The study results show that depths and velocities show greater sensitivity to grid resolution than inundated area and socio-economic impact assessment. |
