ملخص البحث :

Flood routing is an analytical method for determining a flood hydrograph in a river section by analyzing flood flow data from one or more upstream sections. Flood routing is used in hydrological analyses for major issues such as flood forecasting, flood protection, reservoir design, and spillway design. Two basic types of routing can be distinguished, which are reservoir routing and channel routing, the change in the hydrographic shape of the channel as it moves down the channel. A Lower Zab river in the north of the country was chosen as a case study. The Genetic expression programming (GEP) method was used in the modeling of the Lower Zab river event. The need to use a few hydrological parameters, such as inflow and outflow and time, was the most prominent positive feature of this application. The results showed the high suitability of the proposed predictive model for flood routing based on the simulation results and the possibility of using the GEP model as a suitable alternative to traditional methods such as the Muskingum model.

ملخص البحث :

In this study, four types of flood routing approaches were studied which give significantly varied results represented by the differences between computed and observed flows and also differ considerably on the friction coefficient and bed slope of the channels. First two approaches use a hydraulic solution to solve the equations of unsteady flow, while the third approach uses the hydrological solution, and the fourth algorithm solves Muskingum approach with seven parameters. All these approaches were run with the same input parameters, the results were compared and tested with four Error Measurement Indices, Sum of Squared Deviations, Error of Peak Discharge, Variance Index, and agreement index. Diyala River was selected for this application. Dynamic wave method gave accurate results, followed by the characteristic method, and then the linear Muskingum-Cunge method, but Symbiotic Organisms Search Algorithm not gave any senses due to change in roughness or bed slope and gave very identical values with recorded outflow in all conditions, which means that the hydraulic solution is better compared to the hydrological solution. The results also showed that the difference between the calculated and observed flows diminished with a decrease in the coefficient of friction and an increase in the bed slope channel.

ملخص البحث :

Flood routing in natural channels is essential to predict the location and the physical properties of the flood waves, whichis very important for the design of hydraulic structures and flood control processes and strategies. For example, the floodrouting gives accurate information on flood peak and the period of water level rise.