Title: Analytical and Numerical Solutions to Level Pool Routing Equations for Simplified Shapes of Inflow Hydrographs
Journal: Iranian Journal of Science and Technology, Transactions of Civil Engineering
Year: 2022
Volume number: 46
Issue: August
Pages: 3147–3161
DOI: 10.1007/s40996-021-00757-x
Abstract: Reservoir routing is a technique to predict an outflow hydrograph expected from a dam outlet due to a specific inflow hydrograph. This study develops a series of analytical solutions for determining outflow hydrographs with detailed calculation procedures when a triangular, abrupt wave, flood pulse, broad peak, and double-peak inflow hydrographs occur upstream of a typical reservoir with an orifice outlet. The proposed analytical solutions are used as benchmarks to evaluate 16 schemes of a conventional numerical method so-called Runge-Kutta method, and the main equations for sensitivity analyses. The results indicate that the best scheme among those 16 Runge-Kutta schemes is the Kutta-Merson scheme for all types of inflow hydrographs except the double-peak inflow hydrograph in which the Cash-Karp method outperforms others, and the peak of the inflow hydrograph and the water area supplied by the reservoir are the two most sensitive parameters influencing outflow hydrographs results.
Keywords: Reservoir routing, analytical solution, sensitivity analysis, Runge-Kutta scheme, outflow hydrograph