Abstract

Abstract. The rainfall–runoff conceptual model as a cascade of submerged linear reservoirs with particular outflows depending on storages of adjoining reservoirs is developed. The model output contains different exponential functions with roots of Chebyshev polynomials of the first kind as exponents. The model is applied to instantaneous unit hydrograph (IUH) and recession curve problems and compared with the analogous results of the Nash cascade. A case study is performed on a basis of 46 recession periods. Obtained results show the usefulness of the model as an alternative concept to the Nash cascade.

Highlights

  • The significance of the rainfall–runoff relation conceptual model introduced by Nash as a linear cascade of reservoirs (Nash, 1957) and developed later as parallel cascades (Wittenberg, 1975; Oben-Nyarko, 1976) known nowadays as the Diskin model (Diskin et al, 1978; Diskin, 1980) cannot be overestimated

  • instantaneous unit hydrograph (IUH) and recession curves yielded by SC2 were compared with analogous Nash model results

  • 0.90 (c) of equations describing water flow throughout the cascade, the value of the storage coefficient k for the last reservoir in the chain is doubled in relation to the previous reservoirs, which allows determination of the eigenvalues of the equations set as roots of successive Chebyshev polynomials of the first kind

Read more

Summary

Introduction

The significance of the rainfall–runoff relation conceptual model introduced by Nash as a linear cascade of reservoirs (Nash, 1957) and developed later as parallel cascades (Wittenberg, 1975; Oben-Nyarko, 1976) known nowadays as the Diskin model (Diskin et al, 1978; Diskin, 1980) cannot be overestimated. Bárdossy (2007) noticed the great uncertainty of the identified cascade parameters and related difficulties in the determination of the optimum parameters set for a particular catchment. These problems, together considered with the high diversity of real hydrographs shapes in-

Theoretical considerations
Physical interpretation of the SC2 model assumptions
Solution to the IUH problem
Solution to recession curves
Comparison of SC2 and Nash model hydrographs
Case study – recession curves for real catchments
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call