A mass conservative and water storage consistent variable parameter Muskingum-Cunge approach

• DOI: 10.5194/hess-11-1645-2007
• Publication Date: 2010-04-29T14:52:17Z
• Authors: E. Todini
• Keywords: Constant (computer programming)

Abstract. The variable parameter Muskingum-Cunge (MC) flood routing approach, together with several variants proposed in the literature, does not fully preserve mass balance, particularly when dealing very mild slopes (<10−3). This paper revisits derivation of MC and demonstrates (i) that loss balance is caused by use time variant parameters which violate implicit assumption embedded original Muskingum scheme, implies constant at same (ii) estimated means Cunge approach two basic equations formulation. also derives modifications needed to allow and, time, comply formulation terms water storage. properties algorithm have been assessed varying cross section, slope, roughness, space integration steps. results all tests show new always conservative. Finally, it shown closely approaches full de Saint Venant equation solution, both levels discharge, parabolic approximation holds.