Detailed vibrational analysis of unbalanced morning glory spillways using coupled finite volume-finite element method

Abstract

In this research, the structural behavior of a morning glory spillway has been evaluated when there is an unbalanced construction in the spillway crest. The unbalanced construction is defined as the ratio of vertical unbalance in construction to the diameter of the spillway crest. The spillway structure has been modeled using finite element method and the reservoir fluid has been simulated using finite volume method. The behavior of morning glory spillways with unbalanced crests has been investigated in two scenarios: (a) the crest without any anti-vortex structure, and (b) the crest with anti-vortex structures. Both scenarios have been simulated using dynamic linear analysis method. In addition, in each scenario, three amounts of unbalanced constructions of 0.017, 0.035 and 0.052 have been considered. The analysis results have been compared with the structural response of a symmetric spillway without unbalanced construction. Based on the results, the most critical condition occurs during the water flow over the unbalanced spillway with no anti-vortex structure. On the other hand, the presence of anti-vortex piers causes asymmetric flow on the spillway crest and subsequently asymmetric flow pressure at one side of the piers.