An Eulerian approach for dynamic analysis of reservoir adjacent to concrete gravity dam

Abstract

The present paper deals with the finite element analysis of infinite reservoir adjacent to gravity dam. Two-dimensional eight-node isoparametric elements are used to discretize the domain. In order to reduce the degrees of freedom in the domain, the equation of motion for fluid motion is simulated by pressure-based Eulerian formulation. Different artificial boundary conditions are compared to obtain most suitable boundary condition. In this comparison of boundary conditions, it is noted that almost all the boundary conditions are frequency dependent. Some of the conditions are suitable for the exciting frequency less than the fundamental frequency of reservoir. However, the boundary condition proposed by Gogoi and Maity is suitable for all ranges of exciting frequencies. Further, the force vibration analysis is carried out with and without considering compressibility of water. The hydrodynamic pressure on dam is independent of exciting frequency when the compressibility of water in the reservoir is neglected. However, the effect of exciting frequency on the performances of reservoir is distinct for compressible fluid. Similarly, the magnitude and location of maximum hydrodynamic pressure change continuously, if the inclination of upstream face of dam is considered.