A moving domain formulation for modeling two dimensional open channel transient flows

摘要

Numerically solving the two dimensional open channel flow equations over large spatial domains coupled with long time periods using an explicit finite difference scheme is constrained by the required computational time. To overcome this limitation, in this paper the effect of using a moving boundary algorithm on both the accuracy of the transient solution and on the associated computational savings is investigated. While all the reported studies that relate to solving the two dimensional shallow water open channel flows have used fixed domain boundaries, this work differs from them in that the location of the domain boundaries is a function of the time period. The theory underlying the Eulerian school of thought is used for identifying the coordinates of the domain boundaries. The results indicate that for simulations in which the transient solution is required, the present approach can accelerate the solution with out affecting its accuracy.