Papers by Keyword: Hydraulic Jump

Abstract: In stilling basins there is a change in flow regime from supercritical to subcritical flow; this transition is called a hydraulic jump. To control and stabilize the position of the jump, it is necessary to place a sill across the flow. A bibliographical analysis showed that when the controlled hydraulic jump is entirely formed upstream of the stilling basin, the sill has no effect on the configuration of the jump. However, when the jump length stretches beyond the sill position, this results in jump compactness and leads to several configurations of the latter, until it completely disappears. The main objective of this study is to determine the effect of the hydraulic jump compactness on the main jump features in a trapezoidal horizontal channel. Dimensionless empirical relationships depending on the jump compactness are obtained. Through this study, we aim to show the advantages of the jump compactness on the channel dimension. Indeed, the hydraulic jump is led to its most reduced form, before disappearing, in terms of tail water depth and jump length. Thus, the obtained results are useful for dimensioning the stilling basin.

Abstract: The paper proposes to realize a simulative analysis following the theoretical notions regarding the hydraulic jump, at flow of fluids through open channels, when open a plane penstock, which is located in a trapezoidal channel. A penstock is formed from a plan panel with upright movement in supports, with the possibility of adjustment a fluid flow by means of a handling device.

Abstract: This paper illustrates how Space-time Conservation Element and Solution Element (CE/SE) method which is developed for compressible flow can be used to solve the Saint-Venant equations numerically. The sharp shock-capturing capability of the scheme is demonstrated through the simulation of hydraulic jump phenomenon in prismatic open-channels. Two channel cross-section geometries are considered, viz rectangular and triangular cross sections. The code developed for the present study is validated by solving the benchmark problem of dam-break flow. The numerical solution of the Saint-Venant equations for the rectangular channel is found to be in good agreement with the experimental data available in the literature. The effect of channel wall slope on hydraulic jump in triangular channel is also discussed in this paper.

Abstract: This paper was concerned with a vertical two-dimensional (2D) flow model with free surface. The water governing equations were discretized with finite difference method. The function of volume method was employed to track the moving free surface. The model was used to predict the characteristics of hydraulic jump flow in a 2D vertical plane. The surface profile and time averaged velocity were calculated, which shows the proposed model can be capable of capturing sharp water and gas interface configuration as time changes.

Abstract: To protect downstream of hydraulic structures against erosion and degradation, must dipress water energy. one of the most comon methods to achive this purpose is constructing the stilling basin at the downstream of such structures. In stilling basin, the water energy dissipated by taking place of hydraulic jump. When a hydraulic jump occurs, the hydrodynamic and hydrostatic forces effect on the stilling basin floor slab. These forces include the force due to water weight and the up lift force affected the slab below which these forces are classified in hydrostatic. also the other force is hydrodynamic force due to pressure fluctions below the hydraulic jump. To keep the stilling basin stabillity from liffting up and destruction must the resistant forces be equal to destroyer forces. In this study after discution about the hydraulic jump and its resultant forces, a equation has been offerd to determine the thickness of stilling basin floor slab using buckingham theory andsoftware DATAFIT. Finaly the slab which evaluated by physical model, simulated using mathematical model(software ANSYS 10) and studied. The stress and strain diagrams were extracted. Results showed that physical and mathematical models were matched very good.

Abstract: This paper is concerned with a mathematical model for numerical simulation of 2D flow accompanied with a hydraulic jump. The governing water equations are solved by the Mac Cormack’s predictor-corrector technique. The mathematical model is used to numerically predict 2D hydraulic jump in a rectangular open channel. The comparison and the analysis show that the proposed method is accurate, reliable and effective in simulation of hydraulic jump flows.

Abstract: This paper is concerned with a mathematical model for numerical simulation of 2D flow accompanied with a hydraulic jump. The governing water equations are solved by the MacCormack’s predictor-corrector technique. The mathematical model is used to numerically predict 2D hydraulic jump in a rectangular open channel. The comparison and the analysis show that the proposed method is accurate, reliable and effective in simulation of hydraulic jump flows.