SPH Open Boundary Simulation of Free-Surface Flow Over Ogee-crested Spillway

This study was conducted to compare water surface profiles with standard ogeecrested spillways. Different methods were used, such as (experimental models, numerical models, and design nomographs for the United States Army Corps of Engineers, USACE). In accordance with the USACE specifications, three different models were constructed from rigid foam and then installed in a testing flume. The water surface profile has been recorded for these models with different design heads. For modeling the experimental model configurations, a numerical model based on the smoothed particle hydrodynamics (SPH) technique was used and is developed to simulate the water surface profile of the flow over the ogee-crested spillway. A 2D SPHysics open-source software has been used in this study, using the SPH formulation to model fluid flow, developing the SPH boundary procedure to handle open-boundary simulations, and modifying the open-source SPHysics code for this purpose. The maximum absolute difference between the measured and computed results of the water surface profile for all head ratios of (H/Hd), does not exceed 4.63% at the crest region, the numerical results for the water surface profile showed good agreement with the physical model results. The results obtained experimentally and numerically by SPH are compared with the CFD results in order to be more reassuring from the results. Additional comparisons were made using interpolated data from USACE, Waterways Experiment Station (WES), and design nomographs. The SPH technique is considered very promising and effective for free surface flow applications.

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Meshless particle modelling of free surface flow over spillways

Journal of Hydroinformatics ◽

10.2166/hydro.2015.096 ◽

2015 ◽

Vol 18 (2) ◽

pp. 354-370 ◽

Cited By ~ 7

Author(s):

Ehsan Jafari-Nodoushan ◽

Khosrow Hosseini ◽

Ahmad Shakibaeinia ◽

Seyed-Farhad Mousavi

Keyword(s):

Free Surface ◽

Surface Profile ◽

Particle Method ◽

Free Surface Flow ◽

Surface Flow ◽

Weakly Compressible ◽

Wall Boundary Conditions ◽

Free Surface Profile ◽

Moving Particle ◽

Lagrangian Particle Method

A meshless Lagrangian (particle) method based on the weakly compressible moving particle semi-implicit formulation (WC-MPS) is developed and analysed for simulation of flow over spillways. To improve the accuracy of the model for pressure and velocity calculation, some modifications are proposed and evaluated for the inflow and wall boundary conditions implementation methods. The final model is applied for simulation of flow over the 45° and 60° ogee spillways (with different inflow rates) and also shallow flow over a spillway-like curved bed channel. To evaluate the model, the numerical results of free surface profile and velocity and pressure field are compared with the available experimental measurements. Comparisons show the results’ accuracy of the developed model and proposed improvements. The results of this study will not only provide a reliable numerical tool for modelling of flow over spillways, but also provide an insight for better understating flow pattern over these hydraulic structures.

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A weakly compressible MPS method for modeling of open-boundary free-surface flow

International Journal for Numerical Methods in Fluids ◽

10.1002/fld.2132 ◽

2009 ◽

pp. n/a-n/a ◽

Cited By ~ 20

Author(s):

Ahmad Shakibaeinia ◽

Yee-Chung Jin

Keyword(s):

Free Surface ◽

Free Surface Flow ◽

Surface Flow ◽

Open Boundary ◽

Mps Method ◽

Weakly Compressible

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Free Surface Flow Profile and Fluctuations of a Circular Hydraulic Jump Formed by an Impinging Jet

Journal of Fluids Engineering ◽

10.1115/1.2817322 ◽

1995 ◽

Vol 117 (4) ◽

pp. 677-682 ◽

Cited By ~ 2

Author(s):

J. W. Stevens

Keyword(s):

Free Surface ◽

Hydraulic Jump ◽

Surface Profile ◽

Free Surface Flow ◽

Surface Flow ◽

Flow Profile ◽

Flow Depth ◽

Supercritical Flow ◽

Jump Size ◽

Free Surface Profile

A fine wire probe was used to make quantitative measurements of the free surface profile and surface fluctuations around the hydraulic jump formed by a normally impinging free liquid jet. Representative magnitudes of both radial and axial fluctuations were presented for two nozzle sizes and several jet Reynolds numbers and subcritical flow depths. The results were compared to previous measurements of the supercritical flow depth and to theoretical predictions of the circular hydraulic jump size. The agreement appeared reasonable for the supercritical flow depth while the analytical expressions predicted a shorter hydraulic jump than that found by the measurements for the same supercritical flow conditions.

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Two-dimensional natural element analysis of double-free surface flow under a radial gate

Canadian Journal of Civil Engineering ◽

10.1139/l2012-046 ◽

2012 ◽

Vol 39 (6) ◽

pp. 643-653 ◽

Cited By ~ 3

Author(s):

Farhang Daneshmand ◽

S.A. Samad Javanmard ◽

Jan F. Adamowski ◽

Tahereh Liaghat ◽

Mohammad Mohsen Moshksar

Keyword(s):

Free Surface ◽

Surface Profile ◽

Free Surface Flow ◽

Surface Flow ◽

Element Analysis ◽

Pressure Distributions ◽

Free Surface Profile ◽

Natural Element ◽

Gravity Driven ◽

Radial Gate

The gravity-driven free surface flow problems for which both the solid and free surface boundaries are highly curved are very difficult to solve. A computational scheme using a variable domain and a fixed domain natural element method (NEM) is developed in the present study for the computation of the free surface profile, velocity and pressure distributions, and the flow rate of a 2D gravity fluid flow through a conduit and under a radial gate. The problem involves two highly curved unknown free surfaces and arbitrary curved-shaped boundaries. These features make the problem more complicated than flow under a sluice gate or over a weir. The fluid is assumed to be inviscid and incompressible and the results obtained are confirmed by conducting a hydraulic model test. The results are in agreement with other flow solutions for free surface profiles and pressure distributions.

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Free-surface flow due to a source submerged in a fluid of infinite depth with two stagnant regions

The Journal of the Australian Mathematical Society Series B Applied Mathematics ◽

10.1017/s033427000000895x ◽

1993 ◽

Vol 34 (3) ◽

pp. 368-376 ◽

Cited By ~ 2

Author(s):

Hocine Mekias ◽

Jean-Marc Vanden-Broeck

Keyword(s):

Free Surface ◽

Surface Profile ◽

Free Surface Flow ◽

Shear Layers ◽

Free Surface Flows ◽

Surface Flow ◽

Surface Flows ◽

Infinite Depth ◽

Free Surface Profile ◽

Series Truncation Method

AbstractTwo-dimensional free-surface flows produced by a submerged source in a fluid of infinite depth are considered. It is assumed that the point on the free surface just above the source is a stagnation point and that the fluid outside two shear layers is at rest. The free-surface profile and the shape of the shear layers are determined numerically by using a series-truncation method. It is shown that there is a solution for each value of the Froude number F > 0. When F tends to infinity, the flow also describes a thin jet impinging in a fluid at rest.

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Analysis of Open-Source CFD Tools for Simulating Complex Hydrodynamic Problems

Volume 8: CFD and FSI ◽

10.1115/omae2020-18030 ◽

2020 ◽

Author(s):

Mohd Atif Siddiqui ◽

Hui-li Xu ◽

Marilena Greco ◽

Giuseppina Colicchio

Keyword(s):

Free Surface ◽

Open Source ◽

Vortex Shedding ◽

Cfd Simulation ◽

Free Surface Flow ◽

Surface Flow ◽

Sea Waves ◽

Viscous Effects ◽

First Case ◽

Flow Effects

Abstract OpenFOAM (OF) represents an attractive and widely used open-source environment for simulating complex hydrodynamic scenarios with several implemented numerical methods and wide variety of problems it can be applied to. For commercial and open-source solvers, though, expertise and experience are required to get physical and reliable results. Here, without pretending to be exhaustive, we aim to contribute in highlighting advantages and challenges of some key computational fluid dynamics (CFD)-simulation tools, with focus on the OF platform. We examine the effect of grid type, grid size and time-evolution scheme. Dynamic-mesh techniques and their influence on local and global numerical results are discussed, as well as the use of an overset grid versus a deforming mesh. Lastly, possible error sources in CFD simulations are discussed. These numerical studies are performed investigating two complex hydrodynamic problems: 1. a fully-immersed flapping hydrofoil aimed to generate thrust, 2. a damaged and an intact ship section fixed in beam-sea waves, in forced heave and roll motion in calm water. In the first case, vortex-shedding and wake features are crucial; in the second case, free-surface flow effects play the key role while the importance of vortex-shedding and viscous-flow effects depends on the scenario. The first problem is solved with OF and validated with results from benchmark experiments. The second problem is solved using (A) OF, (B) an in-house CFD solver and (C) a fully-nonlinear potential-flow code. A and B assume laminar-flow conditions and use, respectively, a volume-of-fluid and a level-set technique to handle the free-surface evolution. C is considered to examine importance of nonlinear versus viscous effects for the examined problems. The results are compared against in-house experiments.

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Potential flow solution for a free surface flow past a sudden slope change

Canadian Journal of Civil Engineering ◽

10.1139/l04-021 ◽

2004 ◽

Vol 31 (4) ◽

pp. 553-560 ◽

Cited By ~ 2

Author(s):

A R Zarrati ◽

Yee-Chung Jin ◽

A Shanehsaz-zadeh ◽

F Ahadi

Keyword(s):

Free Surface ◽

Pressure Distribution ◽

Analytical Model ◽

Potential Flow ◽

Sudden Change ◽

Surface Profile ◽

Free Surface Flow ◽

Surface Flow ◽

Flow Past ◽

Model Predictions

An analytical model was developed to calculate the pressure distribution in a free surface flow past a sudden change in channel slope. A conformal transformation technique was used to solve the problem analytically in a way that there is no need for trial and error to find the location of the free surface. Two methods were employed for this simulation: flow at a corner and free streamline theory. It was shown that free streamline theory is more accurate. Experiments were conducted to verify the ability of the analytical model to calculate the pressure distribution in a channel with a sudden change in slope. Slope changes of 6.22°, 10°, and 15° were tested with various flow discharges. The analytical model predictions of pressure distribution along the channel bed and with depth agreed well with the experimental measurements. Pressures up to 25 times the hydrostatic pressure were experimentally measured near the point of sudden change in slope. These pressures were reproduced by the model. The analytical model predictions of the water surface profile over a ramp in a prototype spillway were compared with those of a numerical model. The comparison showed a good agreement.Key words: pressure distribution, free surface flow, analytical model, chute spillway, aerator ramp, potential flow.

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