Assessment of spillway modeling using computational fluid dynamics

Throughout the design and planning period for future hydroelectric generating stations, hydraulic engineers are increasingly integrating computational fluid dynamics (CFD) into the process. As a result, hydraulic engineers are interested in the reliability of CFD software to provide accurate flow data for a wide range of structures, including a variety of different spillways. In the literature, CFD results have generally been in agreement with physical model experimental data. Despite past success, there has not been a comprehensive assessment that looks at the ability of CFD to model a range of different spillway configurations, including flows with various gate openings. In this article, Flow-3D is used to model the discharge over ogee-crested spillways. The numerical model results are compared with physical model studies for three case study evaluations. The comparison indicates that the accuracy of Flow-3D is related to the parameter P/Hd.

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Effects of Over Fire Air on the Combustion and NOx Emission Characteristics of a 600 MW Opposed Swirling Fired Boiler

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.512-515.2135 ◽

2012 ◽

Vol 512-515 ◽

pp. 2135-2142 ◽

Cited By ~ 5

Author(s):

Yu Peng Wu ◽

Zhi Yong Wen ◽

Yue Liang Shen ◽

Qing Yan Fang ◽

Cheng Zhang ◽

...

Keyword(s):

Fluid Dynamics ◽

Experimental Data ◽

Empirical Method ◽

Nox Emission ◽

Emission Characteristics ◽

Cfd Model ◽

Nitrogen Release ◽

Computational Fluid Dynamics Cfd ◽

Low Nox Emission

A computational fluid dynamics (CFD) model of a 600 MW opposed swirling coal-fired utility boiler has been established. The chemical percolation devolatilization (CPD) model, instead of an empirical method, has been adapted to predict the nitrogen release during the devolatilization. The current CFD model has been validated by comparing the simulated results with the experimental data obtained from the boiler for case study. The validated CFD model is then applied to study the effects of ratio of over fire air (OFA) on the combustion and nitrogen oxides (NOx) emission characteristics. It is found that, with increasing the ratio of OFA, the carbon content in fly ash increases linearly, and the NOx emission reduces largely. The OFA ratio of 30% is optimal for both high burnout of pulverized coal and low NOx emission. The present study provides helpful information for understanding and optimizing the combustion of the studied boiler

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A Study on the Performance of Stratified Air Conditioning Design in Assembly Halls – A Case Study at the Dazhi Cultural Center in Taiwan

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.368-370.599 ◽

2013 ◽

Vol 368-370 ◽

pp. 599-602 ◽

Cited By ~ 1

Author(s):

Ian Hung ◽

Hsien Te Lin ◽

Yu Chung Wang

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Indoor Air ◽

Air Conditioning ◽

Cfd Simulation ◽

Indoor Temperature ◽

Cultural Center ◽

Computational Fluid Dynamics Cfd

This study focuses on the performance of air conditioning design at the Dazhi Cultural Center and uses a computational fluid dynamics (CFD) simulation to discuss the differences in wind velocity and ambient indoor temperature between all-zone air conditioning design and stratified air conditioning design. The results have strong implications for air conditioning design and can improve the indoor air quality of assembly halls.

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Modelling of working processes of non-contact oil free vacuum pumps by computational fluid dynamics (CFD) methods

Journal of Physics Conference Series ◽

10.1088/1742-6596/2059/1/012003 ◽

2021 ◽

Vol 2059 (1) ◽

pp. 012003

Author(s):

A Burmistrov ◽

A Raykov ◽

S Salikeev ◽

E Kapustin

Keyword(s):

Fluid Dynamics ◽

Experimental Data ◽

Computational Fluid Dynamics ◽

Mathematical Models ◽

Cfd Models ◽

Ansys Cfx ◽

Sst Turbulence Model ◽

Computational Fluid Dynamics Cfd ◽

Dynamic Meshing ◽

Comparison With Experimental Data

Abstract Numerical mathematical models of non-contact oil free scroll, Roots and screw vacuum pumps are developed. Modelling was carried out with the help of software CFD ANSYS-CFX and program TwinMesh for dynamic meshing. Pumping characteristics of non-contact pumps in viscous flow with the help of SST-turbulence model were calculated for varying rotors profiles, clearances, and rotating speeds. Comparison with experimental data verified adequacy of developed CFD models.

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Computational Fluid Dynamics Techniques for Flows in Lapple Cyclone Separator

Materials Science Forum ◽

10.4028/www.scientific.net/msf.498-499.179 ◽

2005 ◽

Vol 498-499 ◽

pp. 179-185

Author(s):

A.F. Lacerda ◽

Luiz Gustavo Martins Vieira ◽

A.M. Nascimento ◽

S.D. Nascimento ◽

João Jorge Ribeiro Damasceno ◽

...

Keyword(s):

Fluid Dynamics ◽

Experimental Data ◽

Computational Fluid Dynamics ◽

Turbulent Flow ◽

Reynolds Stress ◽

Cyclone Separator ◽

Two Dimensional ◽

Stress Components ◽

Computational Fluid Dynamics Cfd

A two-dimensional fluidynamics model for turbulent flow of gas in cyclones is used to evaluate the importance of the anisotropic of the Reynolds stress components. This study presents consisted in to simulate through computational fluid dynamics (CFD) package the operation of the Lapple cyclone. Yields of velocity obtained starting from a model anisotropic of the Reynolds stress are compared with experimental data of the literature, as form of validating the results obtained through the use of the Computational fluid dynamics (Fluent). The experimental data of the axial and swirl velocities validate numeric results obtained by the model.

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Computational Fluid Dynamics (CFD) Study of the 4th Generation Prototype of a Continuous Flow Ventricular Assist Device (VAD)

Journal of Biomechanical Engineering ◽

10.1115/1.1688776 ◽

2004 ◽

Vol 126 (2) ◽

pp. 180-187 ◽

Cited By ~ 32

Author(s):

Xinwei Song ◽

Houston G. Wood ◽

Don Olsen

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Blood Flow ◽

Ventricular Assist Device ◽

Continuous Flow ◽

Surrounding Tissue ◽

Assist Device ◽

Ventricular Assist ◽

Wide Range ◽

Computational Fluid Dynamics Cfd

The continuous flow ventricular assist device (VAD) is a miniature centrifugal pump, fully suspended by magnetic bearings, which is being developed for implantation in humans. The CF4 model is the first actual prototype of the final design product. The overall performances of blood flow in CF4 have been simulated using computational fluid dynamics (CFD) software: CFX, which is commercially available from ANSYS Inc. The flow regions modeled in CF4 include the inlet elbow, the five-blade impeller, the clearance gap below the impeller, and the exit volute. According to different needs from patients, a wide range of flow rates and revolutions per minute (RPM) have been studied. The flow rate-pressure curves are given. The streamlines in the flow field are drawn to detect stagnation points and vortices that could lead to thrombosis. The stress is calculated in the fluid field to estimate potential hemolysis. The stress is elevated to the decreased size of the blood flow paths through the smaller pump, but is still within the safe range. The thermal study on the pump, the blood and the surrounding tissue shows the temperature rise due to magnetoelectric heat sources and thermal dissipation is insignificant. CFD simulation proved valuable to demonstrate and to improve the performance of fluid flow in the design of a small size pump.

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CFD Modelling of Multiphase Flows: An Overview

Emerging Technology in Fluids, Structures, and Fluid Structure Interactions ◽

10.1115/pvp2003-1951 ◽

2003 ◽

Cited By ~ 1

Author(s):

Rajnish K. Calay ◽

Arne E. Holdo

Keyword(s):

Fluid Dynamics ◽

Mass Transfer ◽

Computational Fluid Dynamics ◽

Numerical Modeling ◽

Mathematical Models ◽

Cfd Modelling ◽

Two Phase ◽

Wide Range ◽

Computational Fluid Dynamics Cfd ◽

Numerical Modeling Of Flows

The Computational Fluid Dynamics (CFD) is now increasingly being used for modeling industrial flows, i.e. flows which are multiphase and turbulent. Numerical modeling of flows where momentum, heat and mass transfer occurs at the interface presents various difficulties due to the wide range of mechanisms and flow scenarios present. This paper attempts to provide a summary of available mathematical models and techniques for two-phase flows. Some comments are also made on the models available in the commercially available codes.

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Evaluation of Seabed Stability and Scour Control Around Subsea Gravity Protection Structures

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 4 ◽

10.1115/omae2010-20999 ◽

2010 ◽

Cited By ~ 2

Author(s):

Richard J. S. Whitehouse ◽

Carlos Lam ◽

Stephen Richardson ◽

Peter Keel

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

North Sea ◽

Cfd Analysis ◽

Cfd Model ◽

3 Dimensional ◽

Computational Fluid Dynamics Cfd ◽

The Uk ◽

Study Application

Results from an advanced 3-dimensional Computational Fluid Dynamics (CFD) model have proven to form an effective basis on which to design stable and scour resistant subsea structures in areas of seabed which are prone to scouring. A case study application from the UK sector of the southern North Sea is presented to demonstrate the benefits of the CFD analysis.

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A Study of Aerodynamics Force Evaluation of Horizontal Axis Wind Turbine (HAWT) Blade Using 2D and 3D Comparison

ASME 2015 Power Conference ◽

10.1115/power2015-49222 ◽

2015 ◽

Author(s):

Nazia Binte Munir ◽

Kyoungsoo Lee ◽

Ziaul Huque ◽

Raghava R. Kommalapati

Keyword(s):

Fluid Dynamics ◽

Experimental Data ◽

Computational Fluid Dynamics ◽

Wind Turbine ◽

Blade Surface ◽

Aerodynamic Forces ◽

Horizontal Axis Wind Turbine ◽

Computational Fluid Dynamics Cfd ◽

Experimental Values ◽

Nrel Phase Vi

The main purpose of the paper is to use Computational Fluid Dynamics (CFD) in 3-D analysis of aerodynamic forces of a Horizontal Axis Wind Turbine (HAWT) blade and compare the 3-D results with the 2-D experimental results. The National Renewable Energy Laboratory (NREL) Phase VI wind blade profile is used as a model for the analysis. The results are compared with the experimental data obtained by NREL at NASA Ames Research Center for the NREL Phase VI wind turbine blade. The aerodynamic forces are evaluated using 3-D Computational Fluid Dynamics (CFD) simulation. The commercial ANSYS CFX and parameterized 3-D CAD model of NREL Phase VI are used for the analysis. The Shear Stress Transport (SST) Gamma-Theta turbulence model and 0-degree yaw angle condition are adopted for CFD analysis. For the case study seven varying wind speeds (5 m/s, 7 m/s, 10 m/s, 13 m/s, 15 m/s, 20 m/s, 25 m/s) with constant blade rotational speed (72 rpm) are considered. To evaluate the 3-D aerodynamic effect sectional pressure coefficient (Cp) and integrated forces about primary axis such as normal, tangential, thrust and torque are evaluated for each of the seven wind speed cases and compared with the NREL experimental values. The numerical difference of values on wind blade surface between this study and 3-D results of NREL wind tunnel test are found negligible. The paper represents an important comparison between the 3-D lift & drag coefficient with the NREL 2-D experimental data. The results shows that though the current study is in good agreement with NREL 3-D experimental values there is large deviation between the NREL 2-D experimental data and current 3-D study which suggests that in case of 3-D analysis of aerodynamic force of blade surface it is better to use NREL 3-D values instead of 2-D experimental values.

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Verification and validation of a computational fluid dynamics (CFD) model for air entrainment at spillway aerators

Canadian Journal of Civil Engineering ◽

10.1139/l09-017 ◽

2009 ◽

Vol 36 (5) ◽

pp. 826-836 ◽

Cited By ~ 26

Author(s):

M. Cihan Aydin ◽

Mualla Ozturk

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Physical Model ◽

Scale Effects ◽

Air Entrainment ◽

Cfd Modeling ◽

Policy Statement ◽

Numerical Verification ◽

Empirical Equations ◽

Computational Fluid Dynamics Cfd

The results of computational fluid dynamics (CFD) modeling obtained by using FLUENT software with respect to the air entrainment at spillway aerators are compared with data from a physical model study, as well as the results of some empirical equations and prototype observations presented by other investigators. The air-entrainment rates obtained from the CFD analyses are in reasonable agreement with the prototype data and the values calculated from empirical equations, and are better than the physical model data, which include considerable scale effects. The numerical verification procedure in this study is based on the American Society of Mechanical Engineers (ASME) editorial policy statement, which provides a framework for CFD uncertainty analysis. Thus, validation of the CFD is discussed within the scope of this study.

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