scholarly journals Numerical Investigation of the Hydrodynamic Conditions in A Multi-Strand Cc Tundish with Closed Outlets

2014 ◽  
Vol 59 (3) ◽  
pp. 887-892 ◽  
Author(s):  
T. Merder
Keyword(s):  
Liquid Steel ◽  
Stokes Equations ◽  
Thermal Conditions ◽  
Casting Process ◽  
Navier Stokes ◽  
Hydrodynamic Conditions ◽  
Continuous Casting Process ◽  
Navier Stokes Equations ◽  
Steel Flow ◽  
Kinetics Of

Abstract In industrial conditions there are situations when the CC machine works under emergency. It can be result of mechanical or electrical causes, breakout of billet or problem with supplying new parts of liquid steel to the CC machine. As a consequence one or two outlets of the tundish should be closed. However, closing one of the outlets influences the hydrodynamic and thermal conditions occurring in the tundish. Thus, the important information is which of the outlets should be closed to conduct further continuous casting process correctly.The following research was conducted to analyze the influence of liquid steel flow behaviour in the multi-strand tundish when all outlets do not work. Such problem was solved by means of numerical methods based on Navier-Stokes equations (k–ɛ standard turbulence model). Numerical simulations were done using the educational version of CFD program (Computational Fluid Dynamics) – ANSYSFluent. As a result forecasted velocity fields and RTD curves (Residence Time Distribution) were obtained. RTD characteristics were used to determine kinetics of liquid steel mixing and also to calculate parts of particular flow areas for studied cases.

scholarly journals Investigation of the Flow Structure in the Tundish with the Use of Rans and Les Methods

2015 ◽  
Vol 60 (1) ◽  
pp. 215-220 ◽  
Author(s):  
M. Warzecha ◽  
T. Merder ◽  
P. Warzecha
Keyword(s):  
Numerical Modeling ◽  
Numerical Simulations ◽  
Flow Structure ◽  
Liquid Steel ◽  
Stokes Equations ◽  
Substantial Effect ◽  
Test Facility ◽  
Navier Stokes ◽  
Model Studies ◽  
Steel Flow

AbstractThe liquid steel flow structure in the tundish has a very substantial effect on the quality of the final product and on efficient casting conditions. Numerous model studies are being carried out to explain the effect of the tundish working conditions on casting processes.It is necessary to analyze the structure of liquid steel flow, which is strongly supported with numerical modeling. In numerical modeling, a choice of a proper turbulence model is crucial as it has a great impact on the flow structure of the fluid in the analyzed test facility. So far most numerical simulations has been done using RANS method (Reynolds-averaged Navier-Stokes equations) but in that case one get information about the averaged values of the turbulent flow. In presented study, numerical simulations using large eddy simulations (LES) method were used and compared to RANS results. In both cases, numerical simulations are carried out with the finite-volume commercial code AnsysFluent.

Lattice Boltzmann Model for Incompressible Axisymmetric Thermal Flows With Swirl

2018 ◽  
Author(s):  
Insaf Mehrez ◽  
Ramla Gheith ◽  
Fethi Aloui ◽  
Samia Ben Nasrallah
Keyword(s):  
Lattice Boltzmann ◽  
Stokes Equations ◽  
Thermal Conditions ◽  
Analytic Solutions ◽  
Lattice Boltzmann Model ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Wall Boundary Conditions ◽  
Physical Phenomena ◽  
Thermal Flows

This paper presents a Lattice Boltzmann (LB) model for incompressible axisymmetric thermal flows. The forces and source terms are added into the Lattice Boltzmann Equation (LBE) and the incompressible Navier-Stokes equations are recovered by the Chapman-Enskog expansion. The model of Zhou [1] is applied for axial, radial and azimuthal velocities and the model of Q.Li et al [2] is computed for temperature variation. The source term of the scheme is simple and without velocity gradient terms. This approach can solve problems including several physical phenomena and complicated force forms as the flow between two coaxial cylinders. Good agreement is obtained between the present work, the analytic solutions and results of previous studies in cylindrical pipe. It proves the efficiency and simplicity of the proposed model compared to other ones. The Taylor-Couette (TC) system is treated with water flow characterized by a radius ratio η = 0.5 and an aspect ratio Γ = 3.8. Three Reynolds numbers of 85, 100 and 150 are tested. The influence of the end-wall boundary conditions and the influence of thermal conditions on the flow structure and on the temperature distribution along the inner and outer cylinders are analyzed.

scholarly journals Modelling Liquid Steel Motion Caused by Electromagnetic Stirring in Continuous Casting Steel Process

2014 ◽  
Vol 59 (2) ◽  
pp. 487-492 ◽  
Author(s):  
M. Rywotycki ◽  
Z. Malinowski ◽  
J. Giełżecki ◽  
A. Gołdasz
Keyword(s):  
Liquid Steel ◽  
Stokes Equations ◽  
Computation Time ◽  
Electromagnetic Stirring ◽  
Navier Stokes ◽  
The Finite Element Method ◽  
Navier Stokes Equations ◽  
Stationary Heat Conduction ◽  
Casting Steel ◽  
Reduce Computation Time

Abstract The paper presents an attempt of modelling liquid steel motion triggered off by electromagnetic stirring. Steel viscosity was calculated on the basis of temperature field determined with the use of stationary heat conduction equation. Velocity field was determined using Navier-Stokes equations and stream continuity equation. Solution was obtained using the finite element method. The developed model allows to carry out quick simulating calculations of fluid flow. Stationary solution was employed, and this allowed to reduce computation time substantially.

scholarly journals Numerical Prediction of Hydrodynamic Conditions in one Strand Tundish. Influence of Thermal Conditions and Casting Speed/ Numeryczna Prognoza Warunków Hydrodynamicznych W Jednozyłowej Kadzi Posredniej. Wpływ Warunków Cieplnych I Predkosci Odlewania

2014 ◽  
Vol 59 (4) ◽  
pp. 1249-1256
Author(s):  
A. Cwudzinski
Keyword(s):  
Computer Simulations ◽  
Casting Speed ◽  
Liquid Steel ◽  
Thermal Conditions ◽  
Hydrodynamic Conditions ◽  
Ansys Fluent ◽  
Working Space ◽  
Flow Control Devices ◽  
Pattern Forming ◽  
Steel Flow

Abstract This paper reports the results of computer simulations of the flow of liquid steel in a single-nozzle tundish, which describe the flow hydrodynamics, depending on the thermal conditions and casting speed. In this paper, five casting speeds, namely 0.3, 0.6, 0.9, 1.2 and 1.5 m/min., have been examined. In view of the fact that tundishes are being equipped with various flow control devices and the process of creating specific hydrodynamic conditions is influenced also by the temperature gradient, computer simulations of liquid steel flow under isothermal and non-isothermal conditions were performed. Computer simulations of liquid steel flow were performed using the commercial program Ansys-Fluent ®. In order to explain the phenomena occurring in the tundish working space, the buoyancy number (Bu) has been calculated. The next research step in the analysis of the flow pattern forming in different casting conditions was to record the E and F-type RTD characteristics and to describe the pattern of flow.

scholarly journals Optimal control of buoyancy-driven liquid steel stirring modeled with single-phase Navier–Stokes equations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ulrich Wilbrandt ◽  
Najib Alia ◽  
Volker John
Keyword(s):  
Liquid Steel ◽  
Gas Flow ◽  
Single Phase ◽  
Stokes Equations ◽  
Continuous Optimization ◽  
Navier Stokes ◽  
Optimization Approach ◽  
Navier Stokes Equations ◽  
Eddy Simulation ◽  
Les Model

AbstractGas stirring is an important process used in secondary metallurgy. It allows to homogenize the temperature and the chemical composition of the liquid steel and to remove inclusions which can be detrimental for the end-product quality. In this process, argon gas is injected from two nozzles at the bottom of the vessel and rises by buoyancy through the liquid steel thereby causing stirring, i.e., a mixing of the bath. The gas flow rates and the positions of the nozzles are two important control parameters in practice. A continuous optimization approach is pursued to find optimal values for these control variables. The effect of the gas appears as a volume force in the single-phase incompressible Navier–Stokes equations. Turbulence is modeled with the Smagorinsky Large Eddy Simulation (LES) model. An objective functional based on the vorticity is used to describe the mixing in the liquid bath. Optimized configurations are compared with a default one whose design is based on a setup from industrial practice.

Effects of stator splitter blades on aerodynamic performance of a single-stage transonic axial compressor

2020 ◽  
Vol 14 (4) ◽  
pp. 7369-7378
Author(s):  
Ky-Quang Pham ◽  
Xuan-Truong Le ◽  
Cong-Truong Dinh
Keyword(s):  
Stokes Equations ◽  
Three Dimensional ◽  
Axial Compressor ◽  
Aerodynamic Performance ◽  
Numerical Results ◽  
Single Stage ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Operating Stability ◽  
Length Coverage

Splitter blades located between stator blades in a single-stage axial compressor were proposed and investigated in this work to find their effects on aerodynamic performance and operating stability. Aerodynamic performance of the compressor was evaluated using three-dimensional Reynolds-averaged Navier-Stokes equations using the k-e turbulence model with a scalable wall function. The numerical results for the typical performance parameters without stator splitter blades were validated in comparison with experimental data. The numerical results of a parametric study using four geometric parameters (chord length, coverage angle, height and position) of the stator splitter blades showed that the operational stability of the single-stage axial compressor enhances remarkably using the stator splitter blades. The splitters were effective in suppressing flow separation in the stator domain of the compressor at near-stall condition which affects considerably the aerodynamic performance of the compressor.

Sign in / Sign up

Export Citation Format

Share Document