scholarly journals RANS versus Scale Resolved Approach for Modeling Turbulent Flow in Continuous Casting of Steel

Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1140
Author(s):  
Jurij Gregorc ◽  
Ajda Kunavar ◽  
Božidar Šarler

Numerical modeling is the approach used most often for studying and optimizing the molten steel flow in a continuous casting mold. The selection of the physical model might very much influence such studies. Hence, it is paramount to choose a proper model. In this work, the numerical results of four turbulence models are compared to the experimental results of the water model of continuous casting of steel billets using a single SEN port in a downward vertical orientation. Experimental results were obtained with a 2D PIV (Particle Image Velocimetry) system with measurements taken at various cut planes. Only hydrodynamic effects without solidification are considered. The turbulence is modeled using the RANS (Realizable k-ε, SST k-ω), hybrid RANS/Scale Resolved (SAS), and Scale Resolved approach (LES). The models are numerically solved by the finite volume method, with volume of fluid treatment at the free interface. The geometry, boundary conditions, and material properties were entirely consistent with those of the water model experimental study. Thus, the study allowed a detailed comparison and validation of the turbulence models used. The numerical predictions are compared to experimental data using contours of velocity and velocity plots. The agreement is assessed by comparing the lateral dispersion of the liquid jet in a streamwise direction for the core flow and the secondary flow behavior where recirculation zones form. The comparison of the simulations shows that while all four models capture general flow features (e.g., mean velocities in the temporal and spatial domain), only the LES model predicts finer turbulent structures and captures temporal flow fluctuations to the extent observed in the experiment, while SAS bridges the gap between RANS and LES.

Author(s):  
Luca Mangani ◽  
A. Andreini

This paper is aimed at showing the performances obtained with an open-source CFD code for heat transfer predictions after the addiction of specific modules. The development steps to make this code suitable for such simulations are described in order to point out its potentiality as a customizable CFD tool, appropriate for both academic and industrial research. The C++ library, named OpenFOAM, offers specific class and polyhedral finite volume operators thought for continuum mechanics simulations as well as built-in solvers and utilities. To make it robust, fast and reliable for RANS heat transfer predictions it was indeed necessary to implement additional submodules. The package coded by the authors within the OpenFOAM environment includes a suitable algorithm for compressible steady-state analysis. A SIMPLE like algorithm was specifically developed to extend the operability field to a wider range of Mach numbers. A set of Low-Reynolds eddy-viscosity turbulence models, chosen amongst the best performing in wall bounded flows, were developed. In addition an algebraic anisotropic correction, to increase jets lateral spreading, and an automatic wall treatment, to obtain mesh independence, were added. The results presented cover several types of flows amongst the most typical for turbomachinery and combustor gas turbine cooling devices. Impinging jets were investigated as well as film and effusion cooling flows, both in single and multi-hole configuration. Numerical predictions for wall effectiveness and wall heat transfer coefficient were tested against standard literature and in-house set-up experimental results. The numerical predictions obtained proves to be in-line with the equivalent models of commercial CFD packages obtaining a general good agreement with the experimental results. Moreover during the tests OpenFOAM code has shown a good accuracy and robustness, as well as an high flexibility in the implementation of user-defined submodules.


2010 ◽  
Vol 154-155 ◽  
pp. 840-845 ◽  
Author(s):  
Xin Xie ◽  
Deng Fu Chen ◽  
Qiang Liu ◽  
Jia Long Shen ◽  
Zheng Peng ◽  
...  

Submerged entry nozzle (SEN) bottom structure plays an important role in determining the flow pattern in continuous casting process. This work applies a water model to evaluate the pointed-bottom, flat-bottom and recessed-bottom nozzle performance in ultra-thick slab mold. The jet properties and surface flow are compared for the three kinds of nozzles quantitatively. The results show that flat-bottom and recessed-bottom nozzles are similar in flow pattern, but the pointed-bottom nozzle has smaller jet angle, thinner flow pattern, larger surface asymmetry rate, and higher surface flow intensity.


2005 ◽  
Vol 45 (11) ◽  
pp. 1626-1635 ◽  
Author(s):  
Raul MIRANDA ◽  
Miguel Angel BARRON ◽  
Jose BARRETO ◽  
Luis HOYOS ◽  
Jesus GONZALEZ

2012 ◽  
Vol 538-541 ◽  
pp. 1076-1079
Author(s):  
Xing Juan Wang ◽  
Li Guang Zhu ◽  
Ran Liu ◽  
Zhi Hao Li ◽  
Peng Tian

Using finite element method, the molten steel flow process in soft-contact electromagnetic continuous casting mold is simulated. The results show that the molten steel surface were affected by the electromagnetic force and shrink to the centre, near meniscus zone the flow velocity of steel increases and appears an obvious circumfluence, a large number of inclusion float and are absorbed by flux; on the other hand, the turbulent kinetic energy significant increases in circumfluence area, this exacerbates the reaction between flux and liquid steel, the initial size of the solidification organization are refined, and the surface quality of slab are enhanced.


2015 ◽  
Vol 86 (4) ◽  
pp. 400-410 ◽  
Author(s):  
Christoph Kratzsch ◽  
Klaus Timmel ◽  
Sven Eckert ◽  
Rüdiger Schwarze

Sign in / Sign up

Export Citation Format

Share Document