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In our earlier work (https://github.com/rpsuark/ASEE21-OpenFOAM-Introduction), it was reasoned that open-source software OpenFOAM would be a cost-effective and more accessible alternative for teaching Computational Fluid Dynamics (CFD) than commercial software. Commercial software like Ansys Fluent costs more than $10k per year for one user. The above-mentioned work models wind flow around a building for smooth flow, whereas extreme winds, which tend to be irregular, can cause various structural failures of buildings. These kinds of irregular wind flows are called turbulent flows. Thus, in this contribution, an additional three-week class module is provided for the ‘CFD for Wind Engineering’ class which includes hands-on material on modeling turbulent wind flow around a building using open-source software OpenFOAM and ParaView. To model the turbulence, Large Eddy Simulation (LES) is considered with a logarithmic inlet profile. To connect the log profile in a coarse grid, the law of the wall condition is also introduced in the OpenFOAM environment. To illustrate the application, the wind flow around a cubic building is considered. The current study’s case files and the extended report are provided at https://github.com/rpsuark/ASEE21-OpenFOAM-LES.
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This content will become publicly available on May 1, 2025
Mixing Time Prediction in a Ladle Furnace
This paper presents a study on the effectiveness of two turbulence models, the large eddy simulation (LES) model and the k-ε turbulence model, in predicting mixing time within a ladle furnace using the computational fluid dynamics (CFD) technique. The CFD model was developed based on a downscaled water ladle from an industrial ladle. Corresponding experiments were conducted to provide insights into the flow field, which were used for the validation of CFD simulations. The correlation between the flow structure and turbulence kinetic energy in relation to mixing time was investigated. Flow field results indicated that both turbulence models aligned well with time-averaged velocity data from the experiments. However, the LES model not only offered a closer match in magnitude but also provided a more detailed representation of turbulence eddies. With respect to predicting mixing time, increased flow rates resulted in extended mixing times in both turbulence models. However, the LES model consistently projected longer mixing times due to its capability to capture a more intricate distribution of turbulence eddies.
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- Award ID(s):
- 2113967
- PAR ID:
- 10533599
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Metals
- Volume:
- 14
- Issue:
- 5
- ISSN:
- 2075-4701
- Page Range / eLocation ID:
- 518
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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