Study of Transient Flow Structures in the Continuous Casting of Steel

这项工作是建立钢坯连铸过程中瞬态流体流动的数学模型，用测量来验证它们，并应用它们来详细了解缺陷是如何形成的，以便改进工艺。在美国每年生产的1亿吨钢铁中，连铸占89%。高产量、低利润率的钢铁行业能否持续生存，取决于在提高效率的同时提高钢铁产品的质量。工厂观察发现，许多严重的质量问题与霉菌区域的流动模式直接相关。这种流动具有强湍流性，并具有大尺度非定常再循环的特点。对流动物理的更好理解将有助于改进过程建模和未来的优化。由于有许多不同的操作需要优化，该行业无法再承受传统的试错方法。该项目将推进大涡模拟流建模的最新技术，该技术以前没有处理过如此复杂的过程。这些模型将通过在研究实验室和共同赞助这项工作的钢铁公司财团的工厂中获得的实验测量进行校准和验证。然后，基于从模型应用中获得的改进的基本理解，改进的喷嘴设计和操作条件将最大限度地减少缺陷。在未来，随着薄板坯和带状连铸工艺的不断发展，在这项工作中开发的计算工具也可以应用于这些新工艺。

DMI -9800274 Thomas This work is to develop mathematical models of transient fluid flow in the continuous casting of steel slabs, validate them with measurements, and apply them to provide a detailed understanding of how defects form, so that the process can be improved. Continuous casting accounts for 89 percent of the 100 million tons of steel produced each year in the United States. Continued viability of the high-volume-low-profit-margin steel industry depends on improving the quality of the steel product while also increasing efficiency. Plant observations have found that many serious quality problems are directly associated with the flow pattern in the mold region. This flow is highly turbulent, and is characterized by large scale unsteady recirculation. A better understanding of the flow physics would enable improvements to process modeling and future optimization. With many different operations to optimize, the industry can no longer afford the traditional trial-and-error approach. This project will advance the state-of-the-art of Large-Eddy-Simulation flow modeling, which has not previously addressed a process of this complexity. The models will be calibrated and validated through experimental measurements obtained in both the research labs and plants of a consortium of steel companies, who are cosponsoring this work. Then, based on the improved fundamental understanding gained from model application, improved nozzle designs and operating conditions that minimize defects will be found. In the future, as thin slab and strip casting processes continue to be developed, the computational tools developed in this work can be applied to these new processes as well.