Experimental and numerical investigation of the multiphase flow in the water model of a steel ladle as basis for the enhancement of multiphase flow models in computational fluid dynamics of metallurgical reactors

行业对高性能钢的需求不断增加，这些钢具有最高的纯度和均匀的最佳工艺性能，以延长产品寿命，这需要对二次冶金工艺有全面的了解。这为提高生产效率和产品质量提供了机会。根据各种参数详细了解钢包水模型中的多相流动，可以加深对过程及其影响因素的基本理解。此外，所获得的数据可以用作进一步开发描述钢包中流动的数值模型的验证基础。在AOD转炉的研究过程中，CFD模型已经通过水模型实验进行了验证。结果表明，在转换到真实的过程后，这些模型能够再现升力自由射流的特性。研究还表明，水模型中的影响参数对真实的过程也有同样的影响。本研究项目旨在了解非均质提升自由射流形成的基本机理及其在钢包中产生的流动。这方面的知识将被应用到描述反应器在多相流领域的数值模型的发展。特别是对冶金反应器中多相流的数值描述进行全面的研究是必要的。用现代实验方法验证的数值模型在文献中并不常见，在本研究项目中，对钢包水模型中流动的各种影响因素进行了详细的实验研究。此外，基于实验数据，数值模型，能够宏观地描述复杂的过程，进一步发展。这些模型为先进的工艺改进提供了基础。正确模拟气泡尺寸分布、气泡速度和非均匀升力自由射流的形状是研究过程中能量和质量传输模型开发的关键因素（例如化学反应建模）。基于开发的模型，钢包和喷射系统的几何形状可以优化，使操作员能够缩短工艺时间。这样，可以节省能源和资源。

Increasing demands of the industry for high performance steels of highest purity and homogeneous optimal technological properties for components to increase the product life, require a comprehensive understanding of the processes in secondary metallurgy. This provides opportunities to improve the plant productivity and the product quality.A detailed knowledge of the multiphase flow in the water model of a ladle according to various parameters enhances the basic understanding of the process and its influencing factors. Furthermore, the achieved data can be used as a validation basis for the further development of numerical models describing the flow in the ladle. During investigations of an AOD converter CFD-models have been validated by water model experiments. It was found that after the transfer to the real process, these models are able to reproduce the characteristics of the lift free jet. It was also shown that influencing parameters in the water model affected the real process in the same way.This research project aims to understand the basic mechanisms of the formation of the heterogeneous lift free jet and the resulting flow in the ladle. This knowledge will be applied to the development of numerical models describing the reactor in the field of multiphase flow. Especially a comprehensive research of the numerical description of multiphase flows in metallurgical reactors is essential. Numerical models validated with modern experimental methods are not very common in literature.Within the research project various influencing factors on the flow in the water model of the ladle are experimentally investigated in detail. Moreover, based on the experimental data, numerical models, able to describe the complex process macroscopically, are further developed. These models provide a basis for advanced process improvements. A correct simulation of the bubble size distribution, the velocity of the bubbles and the shape of the heterogeneous lift free jet, are key factors for the development of models for energy and mass transport in the studied processes (eg modeling of chemical reactions). Based on the developed models the geometry of ladles and the injection systems can be optimized and enable the operator to shorten the process time. In this way, energy and resources can be saved.