Run-out table bottom jet cooling

跳动台底部喷射冷却

• 批准号: 459359-2013
• 负责人: Militzer, Matthias
• 金额: $ 4.37万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=618402
• 关键词: Run; out; table; bottom; jet

There has been a tremendous development of advanced steels over the past few decades to provide steel products with improved properties for a wide range of applications including automotive, energy and construction. These advancements by steelmakers were critically enabled by design of innovative processing paths and better process control. Here, the development of process models has had a significant impact. For hot rolled steels cooling by water sprays on the run-out table is a key metallurgical tool to tailor the properties of the steel. During the cooling the phase transformation occurs from austenite with a face-centred cubic (FCC) crystal structure to ferrite with a body-centred cubic (BCC) crystal structure. In detail, depending on steel chemistry and processing path, different transformation products can be obtained to create complex multi-phase microstructures which offer new paradigms for the design of properties. To realize this potential it is critical to control the cooling path precisely as this determines the phase transformation kinetics and the resulting microstructures. Cooling of hot moving steel sheets by water is a complex transient heat transfer problem including nucleate, transition and film boiling regimes. Current run-out table cooling models are to a large degree empirical in nature. There is a need to develop more fundamentally based models. Research in this area has so far emphasized top surface cooling whereas bottom jet cooling studies have received far less attention. Thus, the proposed project is designed to provide a systematic bottom jet cooling study to develop a cooling model for bottom jets that rigorously accounts for the underlying boiling mechanisms. The project is conducted in collaboration with ArcelorMittal Dofasco - Canada's leader in the production of automotive steel sheets. Experimental studies will be carried on a pilot scale run-out table facility to provide guidance for the model development. The proposed heat transfer correlations will then be incorporated into an existing hot strip mill process model of ArcelorMittal Dofasco such that the model can be validated with industrial data. The project offers training opportunities for three graduate students.

过去几十年来，先进钢材取得了巨大发展，为汽车、能源和建筑等广泛应用提供了性能改进的钢材产品。钢铁制造商取得的这些进步很大程度上得益于创新加工路径的设计和更好的过程控制。在这里，流程模型的发展产生了重大影响。对于热轧钢来说，在输出台上喷水冷却是调整钢性能的关键冶金工具。在冷却过程中，发生从具有面心立方（FCC）晶体结构的奥氏体到具有体心立方（BCC）晶体结构的铁素体的相变。具体来说，根据钢铁化学和加工路径，可以获得不同的转变产物，以创建复杂的多相微观结构，为性能设计提供新的范例。为了实现这一潜力，精确控制冷却路径至关重要，因为这决定了相变动力学和由此产生的微观结构。水冷却热运动钢板是一个复杂的瞬态传热问题，包括形核、转变和膜沸腾状态。目前的输出台冷却模型在很大程度上是经验性的。需要开发更基础的模型。迄今为止，该领域的研究强调顶部表面冷却，而底部喷射冷却研究受到的关注要少得多。因此，所提议的项目旨在提供系统的底部喷射冷却研究，以开发底部喷射冷却模型，该模型严格解释了潜在的沸腾机制。该项目是与加拿大汽车钢板生产领导者安赛乐米塔尔多法斯科公司合作进行的。实验研究将在中试规模的跳动台设施上进行，为模型开发提供指导。然后，所提出的传热相关性将被纳入 ArcelorMittal Dofasco 现有的热带钢轧机工艺模型中，以便可以使用工业数据验证该模型。 The project offers training opportunities for three graduate students.