Session: 11-19-01: Methods in Computational Heat Transfer and Their Applications

Paper Number: 145700

145700 - Investigating the Effects of Spray Nozzle Clogging in Continuous Casting of Steel 

In the steel industry, molten steel is solidified into slab, billet, or bloom through a continuous casting process. The molten steel is cooled through water-cooled copper mold where the steel the directly touches the mold surface solidifies, forming a thin solid shell.  The solid shell thickness continues to grow as the slab with thin solid shell and liquid steel at the core is cooled further by water sprays injected by air-mist nozzles in the secondary cooling section of the caster. These air-mist nozzles play a crucial role in maintaining the desired thermal conditions, ensuring that the steel cools at an appropriate rate to achieve the necessary physical properties. Optimal cooling is crucial to ensure proper solidification rate to produce good quality cast product.  However, poor spray water quality can easily cause the fine nozzle orifice to clog, reducing the cooling efficiency and, consequently, product quality.

This study aims to investigate the effects of nozzle clogging on heat transfer behavior during continuous casting. An integrated three-dimensional computational fluid dynamics (CFD) model to explore the effects of nozzle clogging on the steel solidification. The enthalpy-porosity methods is employed to model the solidification process.

The cooling provide by the air-mist nozzles on the slab surface is defined using heat transfer coefficient (HTC) correlation developed in a previous study.  The HTC distribution for each individual nozzle is defined using the HTC correlation. These individual HTC profiles are then arranged based on the nozzle locations on the caster to provide complete and realistic boundary conditions for the CFD model.  The effects of clogging at different locations along the caster are investigated. Natural convection and radiative heat transfer are used as boundary conditions at the clogged nozzle locations.

Through a detailed examination of changes in slab surface temperature, cooling rates, and metallurgical length, the study seeks to uncover the complex interplay between nozzle clogging and its consequent impacts on the solidification patterns of the cast product. The findings reveal that nozzle clogging increases surface temperature by up to 100 K and modestly extends the metallurgical length (ML), with more clogs leading to longer ML. Clogs near the meniscus are particularly impactful, highlighting the impact of cooling in the early stage of solidification. Even a single clogged nozzle can notably influence solidification, with up to a 3.2% ML increase observed.  This approach not only sheds light the direct consequences of nozzle clogging but also deepens the understanding of its broader impact on the continuous casting process.

Presenting Author: Chenn Zhou Purdue University Northwest

Presenting Author Biography: Dr. Chenn Zhou is the founding Director of the Steel Manufacturing Simulation (SMSVC) and Visualization Consortium and the Center for Innovation through Visualization and Simulation (CIVS), NIPSCO Distinguished Professor of Engineering Simulation, Professor of Mechanical Engineering at Purdue University Northwest, and Professor by Courtesy at Purdue University West Lafayette.
Dr. Zhou received her B.S. and M.S. degrees in power engineering from Nanjing University of Aeronautics and Astronautics, China, and a Ph.D. in mechanical engineering from Carnegie Mellon University, USA. She joined Purdue University Northwest in 1994 after three years of industrial experience. Dr. Zhou has more than 37 years of experience in the areas of computational fluid dynamics (CFD), combustion, energy, multiphase reacting flows, and air pollution control. She has been developing state-of-the-art CFD models and applied them to aluminum, glass, refinery, steel, and power industries. She is on the cutting edge in the integration of computer simulation and virtual reality visualization for industrial and educational applications.
Dr. Zhou has conducted a large number of funded research projects totaling over $27 million and collaborated with many experts from over 110 organizations including academia, national laboratories, and industries. Dr. Zhou has published more than 470 technical papers, five copyrighted CFD codes, and two patents. She has received numerous awards including the R&D 100 Award in 2004, the Medal Award by the American Iron and Steel Institute in 2005, the J. Keith Brimacombe Memorial Lecture Award by the Association of Iron and Steel Technology (AIST) in 2010, the 2012 Chanute Prize for Team Innovation, and the Gerald I. Lamkin Fellow Award for Innovation & Service 2017-2018, October 2017. She and her co-authors also received the AIST Josef S. Kapitan Award in 2005, 2016, 2017 and 2021, the AIST Computer Applications Best Paper award in 2006, 2017 and 2021, the 2017 AIST Hunt-Kelly Outstanding Paper Award – First Place, and the 2014 International Thermoelectric Society Outstanding Poster Award, She was named “One of 12 Most Influential over 50” by Northwest Indiana Business Quarterly Magazine in 2014. Dr. Zhou received the awards of Outstanding Faculty in Teaching, Research, and Engagement at Purdue University Northwest. Dr. Zhou has been a Fellow of the American Society of Mechanical Engineers since 2003. In 2020, Dr. Zhou was elected as NIPSCO Distinguished Professor of Engineering Simulation.
Dr. Zhou has been very active in professional societies. She has served as the chair of the Fire and Combustion Committee in the Heat Transfer Division of ASME and the Associate Editor of the Journal of Thermal Engineering and Science. She has chaired international conferences and organized a number of technical sessions for various conferences. She has served as a member of various boards and committees such as the AIST Foundation Board of Trustees.

Authors:

Dianzhi Meng Purdue University Northwest
Sai Bhuvanesh Nandipati Purdue University Northwest
Armin Silaen Purdue University Northwest
Chenn Zhou Purdue University Northwest