Numerical Investigation of Fluid Flow and Heat Transfer Phenomenon Inside a Single Strand Tundish of Slab Caster Anurag Tripathi,  Anil Kumar, Satish Kumar Ajmani, J. B. Singh, and Vinay V. Mahashabde The tundish design is an important factor which governs the steel quality. An effective tundish design can enhance inclusion flotation through development of required liquid steel flow pattern. The well-shaped bottom is one of the developments in the area of tundish design. This tundish is in practice and has significantly contributed towards improving the productivity of the steel plants. The current work investigates the liquid steel flow phenomenon in this type of tundish. The 3D CFD model was used for present investigation. The results obtained shows that well-shaped bottom tundish produces better performance as compared to tundishes having flat bottom. The effect of bath height, throughput and depth of well on flow behavior inside the tundish having well-shaped bottom was studied in the current work. The results of RTD analysis show the need to optimize these parameters. CFD simulations were also performed to capture the non isothermal phenomenon in a well-shaped bottom tundish. 1. Introduction The increase in productivity without affecting the quality is a major challenge among the steel makers. The separation of inclusion from molten steel is required to achieve the superior quality of steel. The tundish is a steel refining metallurgical vessel used as a buffer during continuous casting. The liquid steel flow phenomenon in a tundish governs the inclusion flotation charecter- istics. RTD (Residence time distribution) characteristic is an established criterion for predicting the inclusion separation in the tundish. Ahuja and Sahai [1] have postulated that surface directed flow enhances the inclusion separation ratio. It is expected that flow without hindrances facilitate the inclusion flotation. Plug volume in RTD analysis represents the hindrances free flow region of the tundish. Estimation of dead volume in RTD analysis gives the percentage of unutilized volume of the tundish. Inclusion trapped in dead volume can not float out. There are various studies reported in the literature about the effect of operating parameters on inclusion separation characteristics. [2–4] The increase in production results in an enhanced throughput for tundish. Here, throughput means rate at which the liquid steel flows out of the tundish. Throughput in steel plant is generally measured in tonnes/minute (tpm). Hence, increase in throughput leads to a loss of residence time for fluid elements inside the tundish. The bath height of liquid steel in the tundish can drop below optimum level during ladle change over operation, due to rise in throughput. The change in throughput can also affect the fluid flow characteristics of tundish. Thus, metallurgical and refrac- tory performance of tundish can detoriate with increase in productivity. The increase in volume of tundish is required to compensate the loss in residence time. The volume increase can either be incorporated through change in shape or dimensions of tundish. Investigators have reported various studies on fluid flow behavior using physical and mathematical modeling in a tundish. [5–9] They came up with the various designs of tundish, such as rectangular tundish, tundish with sloping sides, curved shape tundish, wedge shaped tundish, etc. The well-shaped bottom is another innovation in the area of tundish design. It is being used, successfully, by the steelmakers around the world. However, the different aspects of this tundish design are still unexplored in the research community. The merits of the well-shaped bottom design and its effectiveness at higher throughput is still an area of research among steel making commun- ity. [10–12] The investigations were performed in the present work to understand the flow phenomenon in this type of tundish. Its comparative analysis was performed with [  ] A. Tripathi, A. Kumar, S. K. Ajmani, J. B. Singh, V. V. Mahashabde Research and Development, Tata Steel, Jamshedpur 831001, India Email: anurag.tripathi@tatasteel.com DOI: 10.1002/srin.201400530 www.steel-research.de 1558 steel research int. 86 (2015) No. 12 ß 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim FULL PAPER