TY - GEN
T1 - Methodology of water modeling and submerged-entry nozzle (SEN) design for bloom casting with mold electromagnetic stirring (MEMS)
AU - Brighton, A.
AU - Glaws, P. C.
AU - Valentine, N. M.
AU - Dorricott, J. D.
AU - Heaslip, L. J.
AU - Morales, R. D.
AU - Chalmers, D. J.
PY - 2014
Y1 - 2014
N2 - A water modeling methodology for the simulation of bloom casting with mold electromagnetic stirring (MEMS), which involves the incorporation of a rotary mechanical stirrer within the model mold, has been developed and implemented. The influence of SEN design was examined and the effects of two SEN designs, a 2-port and a 4-port nozzle, were compared in two bloom molds (a small and a big mold of differing aspect ratios) over a range of casting speeds, stirring intensities, and SEN port submergence depths. A method of video frame image analysis, which involved the determination and discrimination of the change in RGB color intensity of pixels after the injection of dye, was used to determine the rise time of the flow to the sub-meniscus regions. Rise times were found to be longer in the big mold than in the small mold, and to be increased by an increase in SEN port submergence, as well as to be even more substantially increased when mold stirring was used. The 2-port and 4-port SEN designs tested showed only minor differences in rise times over the range of operating conditions considered. The observance of mold level fluctuation in the water model indicated that this was principally caused by travelling waves on the pool surface generated by the occasional release of large (>5mm dia.) gas bubbles from the upper portion of the SEN ports and the subsequent bursting of these bubbles when they reach the surface of the liquid pool. Mold stirring was found to be a principal influence in the reduction of mold level disturbances induced by the gas bubbling. Detailed examinations were carried-out using an ultrasonic level sensor positioned to sense changes in mold level near a mold corner. These examinations found a consistent increase in mold level fluctuation, as indicated by increased mold level standard deviation, with increased gas injection rates from 0 to 5 LPM. In conclusion, it has been found that by using the water modeling methodology described in this study, a reasonable insight can be developed into the influence of MEMS on the mold flow behavior in bloom casting, and into the interactions between SEN design, casting conditions and mold stirring intensity.
AB - A water modeling methodology for the simulation of bloom casting with mold electromagnetic stirring (MEMS), which involves the incorporation of a rotary mechanical stirrer within the model mold, has been developed and implemented. The influence of SEN design was examined and the effects of two SEN designs, a 2-port and a 4-port nozzle, were compared in two bloom molds (a small and a big mold of differing aspect ratios) over a range of casting speeds, stirring intensities, and SEN port submergence depths. A method of video frame image analysis, which involved the determination and discrimination of the change in RGB color intensity of pixels after the injection of dye, was used to determine the rise time of the flow to the sub-meniscus regions. Rise times were found to be longer in the big mold than in the small mold, and to be increased by an increase in SEN port submergence, as well as to be even more substantially increased when mold stirring was used. The 2-port and 4-port SEN designs tested showed only minor differences in rise times over the range of operating conditions considered. The observance of mold level fluctuation in the water model indicated that this was principally caused by travelling waves on the pool surface generated by the occasional release of large (>5mm dia.) gas bubbles from the upper portion of the SEN ports and the subsequent bursting of these bubbles when they reach the surface of the liquid pool. Mold stirring was found to be a principal influence in the reduction of mold level disturbances induced by the gas bubbling. Detailed examinations were carried-out using an ultrasonic level sensor positioned to sense changes in mold level near a mold corner. These examinations found a consistent increase in mold level fluctuation, as indicated by increased mold level standard deviation, with increased gas injection rates from 0 to 5 LPM. In conclusion, it has been found that by using the water modeling methodology described in this study, a reasonable insight can be developed into the influence of MEMS on the mold flow behavior in bloom casting, and into the interactions between SEN design, casting conditions and mold stirring intensity.
UR - http://www.scopus.com/inward/record.url?scp=84905869876&partnerID=8YFLogxK
M3 - Contribución a la conferencia
AN - SCOPUS:84905869876
SN - 9781935117421
T3 - AISTech - Iron and Steel Technology Conference Proceedings
SP - 1727
EP - 1735
BT - AISTech 2014 - Proceedings of the Iron and Steel Technology Conference
PB - Association for Iron and Steel Technology, AISTECH
T2 - AISTech 2014 Iron and Steel Technology Conference
Y2 - 5 May 2014 through 8 May 2014
ER -