Gas Bubble Digital Data Generation by Image Analysis Using Reduced-Scale Water Modeling of a Slab Continuous Caster Mold

Author(s):  
K. Chattopadhyay ◽  
S. Dinda ◽  
J. Sengupta ◽  
A. Srivastava
Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 948
Author(s):  
Changjun Wang ◽  
Zhongqiu Liu ◽  
Baokuan Li

Electromagnetic fields have emerged as powerful tools for addressing current problems in thin slab continuous casting processes in the iron and steel industry. Substantial studies have been undertaken on the fundamental effects of electromagnetic brakes (EMBr) and strand electromagnetic stirring (SEMS). However, little attention has been focused on melt flow and solidification in a thin slab continuous caster with the simultaneous application of an EMBr and SEMS. The present study aimed to predict transient fields in the caster using a large eddy simulation and an enthalpy-porosity method. The electric potential method was applied in the braking process, and the conductivity change with solidification was considered. The suppressive effect on the intensity of the nozzle jet, the balance effect on the mold flow, and a dispersion effect could be observed. The dispersion effect was a novel finding and was beneficial to a flatter nozzle jet. In contrast, SEMS caused a highly turbulent flow in the strand. A large vortex could be observed in the casting direction. The solidified shell became more uniform, and the solidification rate became obviously slower. These findings supported the view that a high-quality thin slab can be produced by the application of an EMBr and SEMS.


2018 ◽  
Vol 21 (2) ◽  
pp. 419-437 ◽  
Author(s):  
Luci Pangrazio ◽  
Neil Selwyn

The capacity to understand and control one’s personal data is now a crucial part of living in contemporary society. In this sense, traditional concerns over supporting the development of ‘digital literacy’ are now being usurped by concerns over citizens’ ‘data literacies’. In contrast to recent data safety and data science approaches, this article argues for a more critical form of ‘personal data literacies’ where digital data are understood as socially situated and context dependent. Drawing on the critical literacies tradition, the article outlines a range of salient socio-technical understandings of personal data generation and processing. Specifically, the article proposes a framework of ‘Personal Data Literacies’ that distinguishes five significant domains: (1) Data Identification, (2) Data Understandings, (3) Data Reflexivity, (4) Data Uses, and (5) Data Tactics. The article concludes by outlining the implications of this framework for future education and research around the area of individuals’ understandings of personal data.


2011 ◽  
Vol 287-290 ◽  
pp. 2768-2771
Author(s):  
Yu Ma ◽  
Jing She Li ◽  
Xiao Chuan Lin ◽  
Li Yuan Sun

The fluid flow in the mould of slab continuous caster was investigated by 1:1 ratio water modeling simulation system. The effects of outlet angle of Bilateral and quadripuntal SEN on surface turbulence, penetration depth and surface velocity were discussed and the regularity of the flow field for change of outlet angle in slab continuous casting mould was obtained. The results show that the case C (both α and β are downward angle and α<β) is better than the usual SEN, for this kind of SEN can stabilize surface turbulence and reduce penetration depth and get moderate velocity.


2021 ◽  
Author(s):  
Prasanta Pal ◽  
Judson Brewer

<div> <div> <div> <p> In the modern world, it is hard to imagine a day without some form of interaction with digital data. Real world data originating from signal generating transducers or communication channels are often recorded as streams of data samples separated by time stamps, sample counters or simply data record delimiter e.g. newline (\n), comma (,) etc. Sampling is the basis of statistical estimation from any data source containing signal records. The process of random sampling has been in practice since time immemorial. However, rapid scale of data generation processes working in tandem with of computing infrastructures , the volume of data is getting quite unmanageably large in nearly every discipline of science. On the other hand, mere volume of data is of no consequence if we can’t extract effective intelligence out of it on an “on demand” basis. Of particular interest is the case where data is stored in a file as a record separated by newline(or any other delimiter) character. When the number of records in the file is greater than a threshold, random sampling is a formidable task. It is nearly impossible to pragmatically load the entire file in the computer memory or even if theoretically possible, the time it takes to load the data in its entirety from natural data sources can be overwhelmingly long or often unnecessary! We can strategically bypass these problems by carefully designing a data interface tool such that any part of a given file can be instantly accessed for random sampling or other kinds of processing tasks by loading only the necessary parts of the data. With this goal, we created a novel, portable and highly efficient rapid data access tool named GSFRS: Giant Signal File Random Sampler, written in modern C++ language to enable near real-time access to any part of an arbitrarily large sized data file that is almost independent of the file size for all practical scenarios. Also, big-data processing would become relatively commonplace and cost effective even in commodity hardwares once the indices are made available through its indexing protocol. This capability would potentially revolutionize the way we gather intelligence from files containing large samples. Adaptation of GSFRS at the source level of various data generators, processing times and energy footprints of various computations can be dramatically reduced. </p> </div> </div> </div>


2020 ◽  
Vol 14 (4) ◽  
pp. 1090-1104
Author(s):  
J. Friess ◽  
U. Sonntag ◽  
I. Steller ◽  
A. Bührig-Polaczek

Abstract Since graphite classification by visual analysis exhibits large variations, a more integrative concept of graphite shape classification is required to evaluate the correlations of process, microstructure and properties, and to fulfill customers’ requirements. The automatic digital image analysis is partly based on visual analysis, but it is not thoroughly defined for graphite shape classification. For example, nodules and thereby nodularity are only defined by the shape parameter roundness, although several studies suggest more sophisticated approaches. Within the first of three successive round robin tests, visual assignment for a variety of graphite particles was performed to obtain a universal digital data set of classified graphite particles. For this, the classification approach from standard EN ISO 945-1 was used and extended with degenerated graphite. The assigned particles were evaluated concerning different shape parameters showing that roundness and the assigned minimum limit value of 0.6 are not sufficient to distinguish nodules from less ideal graphite particle shapes. Furthermore, the current classification approach does not represent the full spectrum of graphite morphologies and needs to be extended. The development of a universal hierarchical classification method for nodules and other graphite shapes has been initiated, and the results will contribute to an improved image analysis standard for ductile iron, particularly ISO 945-4.


2011 ◽  
Vol 130-134 ◽  
pp. 2280-2283
Author(s):  
Yong Ma ◽  
Yu Cheng Wu ◽  
Wen Lin Chen ◽  
Xin Fang Wang ◽  
Ya Pei Zhao

The stability of mold oscillation can directly influence on slab surface quality and operational safety in continuous casting. In recent years, the hydraulic oscillation is developed and applied as the driven equipment of mold oscillation. In the present work, based on the slab continuous caster of hydraulic oscillations, the displacement and other parameters of hydraulic oscillator are measured and the evaluation method of oscillation is studied. The displacement difference and phase difference of oscillation with sinusoidal waveform and non-sinusoidal waveform are analyzed. Especially, the dynamic characteristics of the driving force of left and right cylinders are evaluated. The results indicated that the hydraulic oscillator is quite a good device in terms of precision. The method proposed may be useful for evaluating oscillators.


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