Flow fields in electromagnetic stirring of rectangular strands with linear inductors: Part II. computation of flow fields in billets, blooms, and slabs of steel

The model presented in Part I of this series of papers is used to compute flow velocities in the longitudinal stirring of steel blooms and billets, and in the horizontal stirring of steel slabs. In longitudinal stirring of blooms and billets the reverse flow is on the side of the strand opposite to the inductor. The effects of penetration depth of the electromagnetic force, of the force itself, of the length of the stirrer, and of the width of the liquid core were determined. In horizontal stirring of slabs the reverse flow takes place outside of the stirrer region, forming the so-called butterfly stirring pattern. The characteristics of this flow field depend to a considerable extent on the width of the stirrer. The effects of stirrer width, of thickness of the liquid core, of force and of width of the slab were elucidated. The maximum velocities in both types of stirring are represented as simple formulae. Formerly with Institut für Allgemeine Metallurgie, Technische Universit?t Clausthal     

Rotational electromagnetic stirring in continuous casting of round strands

A model is presented to compute the three-dimensional flow field in rotational electromagnetic stirring of round strands. The model involves the solution of the Maxwell equations, the Navier-Stokes equations, and the transport equations for the turbulence characteristicsk andε. For the limiting case of one-dimensional stirring, the computations were checked with experiments using mercury as the fluid. Several sets of computations were carried out to determine the influence of stirrer position, stirrer length, and electromagnetic parameters on the flow field in continuous casting of steel strands.     

Precise conversion electron intensities of Eu decay for detector calibration purposes

A double focusing electron spectrometer has been used to determine precise relative intensities of internal conversion electron (ICE) lines following the decay of ¹⁵²Eu in order to produce a suitable standard for solid state electron detectors. Intensities of 21 electron lines are given in the energy range 198 keV to 1.361 MeV with a precision close to 3.5%. For the 0₂⁺−0₁⁺ E0 transition in ¹⁵²Gd, a precise energy of 615.406(11) keV has been established and an X-value of 0.047(5) was derived.     

Microtox Toxicity Test Results for Water Samples from the Detroit River

The toxicities of over 70 water samples from the Detroit River between Lake St. Clair and the western basin of Lake Erie to the bioluminescent Photobacterium phosphoreum were determined with the Microtox toxicity analyzer. The samples were analyzed in the field within a few hours of collection and again several weeks later in the laboratory. After the storage, the samples were fractionated by distillation under vacuum. This process yielded three fractions of each sample of which the first fraction, enriched in some of the volatile contaminants, and the third fraction, containing the non-volatile compounds, were analyzed. High toxicities were found for several of the original samples and also for the first and third fractions of some concentrated samples. Testing of samples with this system provided a general overview of acute toxicity and may be useful for the quick recognition of contamination hotspots.