scholarly journals Physical modeling of bubble phenomena, electrolyte flow and mass transfer in simulated advanced Hall cells

1990 ◽  
Author(s):  
J Evans ◽  
R Shekhar
2019 ◽  
Vol 842 ◽  
pp. 203-213 ◽  
Author(s):  
M. Huang ◽  
G. Marinaro ◽  
X. Yang ◽  
B. Fritzsche ◽  
Z. Lei ◽  
...  

1963 ◽  
Vol 85 (4) ◽  
pp. 395-401 ◽  
Author(s):  
Reno R. Cole ◽  
Yoram Hopenfeld

A method of polishing metals by means of an electrolytic jet at extremely high current densities (to 1750 amps per sq in.) is described. Data are presented on the relation of polishing effect on various metals to current density and electrolyte flow rate for several electrolytes. An experimental method is described whereby the relationship of the above factors can be determined. It was found that all metals investigated could be polished at high enough current densities. Previous theories of electrolytic polishing are discussed and shown to not fully account for the process investigated. A modified theory to account for polishing at the high current densities observed is presented and is supported by mathematical analysis based on fundamental mass transfer considerations.


Author(s):  
V.P. Piptyuk ◽  
P.G. Prokopenko ◽  
S.V. Grekov ◽  
G.O. Andrievsky

The purpose of the work is to determine the effect of slag on the processes of mixing the steel melt in the ladle during its bottom purge. The study by physical modeling was carried out on a transparent bucket model with its bottom purge without slag layer and, if any, it was present. Water was used as the liquid of the metal, and slag was sunflower oil. The bath was washed with air at various costs. Controled the thickness of the slag layer and the surface area of the metal surface from it. The level of conductivity of a water bath was determined depending on the variables. A slight decrease in the electrical conductivity of the melt mist (water) in the presence of slag is observed, as well as an increase in the thickness of the slag layer and the surface area of the melt surface with increasing air flow. The factors which can be applied for the calculation of hydrodynamic processes during the processing of steel on the "ladle-furnace" installation, taking into account the slag component, are revealed. It is shown that when the air flow increases, the diameter of the water released from the slag (oil) increases, and when the volume of the latter is stored, the thickness of its layer increases. The expediency of continuation of researches by cold physical modeling of hydrodynamics, heat and mass transfer with and without slag is shown, which will allow them to be taken into account in hot modeling and in industrial conditions.


Author(s):  
J A McGeough ◽  
J R Thomson

Iron foil of approximate thickness 0.05 mm has been electroformed from an electrolyte solution, composed mainly of ferrous chloride and flowing at Reynolds numbers ranging from 1620 to 19 400. Current densities between 15 and 45 A/dm2 have been used. At low Reynolds numbers, the current efficiency for metal deposition is limited by inadequate mass transfer. As the Reynolds number is increased, the current efficiency rises to a maximum, after which the efficiency is again reduced due to excessive occurrence of a reaction involving the reduction of ferrous hydroxide to iron. The Young modulus of the material along the direction of electrolyte flow is less than the recognized value for polycrystalline iron and steel. This is because of the crystal orientation and internal stresses of the electrodeposited metal. Electrolyte flow induces hydrogen embrittlement of the foil. This condition is found to exert a greater influence than grain size on tensile strength, ductility and proof stress. Its effects can be alleviated by stress relief. The hardness is unaffected by hydrogen embrittlement, but is increased at higher Reynolds numbers, due to the formation of smaller grains. Direct heating of the cathode reduces material hardness without affecting tensile properties. The introduction of electrolyte flow raises the rate of electroforming of iron only by about 50 per cent when compared with that obtained from an unstirred electrolyte. This surprisingly small effect of flow is attributed to the slowness of the chemical reactions which have more control over the rate of deposition of iron than the rate of mass transfer.


Sign in / Sign up

Export Citation Format

Share Document