Mihails Ščepanskis

The Numerical Model of Electrothermal Deformations of Carbides in Bearing Steel as the Possible Cause of White Etching Cracks Initiation

Despite the ongoing debates on influence of hydrogen uptake and penetration in the steel, pulsed and extraordinary fatigue on white etching cracks (WEC) formation in bearing steel SAE52100, the present paper proposes an alternative hypothesis on electrothermal initiation of the WEC. The hypothesis points to differences between electrical and thermal properties of elements of steel microstructure that lead sequentially to redistribution of current, resistivity heating, thermal expansion and deformations of the carbide particle. Appearance of a nano-void is also predicted by the model in the cases of the martensite and the bainite structures. The model also predicts higher probability of the WEC formation for the bainitic steel.

Statistical analysis of the influence of forces on particles in EM driven recirculated turbulent flows

The present paper contains an analysis of the statistical distribution of forces affecting non-conducting particles dispersed in an EM induced recirculated flow in induction furnaces. The simulation is conducted adopting the LES-based Euler-Lagrange approach in the limit of dilute conditions (one-way coupling). It is done by means of a development of OpenFOAM software code. The used Lagrange equation for particle tracking includes drag, EM, buoyancy, lift, acceleration and added mass forces. The relevant approximations for the forces are chosen on the basis of the statistical analysis of the non-dimensional parameters (particle Reynolds number, shear stress and acceleration parameter). The effect of force distribution on particle homogenization is described under different density ratios and particle sizes. The recommendations of the consistence of the Lagrange model for the simulation of the particle motion in the laboratory scale induction crucible furnace are given in conclusion.

Molten Salts Cannot be Used for the Study of Turbulent Electromagnetically Driven Flows of Liquid Metal

Abstract This paper presents the analysis of the possibility to use molten salt as a physical model of liquid metal for experimental study of turbulent electromagnetically driven flows. The conclusion is—the molten salt is not suitable for this goal. The conclusion is done based on the results on numerical simulation.