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1 – 2 of 2Valdis Bojarevics and Koulis Pericleous
The purpose of this paper is to investigate a new type of nozzle which is free from erosion and non-contaminating the outflow metal. Cold crucible melting technique with…
Abstract
Purpose
The purpose of this paper is to investigate a new type of nozzle which is free from erosion and non-contaminating the outflow metal. Cold crucible melting technique with electromagnetic induction is used to obtain reactive metal castings and produce high-quality metal powders for aerospace, automotive and medical applications. An important part of this technology is the nozzle used to pour the molten alloy through the bottom opening.
Design/methodology/approach
The paper uses mathematical modeling technique, previously validated on multiple similar cases, to investigate a new type of nonconsumable nozzle made of copper segments.
Findings
The design of the nozzle requires to satisfy the narrow balance between the thin solidified protective layer on the wall while avoiding the blockage of the outflow if the nozzle is frozen completely. The sensitivity of the outflow to the nozzle diameter is investigated. The AC electromagnetic force leads to high mixing rates, transitional flow structures and turbulence of the melt, contributing to the melt shape dynamics and the heat loss to walls.
Originality/value
The beneficial features of the cold crucible melting to purify the melt from particulate contamination are explained using the full melting and pouring cycle.
Details
Keywords
Valdis Bojarevics, Alan Roy and Koulis Pericleous
The purpose of this paper is to create a numerical model of electrode induction melting process for the gas atomization (EIGA) and process and investigate the complex interaction…
Abstract
Purpose
The purpose of this paper is to create a numerical model of electrode induction melting process for the gas atomization (EIGA) and process and investigate the complex interaction of the electromagnetic and thermal fields on the fluid flow with free surface.
Design/methodology/approach
The modelling approach is based on the free surface code SPHINX which includes time dependent electromagnetic, thermal and fluid flow with free surface modelling and the commercial software COMSOL for investigating 3D electromagnetic effects.
Findings
The melting dynamics, liquid film formation and the outflow free surface behavior are predicted by SPHINX using an optimized geometry. Quasi‐stationary AC electromagnetic solutions with COMSOL predict some 3D effects of the coil, including frequency dependent estimates of voltage, electric current and power.
Originality/value
The importance of magnetic forces controlling the free surface jet formation, partial semi‐levitation and the outflow superheat is uncovered by numerical modelling tools. An optimized geometry is presented for the EIGA process.
Details