Inclusion behavior in an Aluminum bath stirred by induction

Abstract : With an objective of improving processing and development of aerospace aluminum alloys, the current dissertation presents experimental and numerical tools which help comprehend the behavior of a non-metallic inclusion population in an Al bath stirred by induction. The mechanisms occurring in the metallurgical reactor were separated into two interlinked issues – (i) Magnetohydrodynamics (MHD) of the induction furnace, and (ii) Inclusion population dynamics in the Al bath, which were modeled using the ANSYS Fluent software and in-house User Defined Functions. For a 2D axisymmetric geometry, numerical simulations were performed in a single framework and calculated: (i) the electromagnetic forces using the A-V formulation, (ii) the free surface deformation using the Volume Of Fluid method, (iii) the turbulent stirring of the bath using a RANS-based k-omega model and (iv) the friction force due to the oxide layer by imposing a pseudo-wall condition on the bath free surface. The steady state MHD results and the physical properties of the inclusion population were used as input data for the transient inclusion behavior modeling. A combination of the Drift Concentration Method and the Population Balance Method was developed to respectively model the mean transport of inclusions within the bath at the macroscopic scale and the inclusion interactions (turbulent aggregation and fragmentation) at the mesoscopic scale. The performance of the MHD numerical tool was evaluated by comparing the model results with experimental results at laboratory and industrial scales. The simulation results in the form of the average bath surface profile were found to be consistent with the laboratory measurements. The results also illustrated the impact of the friction due to the oxide layer on the bath surface deformation as well as on the flow near the dome interface. The inclusion behavior simulations were performed for the holding mode operation of an industrial IMF. The deduced removal frequency compared the relative importance of each phenomenon. It was found that the electromagnetic migration, especially in the electromagnetic skin, dominates the inclusion dynamics and is responsible for the capture of a large fraction of the inclusion population.
Document type :
Theses
File URL :
.
Complete list of metadatas

https://hal.univ-lorraine.fr/tel-01752360
Contributor : Thèses Ul <>
Submitted on : Thursday, March 29, 2018 - 1:43:13 PM
Last modification on : Tuesday, August 21, 2018 - 9:46:04 AM

Identifiers

  • HAL Id : tel-01752360, version 1

Citation

Akshay Bansal. Inclusion behavior in an Aluminum bath stirred by induction. Other. Université de Lorraine, 2016. English. ⟨NNT : 2016LORR0090⟩. ⟨tel-01752360⟩

Share

Metrics

Record views

25