Acoustical Performance of Lined Induction Furnace in Electric Field Configuration
Date of Award
Ph.D. in Mechanical and Aerospace Engineering
Department of Mechanical and Aerospace Engineering
Aluminum is widely used in the aerospace, transportation, and electronic industries due to its high thermal conductivity, excellent corrosion resistance, good casting performance, and reasonable cost. Aluminum can absorb dissolved hydrogen gas during the melting processing which leads to porosity after solidification. Therefore, removing dissolved hydrogen gas from aluminum melt (degassing) is necessary for increasing material quality. In some material processing applications, time-dependent electromagnetic forces may influence the surface shape, nucleation of precipitates, segregation of alloy components, gain refinement, and degassing. Degassing can occur in an induction furnace due to acoustic wave propagation. The purpose of this study is to explore the potential for using an electromagnetic field for degassing a liquid metal in a cylindrical induction furnace. In this study, a continuum-based model is developed to represent a commercial size induction furnace. This model can be used to identify a favorable set of operating conditions so that electromagnetically-induced degassing can be used to remove dissolved gas from the liquid aluminum within the furnace. The presence of the crucible liner within the furnace is taken into account in this work as the presence of the crucible liner has the potential to affect the vibrations within the melt. Shell theory is used in conjunction with acoustic theory to create a model that treats the interactions between the crucible liner and the liquid melt. Eigenfrequencies and vibration modes are calculated with different boundary conditions (sound hard wall, sound soft wall, and sound semi-soft wall). A set of operating conditions is identified which would promote optimal degassing for an aluminum alloy in a representative commercial furnace.
Mechanical Engineering, Acoustics, degassing, acoustic resonant frequency
Copyright 2021, author
Shi, Yinghui, "Acoustical Performance of Lined Induction Furnace in Electric Field Configuration" (2021). Graduate Theses and Dissertations. 7021.