Computer Simulation of Induction Heating Processes Dr. Valentin Nemkov Mr. Robert Goldstein Centre for Induction Technology, Inc. Auburn Hills, MI USA
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Computer Simulation of
Induction Heating Processes
Dr. Valentin Nemkov
Mr. Robert Goldstein
Centre for Induction Technology, Inc.
Auburn Hills, MI USA
Overview
• Benefits of Computer Simulation
• Special Features of Induction Heating
Computer Simulation
• Induction Heating Computer Simulation
Software
• Rule of Pyramid
• Computer Simulation Example
Computer Simulation Rules of Thumb
• Works for Any
Geometry and
Conditions
• Demonstrate the
Entire Dynamics of
the Process
• Leaves a Record for
Future Study
• Limitless Accuracy
• Good for Simple
Geometries
• Don’t Provide a Good
Understanding of the
Process
• Experience Isn’t
Passed On
• Case Dependent
Accuracy
Accuracy of Computer
Simulation
• Mainly Depends upon Description of
Material Properties
• Number, Distribution and Type of Elements
• System Description
Why Isn’t there One Comprehensive
Computer Simulation Software Package for
Induction Heating?
• Induction heating simulation involves a set of mutually
coupled non-linear phenomena
• Many induction applications are unique and may require
individual program structures
• Powerful personal computers with high processing speeds
and large available memory only recently became available
• The induction heating market is small compared to other
industrial sectors
• It is difficult to make an induction coil that doesn’t heat at
all and some users don’t care about design optimization
Process Control
Machine Operating Mode Power Supply Circuits
Thermal Process (Heating) Electromagnetic Process
Cooling Quenching Stresses
Structural Transformations Distortions
Specific Features of Induction Heating
Computer Simulation
Types of Programs for Induction Heating
Computer Simulation at CIT
PC simulation programs
Type Example
1D coupled Elta
2D Electromagnetic QuickField
2D Thermal Flux2D
2D Coupled Flux2D
3D Electromagnetic Flux3D
3D Thermal Flux3D
ELTA, 1-D Software Features
• User Friendly Interface with Very Fast
Solver
• Electromagnetic + Thermal
• Axisymmetrical or Plane Parallel
Geometries
• Database with Non-Linear Properties of
Materials
• Automatic Report Generation
Scanning Simulation Using
ELTA
QuickField, 2-D Software
Features
• User Friendly Interface
• Electromagnetic Only
• Linear Materials Only
• Fast Solver
• Inexpensive
Flux 2D, Software Features
• Less Friendly User Interface
• Electromagnetic + Thermal
• Material Database with Non-Linear
Properties
• Can Work in Conjunction with Other
Software (AutoCad, MatLab, etc.)
Flux 3D, Software Features
• Less Friendly User Interface
• Electromagnetic or Thermal
• Material Database with Non-Linear
Properties
• Tetrahedral, Cubic and Prizmatic Elements
3-D Simulation of Heat
Exchanger Joint Brazing
Rule of Pyramid
3D
2D, Electromagnetic or Thermal
1D, Electromagnetic + Thermal
2D, Electromagnetic +
Thermal
Computer Simulation of Seam
Annealing Process
Induction Seam Annealing
• Removes Stresses and Improves
Microstructure after Induction Seam
Welding
• High Production Rates, > 3 ft / s
• One of Two Induction Coil Styles Used:
Split-n-Return Vertical Loop
• No Published Studies on Coil Style
Selection
Case Study Conditions
• Tube: 1040 Steel
– 2” Diameter with 1/8” Wall
• Frequency 10 kHz
• Same Current Applied (2200 A)
• Production Rate 3.8 ft / s
• Flux Concentrator: Fluxtrol A
Half of Geometry Used For
Simulation, 2mm Grid
Vertical Loop Split-n-Return
Vertical Loop Inductors
Magnetic Field Lines
Return Leg Same Tube Return Leg Wider Tube
Vertical Loop Inductors, Final
Temperature Distribution
Return Leg Same Tube
Tmax 934 C Tmax 938 C
Return Leg Wider Tube
Vertical Loop Inductors, Flux
Density in the Concentrator
Return Leg Same Tube
Return Leg Wider Tube
Split-n-Return Inductor Magnetic
Field Lines
Split-n-Return Inductor Final
Temperature Distribution
Tmax 959 C
Split-n-Return Inductor, Magnetic
Flux Density in Concentrator
Table of Results of Simulation
Style Coil V Coil I Coil Loss Tube P Max T Efficiency Total Power
VL Same 378 2200 36.0 216 934 85.7% 252
VL Wide 321 2200 31.8 216 938 87.0% 248
SNR 272 2200 31.1 236 959 88.0% 267
Results of Study on Seam
Annealing
• Both Induction Coil Styles When Properly
Designed Work Effectively for the Seam
Annealing Process
• For Vertical Loop Inductors, a Wider
Return Leg Should Be Used
• Computer Simulation Is an Effective Tool
for Prediction and Study of Induction Seam
Annealing System Performance
Conclusions
• There are Many Advantages of Using
Computer Simulation
• The Specific Features of an Induction
Heating System must be Considered for
Computer Simulation
• The Rule of Pyramid is a Strategy for
Limiting the Time Required for Simulation
Related Documents
