Engineering Electromagnetics 1 0909.301.01 Fall 2004

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Engineering Electromagnetics 10909.301.01 Fall
2004
Lecture 7bOctober 20, 2004

• Shreekanth Mandayam
• ECE Department
• Rowan University
• http//engineering.rowan.edu/shreek/fall04/eemag1
  /

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Plan

• Magnetostatics
• Recall Governing Equations
• Magnetic Force
• B-H Curve
• Quasistatics
• Governing PDE
• Skin depth
• EMI demo
• Course Review
• Instructor Course Evaluation

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EEMAG-1 Topics Today
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Recall Magnetostatics Governing Equations
Recall Field due to a line current
dl
Is
f
ds
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Poissons Equation
Vector Poissons Equation
Scalar Laplacian
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Analogy
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Lorentz Force Law
Force N
Magnetic Flux Density T
Velocity m s-1
Electric Field V m-1
Charge C
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Motion of a Charge in a Uniform Magnetostatic
Field
Let
DEMOmotionbstat
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The B-H Curve
B in T
Br
Hc
H in A m-1
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Electromagnetic Phenomena
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Governing PDE
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Governing PDE (contd.)
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Governing PDE (contd.)
Parabolic partial differential equation
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Skin Depth

• Skin depth (standard depth of penetration), d
  depth at which the current density is 1/e or
  36.8 of surface value
• Effective depth of penetration 3 d

DEMOskineffect.m houseemiac.m
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Skin Depth (contd.)
D. E. Bray and R. K. Stanley, Nondestructive
Evaluation A Tool in Design, Manufacturing and
Service, CRC Press, New York, 1997
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Skin Depth (contd.)
D. E. Bray and R. K. Stanley, Nondestructive
Evaluation A Tool in Design, Manufacturing and
Service, CRC Press, New York, 1997
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EEMAG-1 Course Objectives

• Given a contemporary stastic/quasistatic
  electromagnetic device/system, the student
  should be able to
• Write down the Maxwells equations that describe
  this device/system
• Solve these equations for simple geometries using
  analytical techniques
• Solve these equations for complex geometries
  using MATLAB

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EEMAG-1 Topics
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Summary