1. S. Mandayam/ NDE/ Fall 99 Principles of Nondestructive Evaluation Shreekanth Mandayam Graduate / Senior Elective 0909-504-01/0909-413-01 Fall 1999 http://engineering.rowan.edu/~shreek/fall99/nde/ Lecture 2 9/20/99

2. S. Mandayam/ NDE/ Fall 99Plan Electromagnetic NDE methods Problem statement Maxwell’s equations Governing equations Static Quasi-static Wave Selection of class projects Open discussion 9/20/99

3. S. Mandayam/ NDE/ Fall 99 Problem Statement Amplitude, a Frequency, f Coupling device, c Specimen geometry, g Specimen material distribution, p Defect geometry, d Measurement system, m Energy input, x = F 1 (a, f) Signal output, y = F 2 (a, f, c, g, p, d, m)

4. S. Mandayam/ NDE/ Fall 99 Maxwell’s Equations

5. S. Mandayam/ NDE/ Fall 99 Maxwell’s Equations

6. S. Mandayam/ NDE/ Fall 99 Maxwell’s Equations

7. S. Mandayam/ NDE/ Fall 99 Constitutive Relationships

8. S. Mandayam/ NDE/ Fall 99 Electromagnetic NDE Methods

9. S. Mandayam/ NDE/ Fall 99 Static Phenomena: DC Potential Drop Elliptic partial differential equation

10. S. Mandayam/ NDE/ Fall 99 Static Phenomena: Magnetic Flux Leakage

11. S. Mandayam/ NDE/ Fall 99 Static Phenomena: MFL (contd.) Elliptic partial differential equation

12. S. Mandayam/ NDE/ Fall 99 Quasi-static Phenomena

13. S. Mandayam/ NDE/ Fall 99 Quasi-static Phenomena

14. S. Mandayam/ NDE/ Fall 99 Quasi-static Phenomena (contd.) Parabolic partial differential equation

15. S. Mandayam/ NDE/ Fall 99 Wave Phenomena

16. S. Mandayam/ NDE/ Fall 99 Wave Phenomena (contd.) Hyperbolic partial differential equation

17. S. Mandayam/ NDE/ Fall 99Reference William Lord, “Partial differential equations and the NDE inverse problem,” Review of Progress in Quantitative Nondestructive Evaluation, Vol. 7, pp. 425-430, 1988

18. S. Mandayam/ NDE/ Fall 99 NDE Processes Elliptic Processes Parabolic Processes Hyperbolic Processes HIGH LOW HIGH Forward Problem Difficulty Inverse Problem Difficulty Informational Entropy

19. S. Mandayam/ NDE/ Fall 99 Class Projects 1. Ultrasound NDE: Neural nets for signal interpretation 2. Ultrasound NDE: Invariant signal recognition 3. Eddy current NDE: Simulating eddy current inspection of VLSI chips (proposal to NSF)

20. S. Mandayam/ NDE/ Fall 99 Class Projects 4. Eddy current NDE: Design and develop an eddy current instrument (measure amplitude and phase of voltage using commercial eddy current probes) 5. Microwave NDE: System set up and experimentation for detecting frayed insulation in aircraft wiring

21. S. Mandayam/ NDE/ Fall 99 Class Projects 6. Thermal NDE: Set up system to perform thermal imaging 7. Parallel Processing & Monte Carlo Modeling: Develop software for solving NDE forward problems using Monte Carlo techniques 8. Magnetic Flux Leakage NDE: Neural networks for invariant recognition

22. S. Mandayam/ NDE/ Fall 99 Class Projects 9.--- Student specified projects: Check with instructor

23. S. Mandayam/ NDE/ Fall 99 Proposal Format Background Research Objective Proposed Methodology Deliverables Project timeline Please come prepared to present a project proposal for the next class meeting (Sep 27).