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Thermoelastic and Photoelastic Full-Field Stress Measurement W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 1999 Thermoelastic and photoelastic full-field stress measurement Deonna Faye Woolard College of William & Mary - Arts & Sciences Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Condensed Matter Physics Commons, and the Electromagnetics and Photonics Commons Recommended Citation Woolard, Deonna Faye, "Thermoelastic and photoelastic full-field stress measurement" (1999). Dissertations, Theses, and Masters Projects. Paper 1539623969. https://dx.doi.org/doi:10.21220/s2-x5mm-jq08 This Dissertation is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, som e thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9’ black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. Bell & Howell Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with with permission permission of the of copyright the copyright owner. owner.Further reproductionFurther reproduction prohibited without prohibited permission. without permission. THERMOELASTIC AND PHOTOELASTIC FULL-FIELD STRESS MEASUREMENT A Dissertation Presented to The Faculty of the Department of Physics The College of William & Mary in Virginia In Partial Fulfillment Of the Requirements for the Degree of Doctor of Philosophy By Deonna Faye Woolard 1999 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number 9975024 ____ __<g> UMI UMI Microform9975024 Copyright 2000 by Bell & Howell Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. Bell & Howell Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPROVAL SHEET This dissertation is submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Uioolcud Deonna Faye Woolard Approved, July 1999 -XA7M — Mark Hinders (Advisor) L- • Gina Hoatson r r y jte k.r David Armstrong ApiwrRfcflly^A P A f H i i / . /* A William P. Win free (NASA) 11 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Table of Contents Acknowledgments ............................................................................................................................v List of Tables ....................................................................................................................................vi List of Figures ................................................................................................................................ vii A b s tra c t .............................................................................................................................................xi Chapter 1 Introduction ................................................................................................................ 2 1.1 History of Photoelasticity ..........................................................................................2 1.2 History of Thermoelasticity .....................................................................................22 1.1.1 Design of the Polariscope ................................................................................ 5 1.1.2 Advances in Photoelastic Analysis ............................................................... 10 1.3 Motivation to Combine Thermo- and Photoelasticity ........................................32 1.4 Dissertation overview ...............................................................................................34 Chapter 2 Photo-Thermoelastic Coating .............................................................................. 35 2.1 Measurement Systems Overview ............................................................................35 2.2 Coating Characteristics ............................................................................................ 38 2.3 Dual-Use Coating ....................................................................................................... 43 2.4 Reflective Backing ..................................................................................................... 48 C h ap ter 3 Photoelastic Theories...............................................................................................54 3.1 One-Dimensional Theory ......................................................................................... 54 iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 3.2 Modem Optics .......................................................................................................... 58 3.3 Electromagnetic Wave Theory ................................................................................62 3.4 Electromagnetic Wave Theory ................................................................................62 Chapter 4 Anisotropic Electromagnetic Boundary Value Problem........................... 68 4.1 Isoclinic M odel ........................................................................................................ 68 4.2 Ischromatic Model ....................................................................................................76 4.3 Experimental Versus Theoretical Comparison ..................................................... 80 4.4 Combining Thermoelasticity and Photoelasticity .............................................. 91 Chapter 5 Depolarization of Electromagnetic Waves...................................................100 5.1 The Rayleigh C riterion ......................................................................................... 101 5.2 Optical Analysis of the Reflective Backings ......................................................102 5.3 Depolarization by Scattering from Random Rough Surfaces .........................106 5.3.1 Depolarization of Isoclinic Fringes ............... 113 5.3.2 Depolarization of Isochromatic Fringes ................................................... 123 Chapter 6 Summary and Future Direction................................................................... 128 Appendix A Fresnel’s Equation.......................................................................................133 Appendix B Definition of Roughness.............................................................................. 136 Appendix C Derivation of the Thermoelastic Equation.............................................. 140 Bibliography.........................................................................................................................145 Vita..........................................................................................................................................154 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Acknowledgments I would like to express my appreciation to Mark Hinders for his guidance, insight, and enthusiasm for this project. Our collaboration has allowed me to grow intellectually as well as professionally. I would also like to thank the members of my committee for their comments on this document. I am also indebted to Elliott Cramer, Mike Seale, Dan Perey, and Patty Howell of the NASA Langley Research Center in Hampton, Virginia. Your assistance to this project was invaluable. I wish to express my thanks to the Physics Department at William and Mary. I have enjoyed, as well as benefited, from my interactions with the faculty and staff. I would have never been able maintain my student status without the assistance of Paula, Dianne, and Sylvia. Thank you for you guidance as well as the enjoyable conversations throughout the years. I would also like to acknowledge Ed, Mel, Kirk, and John. You all have been extremely helpful. You were never too busy to take a question or give me some help.
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