{"id":48863,"date":"2021-12-09T11:10:30","date_gmt":"2021-12-09T09:10:30","guid":{"rendered":"https:\/\/www.iemn.fr\/?p=48863"},"modified":"2022-03-04T13:47:12","modified_gmt":"2022-03-04T11:47:12","slug":"these-de-guillaume-cousin-modelisation-modale-de-la-transduction-de-patch-magnetostrictif-pour-le-rayonnement-dondes-elastiques-guidees-en-vue-du-controle-de-sante-integre-de-structures-fin","status":"publish","type":"post","link":"https:\/\/www.iemn.fr\/en\/actualites\/these-de-guillaume-cousin-modelisation-modale-de-la-transduction-de-patch-magnetostrictif-pour-le-rayonnement-dondes-elastiques-guidees-en-vue-du-controle-de-sante-integre-de-structures-fin.html","title":{"rendered":"Guillaume Cousin's thesis - \"Modal modeling of magnetostrictive patch transduction for guided elastic wave radiation for integrated health monitoring of fine structures"},"content":{"rendered":"<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-1ajetzz-4c07e9a7a765edceecdbfde7fbb298f2\">\n.flex_column.av-1ajetzz-4c07e9a7a765edceecdbfde7fbb298f2{\nborder-radius:0px 0px 0px 0px;\npadding:0px 0px 0px 0px;\n}\n<\/style>\n<div  class='flex_column av-1ajetzz-4c07e9a7a765edceecdbfde7fbb298f2 av_one_full  avia-builder-el-0  avia-builder-el-no-sibling  first flex_column_div av-zero-column-padding'     ><section  class='av_textblock_section av-qg9qn3-22a2d7642a1ba7fe7867e2797ea0d6c7'   itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/BlogPosting\" itemprop=\"blogPost\" ><div class='avia_textblock'  itemprop=\"text\" ><h3 style=\"text-align: center;\">Th\u00e8se de Guillaume COUSIN<\/h3>\n<h4 style=\"text-align: center;\">\u00ab\u00a0Mod\u00e9lisation modale de la transduction de patch magn\u00e9tostrictif pour le rayonnement d\u2019ondes \u00e9lastiques guid\u00e9es en vue du contr\u00f4le de sant\u00e9 int\u00e9gr\u00e9 de structures fines\u00a0\u00bb<\/h4>\n<blockquote><p>\n<style type=\"text\/css\" data-created_by=\"avia_inline_auto\" id=\"style-css-av-ikveov-92c0e1e8a70f730b34d6ee48b092e96b\">\n.av_font_icon.av-ikveov-92c0e1e8a70f730b34d6ee48b092e96b .av-icon-char{\nfont-size:30px;\nline-height:30px;\n}\n<\/style>\n<span  class='av_font_icon av-ikveov-92c0e1e8a70f730b34d6ee48b092e96b avia_animate_when_visible av-icon-style- avia-icon-pos-left av-no-color avia-icon-animate'><span class='av-icon-char' aria-hidden='true' data-av_icon='\ue8c9' data-av_iconfont='entypo-fontello' ><\/span><\/span>Soutenance de th\u00e8se : le 14 d\u00e9cembre \u00e0 13h30<br \/>\nAmphi 34 du b\u00e2timent 565 Digiteolabs &#8211; CEA-Saclay<\/p>\n<\/blockquote>\n<h5>Jury :<\/h5>\n<p>Catherine POTEL, Professeure, Le Mans Universit\u00e9 (en visioconf\u00e9rence), Rapporteuse<\/p>\n<p>Frederic CEGLA, Reader, Imperial College London (en visioconf\u00e9rence), Rapporteur<\/p>\n<p>Fr\u00e9d\u00e9ric JENOT, Professeur, Universit\u00e9 Polytechnique des Hauts-de-France, Examinateur<\/p>\n<p>Philippe GUY, Ma\u00eetre de Conf\u00e9rence, INSA-Lyon, Examinateur<\/p>\n<p>S\u00e9bastien GRONDEL, Professeur, Universit\u00e9 Polytechnique des Hauts-de-France, Directeur de th\u00e8se<\/p>\n<p>Alain LH\u00c9MERY, Directeur de Recherche CEA, CEA LIST, Encadrant<\/p>\n<h5>Summary:<\/h5>\n<p>Les patchs magn\u00e9tostrictifs qui sont des transducteurs \u00e9lectro-acoustiques permettant d\u2019\u00e9mettre et de recevoir des ondes \u00e9lastiques dans les mat\u00e9riaux solides offrent une alternative particuli\u00e8rement prometteuse par comparaison avec les transducteurs pi\u00e9zo\u00e9lectriques, notamment en ce qui concerne la g\u00e9n\u00e9ration d\u2019ondes \u00e9lastiques guid\u00e9es et sp\u00e9cifiquement pour leur utilisation en contr\u00f4le sant\u00e9 int\u00e9gr\u00e9. Par d\u00e9finition, un patch magn\u00e9tostrictif est constitu\u00e9 d\u2019une fine bande d\u2019un mat\u00e9riau magn\u00e9tostrictif coupl\u00e9e \u00e0 la pi\u00e8ce dans laquelle sont cr\u00e9\u00e9es des ondes \u00e9lastiques. En outre, cette bande est magn\u00e9tis\u00e9e ou pr\u00e9-magn\u00e9tis\u00e9e et excit\u00e9e par une bobine dans laquelle circule un courant haute-fr\u00e9quence. La conception de la g\u00e9om\u00e9trie de la bobine ainsi quela mani\u00e8re dont est magn\u00e9tis\u00e9e la bande et le choix du domaine fr\u00e9quentiel d\u2019excitation aident \u00e0 cr\u00e9er diff\u00e9rentes sources m\u00e9caniques dynamiques \u00e0 la surface de la pi\u00e8ce.<br \/>\nCe travail de th\u00e8se propose un mod\u00e8le global de l\u2019ensemble des ph\u00e9nom\u00e8nes multi-physiques mis en jeu dans la transduction des patchs magn\u00e9tostrictifs, le but \u00e9tant de cr\u00e9er un outil de simulation op\u00e9rationnel pour optimiser les param\u00e8tres servant \u00e0 cr\u00e9er les ondes guid\u00e9es s\u00e9lectionn\u00e9es au sein de la plaque tels que les ondes de Lamb ou les ondes transverses de cisaillement \u00e0 polarisation horizontale. Plus pr\u00e9cis\u00e9ment, cette recherche s\u2019int\u00e9resse \u00e0 diff\u00e9rents aspects, c\u2019est-\u00e0-dire \u00e0 la cr\u00e9ation des sources \u00e9lectro-magn\u00e9to-\u00e9lastiques dans la bande magn\u00e9tostrictive, aux ondes que ces sources cr\u00e9ent et qui se propagent au sein du patch magn\u00e9tostrictif et enfin aux ondes guid\u00e9es rayonn\u00e9es dans la pi\u00e8ce. Au niveau de la m\u00e9thodologie choisie, le mod\u00e8le global est d\u00e9velopp\u00e9 suivant une approche modale et selon une strat\u00e9gie optimale visant \u00e0 minimiser les calculs num\u00e9riques. Aussi, de nouveaux mod\u00e8les d\u2019interfa\u00e7age sont \u00e9labor\u00e9s et adapt\u00e9s afin d\u2019assurer le couplage entre deux mod\u00e8les existants d\u00e9velopp\u00e9s au laboratoire, l\u2019un, non-modal, d\u00e9di\u00e9 \u00e0 la transduction \u00e9lectro-magn\u00e9to acoustique en milieu ferromagn\u00e9tique, l\u2019autre, modal, consacr\u00e9 au rayonnement d\u2019ondes guid\u00e9es par une source de contrainte \u00e0 la surface d\u2019une pi\u00e8ce. Le simulateur qui en r\u00e9sulte peut alors \u00eatre exploit\u00e9 de fa\u00e7on intensive comme cela est requis dans le cadre de travaux de conception de sources ultrasonores pour une application donn\u00e9e.<br \/>\nDans la construction du mod\u00e8le global de transduction d\u2019ondes guid\u00e9es par un patch magn\u00e9tostrictif, diff\u00e9rentes hypoth\u00e8ses et approximations sont propos\u00e9es. Afin de v\u00e9rifier leur pertinence et leur pr\u00e9cision, chacune fait l\u2019objet d\u2019une analyse et d\u2019une v\u00e9rification d\u00e9taill\u00e9e. Le mod\u00e8le global fait \u00e9galement l\u2019objet de validations th\u00e9oriques et exp\u00e9rimentales puisque l\u2019on confronte syst\u00e9matiquement les r\u00e9sultats obtenus avec soit des simulations par \u00e9l\u00e9ments finis, soit des mesures. L\u2019ensemble de ces comparaisons d\u00e9montre la capacit\u00e9 du simulateur \u00e0 traiter des configurations tr\u00e8s vari\u00e9es.<\/p>\n<h5>Abstract:<\/h5>\n<p>Magnetostrictive patches, which are electro-acoustic transducers making it possible to emit and receive elastic waves in solid materials, offer a promising alternative to piezoelectric transducers, in particular with regard to the generation of guided elastic waves and specifically for their use in structural health monitoring. A magnetostrictive patch consists of a thin strip of magnetostrictive material coupled to the part in which elastic waves are to be generated. In addition, this strip is magnetized or pre-magnetized and excited by a coil in which a high-frequency current flows. The design of the coil geometry as well as the way the strip is magnetized and the choice of the excitation frequency range help to generate different dynamic mechanical sources at the piece surface.<br \/>\nThis thesis work proposes a global model of all the multi-physical phenomena involved in the transduction of magnetostrictive patches, the goal being to create an operational simulation tool to optimize the parameters used to selectively generate guided waves in a plate such as Lamb waves or horizontally polarized shear waves. More precisely, this research is interested in different aspects, i.e. the creation of electro-magneto-elastic sources in the magnetostrictive strip, the waves that these sources create and that propagate within the magnetostrictive patch and finally to the guided waves radiated into the piece. The global model is developed according to a modal approach and according to an optimal strategy aimed at minimizing numerical calculations. New models are developed to ensure the chaining of two existing models developed in the laboratory, one, non-modal, dedicated to electro-magneto-acoustic transduction in a ferromagnetic medium, the other, modal, devoted to the radiation of guided waves by a source of stress at the surface of a part. The resulting simulator can then be used intensively as required in the context of ultrasonic source design work for a given application.<br \/>\nIn deriving the global transduction model of guided waves by a magnetostrictive patch, different assumptions and approximations are made. In order to verify their relevance and accuracy, each of these assumptions is subject to detailed analysis and verification. The global model is also the subject of theoretical and experimental validations since the results obtained are systematically compared with either finite element simulations or measurements. Taken together, these comparisons demonstrate the simulator&rsquo;s ability to deal with a wide variety of configurations.<\/p>\n<\/div><\/section><\/div>","protected":false},"excerpt":{"rendered":"","protected":false},"author":2,"featured_media":29874,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[8],"tags":[],"class_list":["post-48863","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-actualites"],"_links":{"self":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/48863","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/comments?post=48863"}],"version-history":[{"count":0,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/posts\/48863\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media\/29874"}],"wp:attachment":[{"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/media?parent=48863"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/categories?post=48863"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.iemn.fr\/en\/wp-json\/wp\/v2\/tags?post=48863"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}