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Étude Des Mécanismes De Refroidissement Du Manteau Terrestre Simulés Par Des Systèmes Multi-Agents Manuel Combes

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Étude Des Mécanismes De Refroidissement Du Manteau Terrestre Simulés Par Des Systèmes Multi-Agents Manuel Combes Étude des mécanismes de refroidissement du manteau terrestre simulés par des systèmes multi-agents Manuel Combes To cite this version: Manuel Combes. Étude des mécanismes de refroidissement du manteau terrestre simulés par des systèmes multi-agents. Géophysique [physics.geo-ph]. Université de Bretagne occidentale - Brest, 2011. Français. tel-00874975 HAL Id: tel-00874975 https://tel.archives-ouvertes.fr/tel-00874975 Submitted on 20 Oct 2013 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Universite´ Europeenne´ de Bretagne — M´emoire de th`ese — Sp´ecialit´e: Physique Etude´ des m´ecanismes de refroidissement du manteau terrestre simul´es par des syst`emes multi-agents Manuel Combes Soutenue le 10 novembre 2011 devant la commission d’examen : Rapporteurs Ga¨el Choblet Charg´ede Recherche `al’Universit´ede Nantes St´ephane Labrosse Professeur `al’ENS de Lyon Examinateurs Claude Jaupart Professeur `al’Institut de Physique du Globe Marc Parenthoen¨ Maitre de Conf´erences `al’ENI de Brest Yanick Ricard Directeur de Recherche `al’Universit´ede Lyon 1 Jacques Tisseau Professeur `al’ENI de Brest Etude´ des m´ecanismes de refroidissement du manteau terrestre simul´es par des syst`emes multi-agents M´emoire de th`ese Manuel Combes — novembre 2011 — M´emoire de th`ese Laboratoire d’Informatique des SYst`emes Complexes EA 3883 UBO-ENIB Manuel Combes e-mail : [email protected] tel : +33 (0)2 98 05 89 77 Ecole´ Normale Sup´erieure de Cachan D´epartement de Physique 61, avenue du Pr´esident Wilson 94230 Cachan (http://www.ens-cachan.fr/) Centre Europ´een de R´ealit´eVirtuelle (CERV) Technopˆole Brest-Iroise 25, rue Claude Chappe BP 38 F-29280 Plouzan´e (http://www.cerv.fr) ii Manuel Combes Remerciements Je remercie sinc`erement St´ephane Labrosse et Ga¨el Choblet d’avoir accept´e d’ˆetre rapporteurs de cette th`ese, ainsi que Yanick Ricard et Claude Jaupart qui m’ont fait l’honneur d’accepter de faire partie du jury. Toute ma gratitude va `aC´ecile Grign´e, Laurent Husson et Marc Parentho¨en, qui m’ont consacr´ebeaucoup de temps et qui ont toujours su me mettre `al’aise et r´epondre `ames questions de b´eotien. J’ai pass´eavec eux de nombreuses heures de r´eflexion qui furent parmi les plus stimulantes de ma th`ese. Merci aussi `aClint Conrad, dont les nuits sont aussi courtes que les miennes, mais les id´ees beaucoup moins! Je tiens aussi `aremercier l’ensemble des personnes qui ont contribu´e`ala r´eussite de cette th`ese, sur le plan acad´emique mais aussi sur la plan affectif, car je n’ai pas men´ecette barque seul. J’adresse donc un grand merci : A` Mireille Tadjeddine, Jean-Fran¸cois Roch et Emmanuelle Deleporte pour m’avoir accueilli avec bienveillance dans une formation de grande qualit´e`a l’Ecole´ Normale Sup´erieure de Cachan. Je dois aussi `al’ENS l’attribution de l’allocation coupl´ee qui a financ´ecette th`ese. A` Yvon Le Gall, Laurent Beau et Claire Maissiat, avec qui j’ai eu un plaisir immense `a travailler en classes pr´eparatoires `aBrest. Leurs conseils furent pr´ecieux... et fructueux ! A` Christian Brosseau, directeur de l’´ecole doctorale SICMA, qui m’a permis par deux fois d’ouvrir mes horizons de recherche, ainsi qu’`aMich`ele Kerleroux, dont la bonne humeur a su ´egayer mon parcours `al’UBO. A` Jacques Tisseau, qui a accompagn´ece travail de bout en bout, avec une exigence bienveillante et une libert´erare. La r´eussite de cette th`ese lui doit beaucoup. Je remercie l’ensemble des gens que j’ai cˆotoy´es au CERV, qui est un lieu incroyable pour faire sa th`ese. En particulier, merci `aPascal et Delphine, qui m’ont t´emoign´ependant ces trois ann´ees un optimisme sans faille et une joie de vivre tr`es contagieuse. Ma plus plate gratitude va bien sˆur `aGobito et Fabriceps, qui m’ont enseign´ela po´esie du Dr Kuntz et transmis leur goˆut pour la moustache d’halt´erophile. Et bravo `aKaren pour son assiduit´e. A` David et Sophie, pour leur amiti´esinc`ere et pour nos moments simples. Pour le monde que nous avons si souvent refait et qui s’en porte certainement mieux. A` Fr´ed´eric Massias pour ses innombrables coups de main et pour sa sympathie. Les d´ejeuners de la Butte aux Cailles sont un plaisir chaque fois renouvel´e. Merci `aClaude Jaupart pour le temps d´eraisonnable qu’il m’a consacr´eavant que je ne choisisse d’´etudier le refroidissement de la Terre, et pour ses pr´ecieux conseils de lecture. Nos discussions m’ont Manuscrit de these` iii Remerciements ouvert les yeux sur la richesse du paysage g´eophysique et sur la n´ecessit´ed’en ˆetre conscient afin de poser une question utile. A` Nicolas Tancrez pour ses ´eclairages p´edagogiques et thermodynamiques, `aNicolas Sator qui reste pour moi un exemple de simplicit´e et d’engagement trop rare dans le monde universitaire. Merci `aMady Elias´ pour son temps et son amiti´e. Un grand merci `aBernhard Steinberger, Arnaud Heuret, Claude Guennou, Yann Boucher et bien sˆur Jacques Deverch`ere pour leurs r´eponses cisel´ees `ames questions mal pos´ees. Toute ma reconnaissance va naturellement `ames relecteurs assidus : C´ecile, Pascal, Yann, Jacques, Marc, Chantal et Jacques. Merci aussi `aM´elane la foudre rousse, pour ses conseils de lecture, son enthousiasme et son inalt´erable curiosit´e. Et bien sˆur merci aux Melonais, qui me ram`enent les pieds sur Terre quand j’oublie le goˆut des brennig. Mon parcours d´ecoule tr`es largement du goˆut que l’on a su me donner pour les ´etudes et pour l’esprit critique qu’elles requi`erent. C’est `ames parents que je dois ce plaisir-l`a. Leur compr´ehension et leur soutien ind´efectible me sont des atouts au quotidien ! Durant cette th`ese, j’ai pris beaucoup de plaisir `ame creuser la tˆete, `a´elaborer des argumentations ´eph´em`eres, `afaire cent fois le tour d’une question mal pos´ee. Ce plaisir me vient des innombrables peleas et autres joutes avec mon excellent fr`ere, dont l’opinion passe pour moi toujours avant celle des autres, mˆeme s’il feint de l’ignorer. Je tiens enfin `aremercier ceux qui m’ont ´eveill´e`ades choses sans doute plus profondes et certainement plus importantes que la physique : merci `aSophie et Isabelle, pour m’avoir si souvent pris sous leur aile, et un immense merci `amon grand Jojo que j’admire pour sa science comme pour sa conscience. Je dois enfin beaucoup `aMichel, qui fut le premier `afaire de moi un physicien en herbe et qui m’a appris `ar´efl´echir dans le bon sens, mˆeme quand la barque tangue. J’ai une pens´ee toute particuli`ere pour toi en ´ecrivant ces lignes. Je voudrais enfin dire `aDani`ele combien elle me manque, mˆeme si elle m’aurait dit en riant de bon cœur : ”Allons mon petit, ne t’embˆete pas avec ¸ca...” Plus qu’`atout autre, je veux dire ma reconnaissance `aDulcinea, pour la patience d´eraisonnable dont elle fait preuve avec moi. Je te promets que d´esormais je ne planterai plus d’arbres fruitiers en pleine nuit, et que nous irons pˆecher en kayak avec des pimoussitos aux pieds nus. Enfin, je souhaite beaucoup de bonheur `ala petite Suzie, qui vient de d´ebouler ! iv Manuel Combes Avant-propos Ce manuscrit de th`ese s’adresse `adeux types de lecteur : le g´eophysicien et le mod´elisateur de syst`emes physiques complexes. Le premier trouvera dans ces pages une m´ethode originale d’´etude des m´ecanismes de refroidissement du manteau terrestre, et le second pourra ´etudier dans le d´etail la mise en œuvre d’une m´ethode de mod´elisation multi- agents de deux ph´enom`enes physiques complexes. Dans un souci de clart´eet d’accessibilit´e de ce manuscrit pour un lecteur qui n’est pas familier avec la convection mantellique ou la th´eorie cin´etique des gaz, nous exposerons en premier lieu les concepts g´en´eraux utiles `ala compr´ehension de ce travail de recherche, dans des termes que nous voulons simples. Ce manuscrit contient par ailleurs un glossaire qui propose au lecteur une explicitation des concepts sp´ecifiques aux domaines de la g´eophysique, de la thermodynamique et des outils informatiques mis en œuvre. Les m´ethodes d´evelopp´ees au cours de cette th`ese ont vocation `a ˆetre appliqu´ees `a des domaines vari´es de la physique au sens large, mˆeme si nous nous focaliserons dans ce manuscrit sur les m´ecanismes de refroidissement du manteau terrestre. A` titre d’exemple, les m´ethodes informatiques utilis´ees dans notre ´etude g´eophysique ont fait l’objet d’une application pr´ealable `ala thermodynamique des gaz, qui est un sujet dont la robustesse th´eorique nous a permis de valider l’approche multi-agents que nous proposons pour l’´etude des syst`emes complexes. Cette ´etude pr´eliminaire a pris fin en mai 2010 avec la pr´esentation de nos r´esultats `ala communaut´ede simulation num´erique des ph´enom`enes physiques `a Amsterdam (Simulation of Multiphysics Multiscale Systems, International Conference of Computational Science, Combes et al.
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