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Leidenfrost Effect at Its Limits

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Leidenfrost Effect at Its Limits Universit´ede Li`ege Universit´eLibre de Bruxelles Facult´edes Sciences Ecole´ Polytechnique Unit´ede recherche CESAM TIPs GRASP Leidenfrost effect at its limits Laurent Maquet In partial fulfillment of the requirements For the degree of Doctor of Philosophy In the subject of physics Academic year 2016-2017 2 Thanks Tout a commenc´eil y a un peu plus de cinq ans, lors du m´emoirede master... Cinq ans que je tra^ınedans les couloirs du 3`eme ´etage,et pas que. La liste des personnes `aremercier pour ces ann´eesest longue. Merci aux diff´erents membres du jury. C¸a me fait particuli`erement plaisir d'avoir pu constituer un jury avec tant de diversit´etant sur les comp´etences que sur les points d'int´er^ets.Merci `aAlejandro Silhanek d'avoir accept´ed'^etre pr´esident du jury, dans un domaine qui n'est pas le sien; `aGeoffroy Lumay, la petite secr´etaire, et bien plus encore; to Neil Shirtcliffe, who accepted to come from Germany and who will be the guarantor of English in a french jury; `aPhilippe Brunet que j'avais eu plaisir `arencontrer `aParis, et qui, par son int´er^et,avait r´eussi`ame faire parler de Leidenfrost dans des circonstances festives. Et enfin merci `aDenis Terwagne, pour sa pr´esencedans le jury au- tant que pour ses ann´eesau labos et la trace qu'il y a laiss´ee, et que pour son enseignement qui a fait partie des personnes qui font que je suis `al'ULg depuis dix ans. Ensuite, bien s^ur,il y a Pierre Colinet. Durant ces ann´eesde collabora- tions, nous avons r´eguli`erement eu des points de vue diff´erents sur certains sujets et notamment sur l'´ecriture,mais cette th`esen'aurait d´efinitivement pas ´et´ela m^emesans ton apport de rigueur et de th´eorie. Enfin, last (of the jury) but not least, St´ephaneDorobolo... Doroblo... Dorbolo ! Je pense que tu sais d´ej`aassez bien `aquel point tu as ´et´eincroyable pendant ces ann´ees,bien que tu sois trop modeste pour l'avouer. Scientifique- ment, ¸caa ´et´eun plaisir de devenir un peu ton troisi`eme fils spirituel apr`es Denis et Martin, en travaillant sur un sujet aussi passionnant que l’effet Lei- denfrost, et en laissant libre court `atoutes les id´eeset en les nourissant de ton imagination et de tes questions. Ensuite, personnellement, ¸caa ´et´epar- ii ticuli`erement enrichissant. Pour les d´ebatsdu matin, pour les pcr, pour la culture cin´ematographique,pour le punk... Il y a encore plusieurs ribambelles de gens qui ont encore jou´eun r^oletout particulier dans cette th`ese.Ceux qui ont eu un apport direct... D'abord bien s^ur,mon fr`erede th`ese,Martin Brandenbourger. Ton int´er^etpour tout ce qui t'entoure a peut-^etrecarr´ement ´et´eplus inspirant que nos discussions de geek et que les innombrables cocktails que tu as pu inventer. Ensuite, Bap- tiste Darbois-Texier. Peut-^etrele scientifique le plus impressionnant de son ^ageque j'aie rencontr´e,pour sa culture, sa capacit´e`as'int´eresser`aabsolu- ment tout... En science comme ailleurs dans le monde. Ma th`esene serait certainement pas aussi chouette sans les manipes qu'on a pu faire ensemble et toutes les discussions qu'on a pu avoir. Et puis, Alexis Duchesne, le petit dernier. Et pourtant, `al'origine d'une id´eede manipe qui a finallement ´et´e `al'origine d'une petite moiti´ede ma th`ese. Au final, on a assez peu manip´e ensemble, mais sans toi et Martin, je ne me serai jamais demand´esi mes setup exp´erimentaux ´etaient un peu foireux. Enfin, ceux qui ont eu les mains dans le cambouis pour moi, qui ont fait que certaines mes manipes ´etaient propres : Samuel Rondia et M´ed´ericM´elard,les m´ecanicienset ´electroniciensque tout le monde regrette en quittant Li`ege. Puis il y a tous les autres du labo, avec qui j'ai eu plus ou moins de rap- ports scientifiques et humains... Le tr`esancien, Christophe, qui m'a donn´ela confirmation que mettre de la musique et des blagues dans mes talks ´etaitune bonne chose, avant m^eque je ne rentre `al'universit´e. Les anciens, Florian, mon premier copromoteur `al'´epoque du m´emoire;Fran¸cois,le num´ericien- math´ematicienqui m'aura fait exploser le plus souvent; Nicolas, dit Bob, avec ses bouibouibouiiis; Charles, dix ans de course pour savoir qui serait dipl^om´e en premier, et j'accepte ma d´efaite.Ceux qui sont encore l`a:Eric, l'un de ceux qui m'ont aid´edans ma th`ese-bis,m^eme si je ne suis pas s^urd'avoir d´ej`amon titre de docteur `esMagic; Marti le puissant, pour avoir renforc´emon corps en le d´efon¸cant au foot; Sofienne, le quatri`emefils, celui que j'ai enferm´e;Pierre- Brice, le dernier Fran¸caisqu'on a ramen´ede Paris dans nos valises, aussi fort que les autres m^emes'il ne le sait pas; Herv´e,dont je me demande toujours si c'est son ouverture sur le monde qui lui donne son c^ot´eaigre-doux; Nicolas, le chef; Maxime, l'elfe avec la hallebarde, dit aussi, le magicien qui rate ses sorts; S´ebastien,le plus nouveau des nouveaux, ma rel`eve au labo; Boris, la preuve que les m´etalleuxsont tr`esurbains (mais un peu s^alesquand m^eme);Floriane et Antonella, la touche f´emininedu labo, expertes en presque-germanisme et iii pisco (resp.); Martin, deuxi`emedu nom, la force tranquille, toujours pr^et `a aider; Galien, un mec qui s'appelle trop-cool-Grosjean et qui est la preuve que m^emesans cheveux longs, les m´etalleuxsont tr`esurbains (mais un peu s^alesquand m^eme).Et puis, Alice, qui n'est pas vraiment du labo, mais qui a facilement trouv le moyen de s'intgrer dans la bande. Et enfin, mes co-bureau, S´ebastien,il me semble qu'il est un peu nerveux. Et puis Julien, dix ans de non-course pour savoir qui ne sortirait pas en premier, j'admets ma d´efaite, mais c'est bien parce que bon, hein, voil`a,OK ?! Tu te calmes ! Ensuite, ce n'est pas fini... Il y a les Bruxellois avec qui j'ai eu des dis- cussions et avec qui j'ai pu collaborer aussi. Benjamin et Alex, deux moiti´es fort diff´erentes d'un m^eme duo. Vous aussi, votre contribution directe `acette th`eseest non-n´egligeable,m^emesi je ne suis toujours pas compl`etement cer- tain d'avoir saisi la diff´erenceentre patching et matching. Quand je suis pass´e`aParis, j'ai eu la chance de travailler avec des gens qui n'ont eu finalement que peu d'apport direct, dans cette th`ese,mais qui en vrai, ont eu un tr`esgros apport indirect. Christophe Clanet, pour sa rigueur, son exigence, et le fourmillement d'id´eesqui passent par sa t^ete,reste un mod`ele pour moi. Et bien entendu, Eline.´ Les trois mois que j'ai pass´e`aParis, et le mois et demi que tu as pass´e`aLi`egeont ´et´efantastiques, et ton entrain, ton sourire et tes gentils mots ont, alors et depuis, ´et´etr`esagr´eableset motivants. Il y a aussi Pascal, Adrien, Caro, Guillaume, Dan, Lo¨ıc,Thomas, et je pour- rais m^emeciter Mourad... Mais en vrai, la liste ne s'arr^etepas l`a. For a few month, I also had the opportunity to work with Tadd Truscott. The coolest guy I met from the United States, and one of the coolest guy ever. Une mention sp´ecialepour l'homme qui m'a donn´el'envie de faire de la physique mon m´etier.Michel Kapenyak, toi et tes folles exp´eriencesdans les couloirs et en classe (au hasard, monter sur un chariot pour illustrer le MRUA, le slinky pour illustrer les propri´et´es des ondes, et la s´eancede Star Wars en ´electro-magn´etisme)avez ´et´ecapitaux pour me pousser jusqu'ici. Enfin, il y a tous les autres qui m'ont entour´eces derni`eresann´ees. Im- possible de tous les citer, sinon je vais oublier des gens, mais les gars de Black Sun Act, et en particulier Fran¸cois,les gens de l'univ, les touristes et assimil´es, ceux du badminton, de l'universit´eMagic, et de la team JangaDa... iv Et puis bien entendu, ma famille qui a ´et´ela premi`ere`ame donner la passion des sciences il y a bien longtemps, en me faisant jouer avec des l´egos, des dinosaures et en me faisant lire des bouquins sur l'astro. Heureusement que je n'ai pas vir´eing´enieurou gratteur de caillou, quand m^eme... Li`ege,November 2016 Laurent Maquet Table of Contents Thanks i Summary i R´esum´e i I Introduction 1 I.1 A story of drops . 1 I.1.1 A way to overcome contacts . 3 I.1.2 Superhydrophobicity in a nutshell . 4 I.2 Levitating drops . 4 I.2.1 The analytical model . 8 I.2.2 The numerical model . 10 I.3 Outline . 12 References . 14 II Hypergravity 17 II.1 Introduction . 17 II.2 Experimental details . 18 II.3 Lifetimes : a basic concern . 19 II.4 The Leidenfrost Point : the unsolved question . 22 II.5 Supersize the drops ! . 24 II.6 Conclusions . 26 References . 27 III Liquid substrates 29 III.1 Preamble .
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