. .. Samples, 130 6.1.2 Evidence of the existence of pre-hole within the sheet

.. .. , 135 6.2.2 Velocity field of the perforated liquid sheet, p.135

, Pre-hole formation due to Marangoni spreading of oil droplet at the air/water interface

.. .. Pre-hole-growth-dynamics,

, Comparison between single-tear experiments and classical Marangoni spreading experiments

, Entering and spreading of oil droplet at the air/water interface, p.152

.. .. Conclusion,

, 2.2 Effect of the addition of salt on sheet perforation and on spray formation, Contents 7.1 Entering and spreading of oil droplets at the air/water interface 156 7.2 Emulsions stabilized by anionic surfactants

. .. Cationic-surfactants, of the addition of salt and amphiphilic copolymer on the perforation mechanism

.. .. Discussion,

.. .. Conclusion,

F. O. Addo-yobo, M. J. Pitt, and H. A. Obiri, This thinning leads to the rupture of the film and so the nucleation of a hole. Hence, the proposed mechanism implies a succession of two necessary steps: (i) the entering of oil droplets at the air/water interface and (ii) the spreading of the oil droplets at the interface. This mechanism has been established thanks to the observation of the thickness modulations of liquid sheets made of model emulsions. In this chapter, we modify the physico-chemical parameters of emulsions to play on the perforation, we have proposed a mechanism for the role of dilute oilin-water emulsions as anti-drift adjuvants: the oil droplets enter the air/water interface and spread at the interface leading to a localized thinning of the liquid film due to a Marangoni stress, vol.57, 2007.

J. Ahmad and R. S. Hansen, A simple quantitative treatment of the spreading of monolayers on thin liquid films, Journal of Colloid and Interface Science, vol.38, issue.3, pp.601-604, 1972.

M. Heidary, J. P. Douzals, C. Sinfort, and A. Vallet, Influence of spray characteristics on potential spray drift of field crop sprayers: A literature review, Crop Protection, vol.63, pp.120-130, 2014.

A. Altieri, S. A. Cryer, and L. Acharya, Mechanisms, Experiment and Theory of Liquid Sheet Breakup and Drop Size from Agricultural Nozzles, Atomization and Sprays, vol.24, issue.8, pp.695-721, 2014.

Y. Amarouchene, D. Bonn, J. Meunier, and H. Kellay, Inhibition of the finite-time singularity during droplet fission of a polymeric fluid, Physical Review Letters, vol.86, issue.16, pp.2-5, 2001.
URL : https://hal.archives-ouvertes.fr/hal-01550678

T. Arvidsson, L. Bergström, and J. Kreuger, Spray drift as influenced by meteorological and technical factors, Pest Management Science, vol.67, issue.5, pp.586-598, 2011.

S. Bakshi, I. V. Roisman, and C. Tropea, Investigations on the impact of a drop onto a small spherical target, Physics of Fluids, vol.19, issue.3, p.71, 2007.

T. J. Barnes and C. A. Prestidge, PEO -PPO -PEO Block Copolymers at the Emulsion Droplet -Water Interface, Langmuir, vol.16, issue.9, p.192, 2000.

O. A. Basaran, Small scale free surface flows with breakup, drop formation and emergining applications, AIChE Journal, vol.48, issue.9, pp.1842-1848, 2004.

E. S. Basheva, D. Ganchev, N. D. Denkov, K. Kasuga, N. Satoh et al., Role of betaine as foam booster in the presence of silicone oil drops, Langmuir, vol.16, issue.6, p.201, 2000.

E. S. Basheva, S. Stoyanov, N. D. Denkov, K. Kasuga, N. Satoh et al., Foam boosting by amphiphilic molecules in the presence of silicone oil, Langmuir, vol.17, issue.7, p.201, 2001.

T. Bennett and D. Poulikakos, Splat-quench solidification: estimating the maximum spreading of a droplet impacting a solid surface, Journal of Materials Science, vol.28, issue.4, p.83, 1993.

V. Bergeron, M. E. Fagan, and C. J. Radke, Generalized entering coefficients: a criterion for foam stability against oil in porous media, Langmuir, vol.9, issue.7, p.156, 1993.

V. Bergeron and D. Langevin, Monolayer Spreading of Polydimethylsiloxane Oil on Surfactant Solutions, Physical Review Letters, vol.76, issue.17, p.145, 1996.

V. Bergeron, P. Cooper, C. Fischer, J. Giermanska-kahn, D. Langevin et al., Polydimethylsiloxane (PDMS)-based antifoams, Colloids and Surfaces A: Physicochemical and Engineering Aspects, vol.122, pp.103-120, 1997.

V. Bergeron, Designing intelligent fluids for controlling spray applications, Comptes Rendus Physique, vol.4, issue.2, pp.211-219, 2003.

M. Berhanu and E. Falcon, Space-time-resolved capillary wave turbulence, Physical Review E, vol.87, issue.3, p.74, 2013.

. Billericay-farm and . Services, , p.13

A. Bonfillon, F. Sicoli, and D. Langevin, Dynamic surface tension of ionic surfactant solutions, Journal of Colloid and Interface Science, vol.168, p.171, 1994.

N. Bremond and E. Villermaux, Atomization by jet impact, Journal of Fluid Mechanics, vol.549, pp.273-306, 2006.
URL : https://hal.archives-ouvertes.fr/hal-00094665

N. Bremond, C. Clanet, and E. Villermaux, Atomization of undulating liquid sheets, Journal of Fluid Mechanics, vol.585, pp.421-456, 2007.
URL : https://hal.archives-ouvertes.fr/hal-00264718

R. B. Brown, M. H. Carter, and G. R. Stephenson, Buffer zone and windbreak effects on spray drift deposition in a simulated wetland, Pest Management Science, vol.60, issue.11, p.11, 2004.

J. W. Bush and A. E. Hasha, On the collision of laminar jets: fluid chains and fishbones, Journal of Fluid Mechanics, vol.511, p.66, 2004.

M. C. Butler-ellis, C. R. Tuck, and P. C. Miller, The effect of some adjuvants on sprays produced by agricultural flat fan nozzles, Crop Protection, vol.16, issue.1, pp.41-50, 1997.

M. C. Butler-ellis and C. R. Tuck, How adjuvants influence spray formation with different hydraulic nozzles, Crop Protection, vol.18, issue.2, pp.101-109, 1999.

M. C. Butler-ellis, C. R. Tuck, and P. C. Miller, Dilute emulsions and their effect on the breakup of the liquid sheet produced by flat-fan spray nozzles, Atomization and Sprays, vol.9, pp.385-397, 1999.

M. C. Butler-ellis, A. G. Lane, C. M. O'sullivan, P. C. Miller, and C. R. Glass, Bystander exposure to pesticide spray drift: New data for model development and validation, Biosystems Engineering, vol.107, issue.3, pp.162-168, 2010.

B. Cabane and R. Duplessix, Organization of surfactant micelles adsorbed on a polymer molecule in water : a neutron scattering study, Journal Phys. France, vol.43, pp.1529-1542, 1982.
URL : https://hal.archives-ouvertes.fr/jpa-00209534

D. W. Camp and J. C. Berg, The spreading of oil on water in the surfacetension regime, Journal of Fluid Mechanics, vol.184, p.145, 1987.

Y. Christanti and L. M. Walker, Surface tension driven jet break up of strain-hardening polymer solutions, Journal of Non-Newtonian Fluid Mechanics, vol.100, issue.1-3, p.44, 2001.

Y. Christanti and L. M. Walker, Effect of fluid relaxation time of dilute polymer solutions on jet breakup due to a forced disturbance, Journal of Rheology, vol.46, issue.3, p.733, 2002.

]. C. Clanet and J. C. Lasheras, Transition from dripping to jetting, Journal of Fluid Mechanics, vol.383, pp.307-326, 1999.

C. Clanet and E. Villermaux, Life of a smooth liquid sheet, Journal of Fluid Mechanics, vol.462, pp.307-340, 2002.

C. J. Clark and N. Dombrowski, The dynamics of the rim of a fan spray sheet, Chemical Engineering Science, vol.26, issue.11, p.16, 1971.

C. J. Clark and N. Dombrowski, On the formation of drops from the rims of fan spray sheets, Journal of Aerosol Science, vol.3, p.16, 1972.

J. H. Combellack, N. M. Westen, and R. G. Richardson, A comparison of the drift potential of a novel twin fluid nozzle with conventional low volume flat fan nozzles when using a range of adjuvants, Crop Protection, vol.15, issue.2, pp.147-152, 1996.

F. E. Culick, Comments on a Ruptured Soap Film, Journal of Applied Physics, vol.31, issue.6, p.139, 1960.

N. D. Denkov, Mechanisms of foam destruction by oil-based antifoams, Langmuir, vol.20, issue.22, pp.9463-505, 2004.

N. D. Denkov, K. G. Marinova, and S. S. Tcholakova, Mechanistic understanding of the modes of action of foam control agents, Advances in Colloid and Interface Science, vol.206, p.157, 2013.

R. W. Dexter, Measurement of extensional viscosity of polymer solutions and its effects on atomization from a spray nozzle, Atomization and Sprays, vol.6, pp.167-191, 1996.

R. W. Dexter, The effect of fluid properties on spray quality from a flat fan nozzle, Pesticide formulations and application systems: twentieth volume, ASTM STP 1400, 2001.

R. Dhiman and S. Chandra, Rupture of thin films formed during droplet impact, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, vol.466, p.73, 2010.

N. D. Dipietro, C. Huh, and R. G. Cox, The hydrodynamics of the spreading of one liquid on the surface of another, Journal of Fluid Mechanics, vol.84, issue.03, p.145, 2006.

N. Dombrowski and R. P. Fraser, A photographic investigation into the disintegration of liquid sheets, Philosophical transactions of the Royal Society of London. Series A, Mathematical, Physical and Engineering sciences, vol.247, p.16, 1954.

N. Dombrowski, D. Hasson, and D. E. Ward, Some aspects of liquid flow through fan spray nozzles, Chemical Engineering Science, vol.12, pp.35-50, 1960.

G. J. Dorr, A. J. Hewitt, S. W. Adkins, J. Hanan, H. Zhang et al., A comparison of initial spray characteristics produced by agricultural nozzles, Crop Protection, vol.53, pp.109-117, 2013.

A. D. Dussaud and S. M. Troian, Dynamics of spontaneous spreading with evaporation on a deep fluid layer, Physics of Fluids, vol.10, issue.1, pp.23-38, 1998.

A. D. Dussaud, O. K. Matar, and S. M. Troian, Spreading characteristics of an insoluble surfactant film on a thin liquid layer: comparison between theory and experiment, Journal of Fluid Mechanics, vol.544, p.145, 2005.

]. J. Eggers, Universal pinching of 3D axisymmetric free-surface flow, Physical Review Letters, vol.71, issue.21, pp.3458-3460, 1993.

J. Eggers and E. Villermaux, Physics of liquid jets. Reports on Progress in Physics, vol.71, issue.3, p.36601, 2008.

J. Eggers, M. Fontelos, C. Josserand, and S. Zaleski, Drop dynamics after impact on a solid wall: Theory and simulations, Physics of Fluids, vol.22, issue.6, p.62101, 2010.

J. A. Fay, The spread of oil slicks on a calm sea, vol.143, 1969.

, Report of the FOCUS working group on landscape and mitigation factors in ecological risk assessment, EC document reference SANCO/10422/2005 v2.0. Rapport technique, FOCUS, vol.1, p.24, 2007.

, Report of the FOCUS working group on landscape and mitigation factors in ecological risk assessment, EC document reference SANCO/10422/2005 v2.0. Rapport technique, FOCUS, vol.2, p.24, 2007.

M. Foda and R. G. Cox, The spreading of thin liquid films on a water-air interface, Journal of Fluid Mechanics, vol.101, issue.1, p.33, 1980.

C. Frese, S. Ruppert, M. Sugár, H. Schmidt-lewerkühne, K. P. Wittern et al., Adsorption kinetics of surfactant mixtures from micellar solutions as studied by maximum bubble pressure technique, Journal of Colloid and Interface Science, vol.267, issue.2, p.171, 2003.

S. Gart, B. Chang, B. Slama, R. Goodnight, S. H. Um et al., Dynamics of squeezing fluids: Clapping wet hands, Physical Review E, vol.88, issue.2, p.23007, 2013.

D. P. Gaver and J. B. Grotberg, The dynamics of a localized surfactant on a thin film, Journal of Fluid Mechanics, vol.213, issue.1, p.145, 2006.

J. M. Green and G. B. Beestman, Recently patented and commercialized formulation and adjuvant technology, Crop Protection, vol.26, issue.3, p.14, 2007.
DOI : 10.1016/j.cropro.2005.04.018

R. Grisso, P. Hipkins, S. D. Askew, L. Hipkins, and D. Mccall, Nozzles : Selection and Sizing. Rapport technique, vol.10, 2013.

A. Hadjiiski, S. Tcholakova, N. D. Denkov, P. Durbut, G. Broze et al., Effect of oily additives on foamability and foam stability -2. Entry barriers. Langmuir, vol.17, pp.6999-7010, 2001.

W. D. Harkins, A general thermodynamic theory of the spreading of liquids to form duplex films and of liquids or solids to form monolayers, The Journal of Chemical Physics, vol.9, pp.552-568, 1941.

]. K. Hayakawa and J. T. Kwak, Holland, editeurs, Cationic surfactants physical chemistry, vol.176, p.189, 1991.

E. Hilz, A. V. Vermeer, M. A. Stuart, and F. A. Leermakers, Mechanism of perforation based on spreading properties of emulsified oil, Atomization and Sprays, vol.22, issue.12, pp.1053-1075, 2013.

E. Hilz and A. W. Vermeer, Spray drift review: The extent to which a formulation can contribute to spray drift reduction, Crop Protection, vol.44, pp.75-83, 2013.

H. J. Holterman, Kinetics and evaporation of water drops in air, Rapport technique July, Institute of Agricultural and Environmental Engendering, 2003.

N. E. Hotrum, T. Vliet, M. A. Stuart, and G. A. Van-aken, Monitoring entering and spreading of emulsion droplets at an expanding air/water interface: a novel technique, Journal of Colloid and Interface Science, vol.247, issue.1, p.172, 2002.

P. Joos and J. Pintens, Spreading kinetics of liquids on liquids, Journal of Colloid and Interface Science, vol.60, issue.3, p.142, 1977.

J. B. Keller and M. J. Miksis, Surface tension driven flows, SIAM Journal on Applied Mathematics, vol.43, issue.2, pp.268-277, 1983.

J. Kim and M. H. Kim, A photochromic dye activation method for measuring the thickness of liquid films, Bulletin-Korean Chemical Society, vol.26, issue.6, p.74, 2005.

H. Lastakowski, F. Boyer, A. L. Biance, C. Pirat, and C. Ybert, Bridging local to global dynamics of drop impact onto solid substrates, Journal of Fluid Mechanics, vol.747, pp.103-118, 2014.
URL : https://hal.archives-ouvertes.fr/hal-01628782

F. Leal-calderon, V. Schmitt, and J. Bibette, Emulsion science basic principles, vol.40, 2007.
URL : https://hal.archives-ouvertes.fr/hal-00801651

A. H. Lefebvre, Atomization and Sprays. Hemisphere Publishing Corporation, p.103, 1989.
DOI : 10.1201/9781482227857

H. Lhuissier and E. Villermaux, Effervescent atomization in two dimensions, Journal of Fluid Mechanics, vol.714, pp.361-392, 2013.
URL : https://hal.archives-ouvertes.fr/hal-00948621

L. U. Lilleleht and T. J. Hanratty, Measurement of interfacial structure for co-current air-water flow, Journal of Fluid Mechanics, vol.11, issue.1, p.74, 1961.

S. V. Makarytchev, T. A. Langrish, and R. G. Prince, Thickness and velocity of wavy liquid films on rotating conical surfaces, Chemical Engineering Science, vol.56, p.74, 2001.

M. Marengo, C. Antonini, I. V. Roisman, and C. Tropea, Drop collisions with simple and complex surfaces, Current Opinion in Colloid & Interface Science, vol.16, issue.4, pp.292-302, 2011.

R. Matuura, H. Kimizuka, S. Miyamoto, and R. Shimozawa, The Study of the Adsorption of Detergents at a Solution-Air Interface by Radiotracer Method. I. Adsorption Isotherm for the Solution of Sodium Alkyl Sulfates, Bulletin of the Chemical Society of Japan, vol.31, issue.5, p.171, 1958.

P. C. Miller, M. C. Butler, and . Ellis, Effects of formulation on spray nozzle performance for applications from ground-based boom sprayers, Crop Protection, vol.19, issue.8-10, pp.609-615, 2000.

P. C. Miller, Spray Drift. Pesticide Outlook, pp.205-209, 2003.

E. Miller, B. Gibson, E. Mcwilliams, and J. P. Rothstein, Collision of viscoelastic jets and the formation of fluid webs, Applied Physics Letters, vol.87, issue.1, p.66, 2005.

P. C. Miller, M. C. Butler-ellis, A. G. Lane, C. M. Sullivan, and C. R. Tuck, Methods for minimising drift and off-target exposure from boom sprayer applications, Aspects of Applied Biology, vol.106, pp.281-288, 2011.

F. R. Molino, J. Berret, G. Porte, O. Diat, and P. Lindner, Identification of flow mechanisms for a soft crystal, The European Physical Journal B, vol.3, issue.1, pp.59-72, 1998.

A. A. Mouza, N. A. Vlachos, S. V. Paras, and A. J. Karabelas, Measurement of liquid film thickness using a laser light absorption method, Experiments in Fluids, vol.28, p.74, 2000.

R. P. Mun, J. A. Byars, and D. V. Boger, The effects of polymer concentration and molecular weight on the breakup of laminar capillary jets, Journal of NonNewtonian Fluid Mechanics, vol.74, issue.1-3, pp.285-297, 1998.

R. P. Mun, B. W. Young, and D. V. Boger, Atomisation of dilute polymer solutions in agricultural spray nozzles, Journal of Non-Newtonian Fluid Mechanics, vol.83, issue.1-2, pp.163-178, 1999.

S. D. Murphy, P. C. Miller, and C. S. Parkin, The Effect of Boom Section and Nozzle Configuration on the Risk of Spray Drift, Journal of Agricultural Engineering Research, vol.75, issue.2, pp.127-137, 2000.

D. Nuyttens, K. Baetens, M. De-schampheleire, and B. Sonck, Effect of nozzle type, size and pressure on spray droplet characteristics, Biosystems Engineering, vol.97, issue.3, pp.333-345, 2007.

E. C. Oerke and H. W. Dehne, Safeguarding production -Losses in major crops and the role of crop protection, Crop Protection, vol.23, issue.4, pp.275-285, 2004.

T. Ohyama, K. Endoh, A. Mikami, and Y. H. Mori, Optical interferometry for measuring instantaneous thickness of transparent solid and liquid films, Review of Scientific Instruments, vol.59, p.74, 1988.

D. T. Papageorgiou, On the breakup of viscous liquid threads, Physics of Fluids, vol.7, issue.7, p.1529, 1995.

O. Permin, L. N. Jø-rgensen, and K. Persson, Deposition characteristics and biological effectiveness of fungicides applied to winter wheat and the hazards of drift when using different types of hydraulic nozzles, Crop Protection, vol.11, issue.6, pp.541-546, 1992.

K. Qin, H. Tank, S. Wilson, B. Downer, and L. Liu, Controlling Droplet-Size Distribution Using Oil Emulsions in Agricultural Sprays, Atomization and Sprays, vol.20, issue.3, pp.227-239, 2010.

A. Rozhkov, B. Prunet-foch, and M. Vignes-adler, Impact of water drops on small targets, Physics of Fluids, vol.14, issue.10, pp.3485-3501, 2002.
URL : https://hal.archives-ouvertes.fr/hal-00693608

A. Rozhkov, B. Prunet-foch, and M. Vignes-adler, Dynamics of a liquid lamella resulting from the impact of a water drop on a small target, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, vol.460, pp.2681-2704, 2004.
URL : https://hal.archives-ouvertes.fr/hal-00693878

A. Rozhkov, B. Prunet-foch, and M. Vignes-adler, Dynamics and disintegration of drops of polymeric liquids, Journal of Non-Newtonian Fluid Mechanics, vol.134, p.98, 2006.
URL : https://hal.archives-ouvertes.fr/hal-00019005

A. Rozhkov, B. Prunet-foch, and M. Vignes-adler, Impact of drops of surfactant solutions on small targets, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, vol.466, issue.2122, p.94, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00515254

F. Savart, Mémoire sur le choc d'une veine liquide lancée contre un plan circulaire, Ann. de Chim, vol.54, p.1833

M. L. Sheely, Glycerol viscosity tables, Industrial and Engineering Chemisty, vol.24, issue.9, pp.1060-1064, 1932.

T. M. Spielbauer and C. K. Aidun, The cause and effects of perforations in a liquid sheet from a splash-plate spray nozzle, Atomization and Sprays, issue.514, p.19, 1994.

C. Stainier, M. F. Destain, B. Schiffers, and F. Lebeau, Droplet size spectra and drift effect of two phenmedipham formulations and four adjuvants mixtures, Crop Protection, vol.25, issue.12, pp.1238-1243, 2006.

G. R. Stephenson, I. G. Ferris, P. T. Holland, and M. Nordberg, Glossary of terms relating to pesticides (IUPAC Recommendations, Pure and Applied Chemistry, vol.78, issue.11, pp.2075-2154, 2006.

G. I. Taylor, The dynamics of thin sheets of fluid iii. disintegration of fluid sheets, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, vol.253, pp.313-321, 1959.

W. A. Taylor, A. R. Womac, P. C. Miller, and B. P. Taylor, An Attempt to Relate Drop Size to Drift Risk. International conference on pesticide Application for drift management Octobre 27-29, pp.210-223, 2004.

S. T. Thoroddsen, K. Takehara, and T. G. Etoh, Micro-splashing by drop impacts, Journal of Fluid Mechanics, vol.706, pp.560-570, 2012.
DOI : 10.1017/jfm.2012.281

C. B. Tibiriçá, F. J. Nascimento, and G. Ribatski, Film thickness measurement techniques applied to micro-scale two-phase flow systems, Experimental Thermal and Fluid Science, vol.34, issue.4, p.74, 2010.

V. Tirtaatmadja, G. H. Mckinley, and J. J. Cooper-white, Drop formation and breakup of low viscosity elastic fluids: Effects of molecular weight and concentration, Physics of Fluids, vol.18, issue.4, p.43101, 2006.

. Topps-]-topps, Train operators to promote best management practices and sustainability -Water protection, vol.12

I. M. Umlong and K. Ismail, Micellization behaviour of sodium dodecyl sulfate in different electrolyte media, Colloids and Surfaces A: Physicochemical and Engineering Aspects, vol.299, issue.1-3, pp.8-14, 2007.

A. Vallet and C. Tinet, Surfactant Influence on Droplet Size and Velocity Spectra from Hollow Cone and Air Induced Sprays, Journal of Agricultural Science and Technology B, vol.1, p.104, 2011.

A. Vallet and C. Tinet, Characteristics of droplets from single and twin jet air induction nozzles: A preliminary investigation, Crop Protection, vol.48, p.104, 2013.

J. C. Van-de-zande, H. J. Holterman, and H. A. Porskamp, Influence of reference nozzle choice on spray drift classification, International conference on pesticide application for drift management, vol.03, p.103, 2004.

P. Vassallo and N. Ashgriz, Satellite formation and merging in liquid jet breakup, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences, vol.433, p.44, 1991.

C. Vernay, L. Ramos, J. P. Douzals, R. Goyal, J. C. Castaing et al., Drop impact experiment as a model experiment to investigate the role of oil-in-water emulsions in controlling the drop size distribution of an agricultural spray, press, Atomization and Sprays, vol.208, 2015.
URL : https://hal.archives-ouvertes.fr/hal-01304654

C. Vernay, L. Ramos, and C. Ligoure, Bursting of Dilute Emulsion-Based Liquid Sheets Driven by a Marangoni Effect, Physical Review Letters, vol.115, issue.19, p.198302, 2015.
URL : https://hal.archives-ouvertes.fr/hal-01370655

C. Vernay, L. Ramos, and C. Ligoure, Free radially expanding liquid sheet in air: time-and space-resolved measurement of the thickness field, Journal of Fluid Mechanics, vol.764, p.66, 2015.
URL : https://hal.archives-ouvertes.fr/hal-01104008

E. Villermaux and C. Clanet, Life of a flapping liquid sheet, Journal of Fluid Mechanics, vol.462, p.16, 2002.

E. Villermaux and B. Bossa, Drop fragmentation on impact, Journal of Fluid Mechanics, vol.668, pp.412-435, 2011.
URL : https://hal.archives-ouvertes.fr/hal-00714173

C. Wagner, Y. Amarouchene, D. Bonn, and J. Eggers, Droplet Detachment and Satellite Bead Formation in Viscoelastic Fluids, Physical Review Letters, vol.95, issue.16, p.164504, 2005.
DOI : 10.1103/physrevlett.95.164504
URL : https://hal.archives-ouvertes.fr/hal-01552704

R. M. Weinheimer, D. F. Evans, and E. L. Cussler, Diffusion in surfactant solutions, Journal of Colloid and Interface Science, vol.80, issue.2, p.171, 1981.
DOI : 10.1016/0021-9797(81)90194-6

W. E. Wentworfh, Dependence of the Beer-Lambert absorption law on monochromatic radiation, Journal of Chemical Education, vol.43, p.76, 1966.

, Illinois crop protection technology conference, Basics and benefits of drift control agents, p.14, 2004.

, Le phénomène de dérive constitue un enjeu environnemental et sanitaire majeur lors de la pulvérisation de solutions phytosanitaires sur les surfaces agricoles. Sous l'action du vent, des gouttelettes peuvent dériver loin des champs ciblés et être source de pollution. Une stratégie pour limiter la dérive est de contrôler la distribution de taille des gouttes de spray, Déstabilisation de nappes liquides d'émulsions diluées Abstract

B. Dans-ce, Bien que largement étudiés, les effets de ces émulsions ne sont pas encore bien compris. L'objectif de cette thèse est d'élucider les mécanismes à l'origine de l'augmentation de la taille des gouttes de spray à base d'émulsions. La pulvérisation implique la fragmentation d'un flux de liquide par une buse hydraulique. A la sortie de la buse, une nappe libre de liquide est formée, puis déstabilisée en gouttes. Afin d'élucider les mécanismes à l'origine des effets anti-dérives des émulsions, nous étudions l'influence de ces émulsions sur les mécanismes de déstabilisation des nappes liquides. Une expérience modèle basée sur la collision d'une goutte de solution sur une cible solide est utilisée pour produire et visualiser des nappes liquides. Lors de l'impact, la goutte s'aplatit en une nappe qui s'étend radialement dans l'air, bordée par un bourrelet plus épais. Différents mécanismes de déstabilisation sont observés en fonction des propriétés des fluides, des additifs anti-dérives, tels que des émulsions diluées d'huile dans l'eau, ont été développés

L. Simultanément, . Bourrelet, and . Déstabilisé-en-gouttelettes, Nous constatons que la formation d'un trou dans la nappe est systématiquement précédée par un amincissement local du film liquide. Nous montrons que cet amincissement est le résultat de l'entrée puis de l'étalement par effet Marangoni de gouttelettes d'huile à l'interface air/eau. L'amincissement du film liquide conduit in fine à sa rupture. Nous proposons un mécanisme de perforation en deux étapes: les gouttelettes d'huile (i) entrent à l'interface air/eau, et (ii) s'étalent à l'interface. La formulation de l'émulsion est un paramètre critique pour contrôler le processus de perforation. L'addition de sels ou de copolymères amphiphiles à des émulsions stabilisées par des tensio-actifs ioniques peut soit déclencher, soit inhiber le mécanisme de perforation. Nous montrons que l'entrée de gouttelettes d'huile à l'interface air/eau est l'étape limitante de ce mécanisme, Pour une émulsion diluée d'huile dans l'eau, le mécanisme de déstabilisation dominant est considérablement modifié: les nappes sont déstabilisées par la nucléation de trous qui perforent le film liquide lors de son expansion; les trous grandissent jusqu'à la formation d'un réseau de ligaments, qui est ensuite déstabilisé en gouttes

, Keywords: émulsion huile dans eau, nappe liquide, spray, impact de goutte, effet Marangoni