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Papers by Baptiste Darbois Texier

Research paper thumbnail of Toy geyser experiment: periodicity, operating conditions and coupling

European Journal of Physics

During the embargo period (the 12 month period from the publication of the Version of Record of t... more During the embargo period (the 12 month period from the publication of the Version of Record of this article), the Accepted Manuscript is fully protected by copyright and cannot be reused or reposted elsewhere. As the Version of Record of this article is going to be / has been published on a subscription basis, this Accepted Manuscript is available for reuse under a CC BY-NC-ND 3.0 licence after the 12 month embargo period.

Research paper thumbnail of Optimal propulsion of an undulating slender body with anisotropic friction

Soft matter, Jan 24, 2018

This study investigates theoretically and numerically the propulsive sliding of a slender body. T... more This study investigates theoretically and numerically the propulsive sliding of a slender body. The body sustains a transverse and propagative wave along its main axis, and undergoes anisotropic friction caused by its surface texture sliding on the floor. A model accounting for the anisotropy of frictional forces acting on the body is implemented. This describes the propulsive force and gives the optimal undulating parameters for efficient forward propulsion. The optimal wave characteristics are effectively compared to the undulating motion of a slithering snakes, as well as with the motion of sandfish lizards swimming through the sand. Furthermore, numerical simulations have indicated the existence of certain specialized segments along the body that are highly efficient for propulsion, explaining why snakes lift parts of their body while slithering. Finally, the inefficiency of slithering as a form of locomotion to ascend a slope is discussed.

Research paper thumbnail of Helical Locomotion in a Granular Medium

Research paper thumbnail of On the shape of giant soap bubbles

Proceedings of the National Academy of Sciences of the United States of America, Mar 7, 2017

We study the effect of gravity on giant soap bubbles and show that it becomes dominant above the ... more We study the effect of gravity on giant soap bubbles and show that it becomes dominant above the critical size [Formula: see text], where [Formula: see text] is the mean thickness of the soap film and [Formula: see text] is the capillary length ([Formula: see text] stands for vapor-liquid surface tension, and [Formula: see text] stands for the liquid density). We first show experimentally that large soap bubbles do not retain a spherical shape but flatten when increasing their size. A theoretical model is then developed to account for this effect, predicting the shape based on mechanical equilibrium. In stark contrast to liquid drops, we show that there is no mechanical limit of the height of giant bubble shapes. In practice, the physicochemical constraints imposed by surfactant molecules limit the access to this large asymptotic domain. However, by an exact analogy, it is shown how the giant bubble shapes can be realized by large inflatable structures.

Research paper thumbnail of Low-resistive vibratory penetration in granular media

PloS one, 2017

Non-cohesive materials such as sand, dry snow or cereals are encountered in various common circum... more Non-cohesive materials such as sand, dry snow or cereals are encountered in various common circumstances, from everyday situations to industry. The process of digging into these materials remains a challenge to most animals and machines. Within the animal kingdom, different strategies are employed to overcome this issue, including excavation methods used by ants, the two-anchor strategy employed by soft burrowers such as razor-clams, and undulatory motions exhibited by sandfish lizards. Despite the development of technology to mimic these techniques in diggers and robots, the limitations of animals and machines may differ, and mimicry of natural processes is not necessarily the most efficient technological strategy. This study presents evidence that the resisting force for the penetration of an intruder into a dry granular media can be reduced by one order of magnitude with small amplitude (A ≃ 10 μm) and low frequency (f = 50 - 200 Hz) mechanical vibrations. This observed result is...

Research paper thumbnail of Physics of knuckleballs

New Journal of Physics, 2016

Research paper thumbnail of A capillary Archimedes' screw

Bulletin of the American Physical Society, Nov 23, 2014

Research paper thumbnail of Wicking through a confined micropillar array

Microfluidics and Nanofluidics, 2016

This study considers the spreading of a Newtonian and perfectly wetting liquid in a square array ... more This study considers the spreading of a Newtonian and perfectly wetting liquid in a square array of cylindric micropillars confined between two plates. We show experimentally that the dynamics of the contact line follows a Washburn-like law which depends on the characteristics of the micropillar array (height, diameter and pitch). The presence of pillars can either enhance or slow down the motion of the contact line. A theoretical model based on capillary and viscous forces has been developed in order to rationalize our observations. Finally, the impact of pillars on the volumic flow rate of liquid which is pumped in the microchannel is inspected.

Research paper thumbnail of Are leaves optimally designed for self-support? An investigation on giant monocots

Journal of Theoretical Biology, 2016

Leaves are the organs that intercept light and create photosynthesis. Efficient light interceptio... more Leaves are the organs that intercept light and create photosynthesis. Efficient light interception is provided by leaves oriented orthogonal to most of the sun rays. Except in the polar regions, this means orthogonal to the direction of acceleration due to gravity, or simply horizontal. The leaves of almost all terrestrial plants grow in a gravity field that tends to bend them downward and therefore may counteract light interception. Plants thus allocate biomass for self-support in order to maintain their leaves horizontal. To compete with other species (inter-species competition), as well as other individuals within the same species (intra-species competition), self-support must be achieved with the least biomass produced. This study examines to what extent leaves are designed to self-support. We show here that a basic mechanical model provides the optimal dimensions of a leaf for light interception and self-support. These results are compared to measurements made on leaves of various giant monocot species,especially palm trees and banana trees. The comparison between experiments and model predictions shows that the longer palms are optimally designed for self-support whereas shorter leaves are shaped predominantly by other parameters of selection.

Research paper thumbnail of Video: Leidenfrost impacts on hot liquid baths

68th Annual Meeting of the APS Division of Fluid Dynamics - Gallery of Fluid Motion, 2015

Research paper thumbnail of Deformations of an elastic pipe submitted to gravity and internal fluid flow

Journal of Fluids and Structures, 2015

Research paper thumbnail of Video: Fluid jet guiding

67th Annual Meeting of the APS Division of Fluid Dynamics - Gallery of Fluid Motion, 2014

Research paper thumbnail of Physics of badminton shuttlecocks. Part 1 : aerodynamics

We study experimentally shuttlecocks dynamics. In this part we show that shuttlecock trajectory i... more We study experimentally shuttlecocks dynamics. In this part we show that shuttlecock trajectory is highly different from classical parabola. When one takes into account the aerodynamic drag, the flight of the shuttlecock quickly curves downwards and almost reaches a vertical asymptote. We solve the equation of motion with gravity and drag at high Reynolds number and find an analytical expression of the reach. At high velocity, this reach does not depend on velocity anymore. Even if you develop your muscles you will not manage to launch the shuttlecock very far because of the ``aerodynamic wall.'' As a consequence you can predict the length of the field. We then discuss the extend of the aerodynamic wall to other projectiles like sports balls and its importance.

Research paper thumbnail of The physics of badminton

New Journal of Physics, 2015

The conical shape of a shuttlecock allows it to flip on impact. As a light and extended particle,... more The conical shape of a shuttlecock allows it to flip on impact. As a light and extended particle, it flies with a pure drag trajectory. We first study the flip phenomenon and the dynamics of the flight and then discuss the implications on the game. Lastly, a possible classification of different shots is proposed.

Research paper thumbnail of Toy geyser experiment: periodicity, operating conditions and coupling

European Journal of Physics

During the embargo period (the 12 month period from the publication of the Version of Record of t... more During the embargo period (the 12 month period from the publication of the Version of Record of this article), the Accepted Manuscript is fully protected by copyright and cannot be reused or reposted elsewhere. As the Version of Record of this article is going to be / has been published on a subscription basis, this Accepted Manuscript is available for reuse under a CC BY-NC-ND 3.0 licence after the 12 month embargo period.

Research paper thumbnail of Optimal propulsion of an undulating slender body with anisotropic friction

Soft matter, Jan 24, 2018

This study investigates theoretically and numerically the propulsive sliding of a slender body. T... more This study investigates theoretically and numerically the propulsive sliding of a slender body. The body sustains a transverse and propagative wave along its main axis, and undergoes anisotropic friction caused by its surface texture sliding on the floor. A model accounting for the anisotropy of frictional forces acting on the body is implemented. This describes the propulsive force and gives the optimal undulating parameters for efficient forward propulsion. The optimal wave characteristics are effectively compared to the undulating motion of a slithering snakes, as well as with the motion of sandfish lizards swimming through the sand. Furthermore, numerical simulations have indicated the existence of certain specialized segments along the body that are highly efficient for propulsion, explaining why snakes lift parts of their body while slithering. Finally, the inefficiency of slithering as a form of locomotion to ascend a slope is discussed.

Research paper thumbnail of Helical Locomotion in a Granular Medium

Research paper thumbnail of On the shape of giant soap bubbles

Proceedings of the National Academy of Sciences of the United States of America, Mar 7, 2017

We study the effect of gravity on giant soap bubbles and show that it becomes dominant above the ... more We study the effect of gravity on giant soap bubbles and show that it becomes dominant above the critical size [Formula: see text], where [Formula: see text] is the mean thickness of the soap film and [Formula: see text] is the capillary length ([Formula: see text] stands for vapor-liquid surface tension, and [Formula: see text] stands for the liquid density). We first show experimentally that large soap bubbles do not retain a spherical shape but flatten when increasing their size. A theoretical model is then developed to account for this effect, predicting the shape based on mechanical equilibrium. In stark contrast to liquid drops, we show that there is no mechanical limit of the height of giant bubble shapes. In practice, the physicochemical constraints imposed by surfactant molecules limit the access to this large asymptotic domain. However, by an exact analogy, it is shown how the giant bubble shapes can be realized by large inflatable structures.

Research paper thumbnail of Low-resistive vibratory penetration in granular media

PloS one, 2017

Non-cohesive materials such as sand, dry snow or cereals are encountered in various common circum... more Non-cohesive materials such as sand, dry snow or cereals are encountered in various common circumstances, from everyday situations to industry. The process of digging into these materials remains a challenge to most animals and machines. Within the animal kingdom, different strategies are employed to overcome this issue, including excavation methods used by ants, the two-anchor strategy employed by soft burrowers such as razor-clams, and undulatory motions exhibited by sandfish lizards. Despite the development of technology to mimic these techniques in diggers and robots, the limitations of animals and machines may differ, and mimicry of natural processes is not necessarily the most efficient technological strategy. This study presents evidence that the resisting force for the penetration of an intruder into a dry granular media can be reduced by one order of magnitude with small amplitude (A ≃ 10 μm) and low frequency (f = 50 - 200 Hz) mechanical vibrations. This observed result is...

Research paper thumbnail of Physics of knuckleballs

New Journal of Physics, 2016

Research paper thumbnail of A capillary Archimedes' screw

Bulletin of the American Physical Society, Nov 23, 2014

Research paper thumbnail of Wicking through a confined micropillar array

Microfluidics and Nanofluidics, 2016

This study considers the spreading of a Newtonian and perfectly wetting liquid in a square array ... more This study considers the spreading of a Newtonian and perfectly wetting liquid in a square array of cylindric micropillars confined between two plates. We show experimentally that the dynamics of the contact line follows a Washburn-like law which depends on the characteristics of the micropillar array (height, diameter and pitch). The presence of pillars can either enhance or slow down the motion of the contact line. A theoretical model based on capillary and viscous forces has been developed in order to rationalize our observations. Finally, the impact of pillars on the volumic flow rate of liquid which is pumped in the microchannel is inspected.

Research paper thumbnail of Are leaves optimally designed for self-support? An investigation on giant monocots

Journal of Theoretical Biology, 2016

Leaves are the organs that intercept light and create photosynthesis. Efficient light interceptio... more Leaves are the organs that intercept light and create photosynthesis. Efficient light interception is provided by leaves oriented orthogonal to most of the sun rays. Except in the polar regions, this means orthogonal to the direction of acceleration due to gravity, or simply horizontal. The leaves of almost all terrestrial plants grow in a gravity field that tends to bend them downward and therefore may counteract light interception. Plants thus allocate biomass for self-support in order to maintain their leaves horizontal. To compete with other species (inter-species competition), as well as other individuals within the same species (intra-species competition), self-support must be achieved with the least biomass produced. This study examines to what extent leaves are designed to self-support. We show here that a basic mechanical model provides the optimal dimensions of a leaf for light interception and self-support. These results are compared to measurements made on leaves of various giant monocot species,especially palm trees and banana trees. The comparison between experiments and model predictions shows that the longer palms are optimally designed for self-support whereas shorter leaves are shaped predominantly by other parameters of selection.

Research paper thumbnail of Video: Leidenfrost impacts on hot liquid baths

68th Annual Meeting of the APS Division of Fluid Dynamics - Gallery of Fluid Motion, 2015

Research paper thumbnail of Deformations of an elastic pipe submitted to gravity and internal fluid flow

Journal of Fluids and Structures, 2015

Research paper thumbnail of Video: Fluid jet guiding

67th Annual Meeting of the APS Division of Fluid Dynamics - Gallery of Fluid Motion, 2014

Research paper thumbnail of Physics of badminton shuttlecocks. Part 1 : aerodynamics

We study experimentally shuttlecocks dynamics. In this part we show that shuttlecock trajectory i... more We study experimentally shuttlecocks dynamics. In this part we show that shuttlecock trajectory is highly different from classical parabola. When one takes into account the aerodynamic drag, the flight of the shuttlecock quickly curves downwards and almost reaches a vertical asymptote. We solve the equation of motion with gravity and drag at high Reynolds number and find an analytical expression of the reach. At high velocity, this reach does not depend on velocity anymore. Even if you develop your muscles you will not manage to launch the shuttlecock very far because of the ``aerodynamic wall.'' As a consequence you can predict the length of the field. We then discuss the extend of the aerodynamic wall to other projectiles like sports balls and its importance.

Research paper thumbnail of The physics of badminton

New Journal of Physics, 2015

The conical shape of a shuttlecock allows it to flip on impact. As a light and extended particle,... more The conical shape of a shuttlecock allows it to flip on impact. As a light and extended particle, it flies with a pure drag trajectory. We first study the flip phenomenon and the dynamics of the flight and then discuss the implications on the game. Lastly, a possible classification of different shots is proposed.