Research

Ecosystems’ health and human welfare are inseparably linked to water. In the face of pressing global changes, water resource protection and sustainable management rely on a solid understanding of aquatic systems physics. To support this principle, we strive to develop mechanistic models and mathematical frameworks to characterise the functioning of fluid environments.

Floating Active Carpet in Aquatic Systems

We investigate how communities of swimming microorganisms known as “active carpets” influence their aquatic environment by driving biogenic transport in their surrounding. We combine theory and simulations to examine fundamental metrics, including diffusivity, particle encounters, and particle aggregation. The findings reveal that the hydrodynamic fluctuations generated by active carpets promote particles encounters and aggregation processes. Our study emphasizes the role of biologically driven fluctuations in the transport of essential elements in biogeochemical cycles within aquatic systems. Lear more in the following link:

Transition regimes in confined thermal convection

The phenomenon of thermal convection governs crucial natural and engineered systems, including oceans, hydrothermal systems, and heat exchangers. These systems are all geometrically confined, resulting in restricted convective fluid motions. Our introduction of the “degree of confinement” as a universal parameter characterizes the impact of lateral control on thermal convection, encapsulating fluid properties, system geometry, and thermal forcing. Laboratory experiments demonstrate that the degree of confinement plays a critical role in determining the local and global dynamics of thermal plumes, the fundamental manifestation of convection. Our study connects the classic problem of “Rayleigh–Bénard convection” with various natural and engineering thermo-fluid systems distinguished by their degrees of confinement. For more info and awesome videos, check out the link below:

Convective transport of dissolved gases

The debate over littoral influence on lake gas dynamics persists due to limited quantification of lateral gas transport, as diffusive horizontal transport assumptions fail to explain observed anomalies in pelagic gas concentrations. We reveal, via field experiments, that daily convective horizontal circulation drives significant littoral-pelagic advective gas fluxes, challenging traditional models and emphasizing the need to integrate convective transport into gas budgets in aquatic systems.

Tracking swarms of swimming organisms

Simple and frugal method for tracking occluded self-propelled organisms in densely populated water bodies. We apply the method to monitor swarms of Daphnia Magna in an aquatic laboratory, facilitating the acquisition of comprehensive statistics on swimming behaviours, like flapping frequency and sinking velocity, across a wide range of swimmer sizes.

Stratified Horizontal Convection

Driven by Differential Heating

Laboratory experiments and theory characterizing the fluid dynamics of stratified fluids subject to differential heating at their surface. Learn more:

Convection in Confined Domains

Theoretical, numerical and experimental characterization of thermal and solutal convection in confined domains like faults, fractured media, and porous media. Learn more:

Radiatively Driven Convection

Theory, field and numerical experiments characterising the convective dynamics driven by sunlight in ice-covered waters. Learn more:

Topographically and Thermally Driven

Convective Flows

Characterization of topographically and thermally driven convetive modes of motions in aquatic systems like nearshore waters in seas and lakes. Learn more:

Flows Across Sloping Boundaries

Theory, field and numerical experiments characterising thermally, wind and tidally driven cross-shore flow. Learn more:

Resonance in Enclosed Waterbodies 

Characterization of resonance dynamics of basin-scale interfacial gravity waves induced by wind and modualted by Coriolis acceleration via field, laboratory and numerical studies. Learn more:

Characterization of the dynamic and energy regimes of rotating internal gravity waves in stratified water basins via field, laboratory and numerical experiments. Video: Direct numerical simulation of a Kelvin waves. Learn more:

Hydrodynamics, Mixing and Ecology

of Lakes

Hydrodynamics and mixing in lakes is controlled mainly by wind and heat fluxes. For temperate lakes, deep mixing occurs typically from fall to winter and is one of the essential physical processes supporting the supply of nutrients from deep to near-surface waters and the primary production during the productive season. Modelling the vertical and lateral mass transport is critical to assess the quality of natural waters. Learn more:

Image: Lake Llanquihue, Patagonia, Chile. Video: Numerical simulation of Lagrangian particles in Lake Llanquihue.