A5035427968- Methane Hydrates and Related Phenomena
- Origins and Evolution of Life
- CO2 Sequestration and Geologic Interactions
- Advanced Thermodynamics and Statistical Mechanics
- Wind and Air Flow Studies
- Particle Dynamics in Fluid Flows
- Fluid Dynamics and Turbulent Flows
- Aerodynamics and Acoustics in Jet Flows
- Nonlinear Dynamics and Pattern Formation
- Combustion and Detonation Processes
- Microfluidic and Capillary Electrophoresis Applications
- Heat and Mass Transfer in Porous Media
- Combustion and flame dynamics
- High-pressure geophysics and materials
- Fluid Dynamics and Mixing
- Hydrocarbon exploration and reservoir analysis
- Innovative Microfluidic and Catalytic Techniques Innovation
- Advanced Mathematical Modeling in Engineering
- Photosynthetic Processes and Mechanisms
- Solidification and crystal growth phenomena
- Astro and Planetary Science
- Membrane Separation Technologies
- Atmospheric and Environmental Gas Dynamics
- Photoreceptor and optogenetics research
- Heat Transfer and Optimization
University of Cambridge
2015-2024
Virginia Tech
2017
This work reviews the present position of and surveys future perspectives in physics chaotic advection: field that emerged three decades ago at intersection fluid mechanics nonlinear dynamics, which encompasses a range applications with length scales ranging from micrometers to hundreds kilometers, including systems as diverse mixing thermal processing viscous fluids, microfluidics, biological flows, oceanographic atmospheric flows.
Using scaling, we show that the stability of a buoyant boundary layer in porous medium presence first-order chemical reaction is fully determined by nondimensional number $\mathrm{Da}/{\mathrm{Ra}}^{2}={k}_{r}\mathit{aD}\ensuremath{\phi}{\ensuremath{\mu}}^{2}/(k\ensuremath{\Delta}{\ensuremath{\rho}}_{0}g){}^{2}$, where $\mathrm{Da}={k}_{\mathrm{r}}{\mathit{aL}}_{\mathrm{Z}}^{2}/{k}_{\mathrm{r}}{\mathit{aL}}_{\mathrm{Z}}^{2}(D\ensuremath{\phi})$ Damk\"ohler and...
In order to model ion transport across protocell membranes in Hadean hydrothermal vents, we consider both theoretically and experimentally the planar growth of a precipitate membrane formed at interface between two parallel fluid streams two-dimensional microfluidic reactor. The rate is found be proportional square root time, which characteristic diffusive transport. However, dependence on concentrations hydroxide metal ions approximately linear quadratic, respectively. We show that such...
Self-organizing precipitation processes, such as chemical gardens forming biomimetic micro- and nanotubular forms, have the potential to show us new fundamental science explore, quantify, understand nonequilibrium physicochemical systems, shed light on conditions for life's emergence. The physics chemistry of these phenomena, due assembly material architectures under a flux ions, their exploitation in applications, recently been termed chemobrionics. Advances understanding this area require...
The stability of an immiscible layer fluid bounded by two other fluids different viscosities and migrating through a porous medium is analysed, both theoretically experimentally. Linear analyses for one-dimensional radial flows are presented, with particular emphasis upon the behaviour when one interfaces highly stable unstable. For motion, it found that owing to unstable interface, intermediate eventually breaks up into drops. However, in case flow, surface tension continuous thinning as...
Black smokers and Lost City-type springs are varieties of hydrothermal vents on the ocean floors that emit hot, acidic water cool, alkaline water, respectively. While both produce precipitation structures as issuing fluid encounters oceanic in particular have been implicated origin life Earth. We present a parallel-velocity flow model for radius rate cylindrical jet forms template growth tube precipitated about itself we compare solution with previous laboratory experimental results from...
An experimental and theoretical study of the mixing produced by a plume rising in confined stratified environment is presented. As result pre-existing stable stratification, penetrates only part way into region; at an intermediate level it intrudes laterally forming horizontal layer. time evolves, this layer mixed fluid observed to increase thickness. The bottom front advects downward analogous first filling box Baines & Turner (1969), while lateral spreading occurs ever-increasing...
We study numerically the nonlinear interactions between chemical reaction and convective fingering in a diffusive boundary layer porous medium. The enhances stability by consuming solute that is unstably distributed gravitational field. show profoundly changes dynamics of system, introducing steady state, shortening evolution time, altering spatial patterns velocity concentration solute. In presence weak reaction, finger growth merger occur effectively, driving strong currents thick However,...
Abstract The Strytan Hydrothermal Field (SHF) in basaltic terrain Iceland is one of the extant alkaline submarine hydrothermal vent systems favoured as analogues for where life on Earth may have begun. To test this hypothesis we analyse composition, structure, and mineralogy samples from chimneys generated at SHF. We find that chimney precipitates are composed Mg-silicates including clays saponite-stevensite group (high Mg Si, low Fe Al), Ca-carbonates Ca-sulfates. comprise permeable...
Two reaction systems that are at first sight very different produce similar macroscopic filamentary product trails. The chemical gardens confined to a Hele-Shaw cell and corroding metal plates undergo filiform corrosion. We show the two in fact much alike. Our experiments analysis filament dynamics obey scaling laws both instances: motion is nearly ballistic fully self-avoiding, which creates self-trapping events.
Experimental study of the destabilising hydrodynamic effect a second-order chemical reaction in an immiscible system.
We describe new experiments in which a bubble plume, produced from point source of bubbles, rises through an ambient fluid composed two layers different density. In the lower layer, speed plume exceeds rise and motion is well described using classical theory turbulent buoyant plumes. As mixture enters upper it either to top or negatively forms fountain. our experiments, fountain characteristic this fountain, separated flow develops. The bubbles system, while layer finite distance into...
We quantify the destabilising effect of a first-order chemical reaction on fingering instability diffusive boundary layer in porous medium. Using scaling, we show that dynamics such reactive is fully determined by two dimensionless groups: Da/Ra2, which measures timescale for convection compared to those and diffusion; βC/βA, reflects density change induced product relative diffusing solute. Linear stability numerical results βC/βA range 0-10 Da/Ra2 0-0.01 are presented. It shown increases...
Modelling describes oscillatory dynamics of precipitate filaments; growth an ensemble filaments is a self-organized dispersion mechanism.
A new way of ascertaining whether or not a reacting mixture will explode uses just three timescales: that for chemical reaction to heat up the fluid containing reactants and products, timescale conduction out reactor, natural convection in fluid. This approach is developed an nth order reaction, → B occurring exothermically spherical, batch reactor without significant consumption A. The timescales are expressed terms physical parameters system. Numerical simulations performed laminar...