A5080181781- Biomimetic flight and propulsion mechanisms
- Lattice Boltzmann Simulation Studies
- Marine Invertebrate Physiology and Ecology
- Micro and Nano Robotics
- Seismic Imaging and Inversion Techniques
- Seismic Waves and Analysis
- Fluid Dynamics and Turbulent Flows
- Cardiovascular Function and Risk Factors
- Image and Signal Denoising Methods
- Fluid Dynamics and Vibration Analysis
- Cardiomyopathy and Myosin Studies
- Coral and Marine Ecosystems Studies
- Congenital heart defects research
- Fluid Dynamics Simulations and Interactions
- Vibration and Dynamic Analysis
- Insect and Arachnid Ecology and Behavior
- Soil Moisture and Remote Sensing
- Physiological and biochemical adaptations
- Hydrology and Sediment Transport Processes
- Fluid Dynamics and Heat Transfer
- Underwater Vehicles and Communication Systems
- Aeolian processes and effects
- Tree Root and Stability Studies
- Cephalopods and Marine Biology
- Zebrafish Biomedical Research Applications
University of Arizona
2020-2024
University of Glasgow
2024
University of Illinois Urbana-Champaign
2024
University of Maine
2023
University of North Carolina at Chapel Hill
2011-2020
United States Air Force
2019
Worcester Polytechnic Institute
2014
North Carolina State University
2012
New York University
2004-2009
Courant Institute of Mathematical Sciences
2004-2009
SUMMARY In this paper, we have used the immersed boundary method to solve two-dimensional Navier–Stokes equations for two wings performing an idealized `clap and fling' stroke a `fling' half-stroke. We calculated lift coefficients as functions of time per wing range Reynolds numbers (Re) between 8 128. also instantaneous streamlines around each throughout cycle related changes in relative strength position leading trailing edge vortices. Our results show that generation during fling'of when...
SUMMARY Of the insects that have been filmed in flight, those are 1 mm length or less often clap their wings together at end of each upstroke and fling them apart beginning downstroke. This `clap fling'motion is thought to augment lift forces generated during flight. What has not highlighted previous work very large required low Reynolds numbers relevant these tiny insects. In this paper, we use immersed boundary method simulate rigid flexible wings. We find drag with can be up 10 times...
The upside-down jellyfish Cassiopea xamachana (Scyphozoa: Rhizostomeae) has been predominantly studied to understand its interaction with the endosymbiotic dinoflagellate algae Symbiodinium. As an easily culturable and tractable cnidarian model, it is attractive alternative stony corals understanding mechanisms driving establishment maintenance of symbiosis. also unique in requiring symbiont order complete transition adult stage, thereby providing excellent model symbiosis-driven development...
We have used computational fluid dynamics to study changes in lift generation and vortex for Reynolds numbers (Re) between 8 128. The immersed boundary method was model a two-dimensional wing through one stroke cycle. calculated drag coefficients as function of time related the shedding or attachment leading trailing edge vortices. find that around fall into two distinct patterns. For Re> =64, vortices are alternately shed behind wing, forming von Karman street. Re< =32, remain attached...
The aerodynamics of flapping flight for the smallest insects such as thrips is often characterized by a 'clap and fling' wings at end upstroke beginning downstroke. These fly Reynolds numbers (Re) order 10 or less where viscous effects are significant. Although this wing motion known to augment lift generated during flight, drag required fling apart scale an magnitude larger than corresponding force acting on single wing. As opposing forces normal each nearly cancel fling, these large do not...
The smallest flying insects commonly possess wings with long bristles. Little quantitative information is available on the morphology of these bristles, and their functional importance remains a mystery. In this study, we (1) collected morphological data bristles 23 species Mymaridae by analyzing high-resolution photographs (2) used immersed boundary method to determine via numerical simulation whether bristled reduced force required fling apart while still maintaining lift. effects Reynolds...
In many swimming and flying animals, propulsion emerges from the interplay of active muscle contraction, passive body elasticity fluid–body interaction. Changes in properties can influence performance cost transport across a broad range scales; they specifically affect vortex generation that is crucial for effective at higher Reynolds numbers. Theoretical models account both contraction are needed to understand how animals tune their move efficiently through fluids. This particularly...
The development of fluid-structure interaction (FSI) software involves trade-offs between ease use, generality, performance, and cost.Typically there are large learning curves when using low-level to model the an elastic structure immersed in a uniform density fluid.Many existing codes not publicly available, commercial that exists usually requires expensive licenses may be as robust or allow necessary flexibility house can provide.We present open source boundary package, IB2d, with full...
Abstract We use computer simulations and an analytical model to study the relationship between kinematics performance in jet-propelled jellyfish swimming. prescribe different power-law for bell contraction expansion, identify that yield high swimming speeds and/or efficiency. In simulations, efficiency is found when radius a nearly linear function of time, second case corresponding ‘burst-and-coast’ kinematics. The studies phase only, finds efficiency-optimizing as time transitions from...
Here we review recent contributions to the study of insect flight, in particular those brought about by advances experimental techniques. We focus particularly on following areas: wing flexibility and deformation, physiology biophysics asynchronous flight muscle, aerodynamics stability maneuverability. This research reveals importance provides a detailed model how muscle functions it may have evolved, synthesizes many studies into broad-reaching summary unsteady aerodynamics, highlights new...
This article provides models and code for numerically simulating muscle-fluid-structure interactions (FSIs). work was presented as part of the symposium on Leading Students Faculty to Quantitative Biology through Active Learning at society-wide meeting Society Integrative Comparative in 2015. Muscle mechanics simple mathematical describe forces generated by muscular contractions are introduced most biomechanics physiology courses. Often, however, derived simplifying cases such isometric or...
Mathematical and experimental studies of the flows generated by jellyfish have focused primarily on mechanisms swimming. More recent work has also considered fluid dynamics feeding from currents during Here we capitalize benthic lifestyle upside-down (Cassiopea xamachana) to explore uncoupled A two-dimensional mathematical model is developed capture fundamental characteristics motion unique concave bell shape. Given prominence oral arms, this structure included modeled as a porous layer that...
Flexible plants, fungi and sessile animals reconfigure in wind water to reduce the drag acting upon them. In strong winds flood waters, for example, leaves roll up into cone shapes that compared with rigid objects of similar surface area. Less understood is how a leaf attached flexible stalk will stably an unsteady flow. Previous mathematical physical models have only considered case sheet tether steady this paper, dynamics flow around wild ginger Hexastylis arifolia violet Viola...
SUMMARY Quantifying the flows generated by pulsations of jellyfish bells is crucial for understanding mechanics and efficiency their swimming feeding. Recent experimental theoretical work has focused on dynamics vortices in wakes with relatively simple oral arms tentacles. The significance bell generating feeding currents through elaborate consequences particle capture are not as well understood. To isolate generation from swimming, pulsing kinematics fluid flow around benthic Cassiopea spp....
Diverse organisms that swim and fly in the inertial regime use flapping or pumping of flexible appendages cavities to propel themselves through a fluid. It has long been postulated speed efficiency locomotion are optimized by oscillating these at their frequency free vibration. In jellyfish swimming, significant contribution locomotory attributed effects passive energy recapture, whereby bell is passively propelled fluid its interaction with stopping vortex rings formed during each expansion...
Significance Despite a relatively simple nervous system, jellyfish manage broad range of motion from distributed set pacemakers, which initiate action potentials that form wave muscular activation to drive the bell motion. In this interdisciplinary study, we find successful turning maneuvers are dependent on speed wave. Using three-dimensional computational fluid–structure interaction model, demonstrate setting near bell’s material speed, elastic equation, yields strongest and margin...
In contrast to larger species, little is known about the flight of smallest flying insects, such as thrips and fairyflies. These tiny animals range from 300 1000 microns in length fly at Reynolds numbers ranging 4 60. Previous work with numerical physical models have shown that aerodynamics these diminutive insects significantly different animals, but most studies relied on two-dimensional approximations. There can, however, be significant differences between two- three-dimensional flows,...