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Articles 61 - 90 of 283
Full-Text Articles in Physics
Giant Magnetization Canting Due To Symmetry Breaking In Zigzag Co Chains On Ir(001), B. Dupé, Jessica E. Bickel, Y. Mokrousov, F. Otte, Kirsten Von Bergmann, André Kubetzka, Stefan Heinze, Roland Wiesendanger
Giant Magnetization Canting Due To Symmetry Breaking In Zigzag Co Chains On Ir(001), B. Dupé, Jessica E. Bickel, Y. Mokrousov, F. Otte, Kirsten Von Bergmann, André Kubetzka, Stefan Heinze, Roland Wiesendanger
Physics Faculty Publications
We demonstrate a canted magnetization of biatomic zigzag Co chains grown on the (5 × 1) reconstructed Ir(001) surface using density functional theory (DFT) calculations and spin-polarized scanning tunneling microscopy (SP-STM) experiments. It is observed by STM that biatomic Co chains grow in three different structural configurations. Our DFT calculations show that they are all in a ferromagnetic (FM) state. Two chain types possess high symmetry due to two equivalent atomic strands and an easy magnetization direction that is along one of the principal crystallographic axes. The easy magnetization axis of the zigzag Co chains is canted away from the …
Fluctuations In A Quasi-Stationary Shallow Cumulus Cloud Ensemble, M. Sakradzija, Axel Seifert, Thijs Heus
Fluctuations In A Quasi-Stationary Shallow Cumulus Cloud Ensemble, M. Sakradzija, Axel Seifert, Thijs Heus
Physics Faculty Publications
We propose an approach to stochastic parameterisation of shallow cumulus clouds to represent the convective variability and its dependence on the model resolution. To collect information about the individual cloud lifecycles and the cloud ensemble as a whole, we employ a large eddy simulation (LES) model and a cloud tracking algorithm, followed by conditional sampling of clouds at the cloud-base level. In the case of a shallow cumulus ensemble, the cloud-base mass flux distribution is bimodal, due to the different shallow cloud subtypes, active and passive clouds. Each distribution mode can be approximated using a Weibull distribution, which is a …
Use Of Grooved Microchannels To Improve The Performance Of Membrane-Less Fuel Cells, J. D'Alessandro, Petru S. Fodor
Use Of Grooved Microchannels To Improve The Performance Of Membrane-Less Fuel Cells, J. D'Alessandro, Petru S. Fodor
Physics Faculty Publications
In this work, the fluid dynamics within a membrane-less microchannel fuel cell is analyzed computationally. The membrane-less design is a result of the laminar nature of the fluid flow at small Reynolds numbers, restricting the fuel and oxidant to the vicinity of the corresponding electrodes, without the need of a proton exchange membrane (PEM). However, the performance of such cells is limited by the slow diffusive mass transport near the electrodes, with a large fraction of the reactants leaving the channel without coming in contact with the catalytic surfaces, and thus not being used. We mitigate this problem through the …
Measurements Of Turbulent Mixing And Subsiding Shells In Trade Wind Cumuli, Jeannine Katzwinkel, Holger Siebert, Thijs Heus, Raymond A. Shaw
Measurements Of Turbulent Mixing And Subsiding Shells In Trade Wind Cumuli, Jeannine Katzwinkel, Holger Siebert, Thijs Heus, Raymond A. Shaw
Physics Faculty Publications
High-resolution measurements of the turbulent, thermodynamic, and microphysical structure of the edges of trade wind cumuli have been performed with the Airborne Cloud Turbulence Observation System. Lateral entrainment of subsaturated air into the cloud region leads to an evaporative cooling effect. The negatively buoyant air partly enhances the compensating downdraft, forming a subsiding shell at cloud edge. Based on the presented observations, the subsiding shell is divided into a turbulent and humid inner shell adjacent to the cloud interior and a nonbuoyant, nonturbulent outer shell. In the trade wind region, continuous development of shallow cumuli over the day allows for …
Near Real-Time Measurement Of Forces Applied By An Optical Trap To A Rigid Cylindrical Object, Joseph Glaser, David Hoeprich, Andrew Resnick
Near Real-Time Measurement Of Forces Applied By An Optical Trap To A Rigid Cylindrical Object, Joseph Glaser, David Hoeprich, Andrew Resnick
Physics Faculty Publications
An automated data acquisition and processing system is established to measure the force applied by an optical trap to an object of unknown composition in real time. Optical traps have been in use for the past 40 years to manipulate microscopic particles, but the magnitude of applied force is often unknown and requires extensive instrument characterization. Measuring or calculating the force applied by an optical trap to nonspherical particles presents additional difficulties which are also overcome with our system. Extensive experiments and measurements using well-characterized objects were performed to verify the system performance.
The Impact Of The Initial Surface Reconstruction On Heteroepitaxial Film Growth And Defect Formation, Jessica E. Bickel, Joanna Mirecki Millunchick
The Impact Of The Initial Surface Reconstruction On Heteroepitaxial Film Growth And Defect Formation, Jessica E. Bickel, Joanna Mirecki Millunchick
Physics Faculty Publications
While it is well known that growth conditions such as temperature greatly affect defect incorporation in thin films, less is known about the direct effects of the surface reconstruction. In this work, we examine the effect of the initial surface reconstruction on defect incorporation in GaSb/GaAs(001) lattice mismatched films. The stress built up in GaSb films grown on As-terminated and Sb-terminated GaAs was monitored during film growth and shows that the total relaxation is similar in both films along the [110], but lower on the Sb-terminated surface along the . These differences can be understood by examining the ability for …
Detection And Antibiotic Treatment Of Mycoplasma Arginini Contamination In A Mouse Epithelial Cell Line Restore Normal Cell Physiology, Brianna Boslett, Subhra Nag, Andrew Resnick
Detection And Antibiotic Treatment Of Mycoplasma Arginini Contamination In A Mouse Epithelial Cell Line Restore Normal Cell Physiology, Brianna Boslett, Subhra Nag, Andrew Resnick
Physics Faculty Publications
Mycoplasma contamination of cultured cell lines is difficult to detect by routine observation. Infected cells can display normal morphology and the slow growth rate of mycoplasma can delay detection for extended periods of time, compromising experimental results. Positive identification of mycoplasma typically requires cells to be either fixed and stained for DNA or processed with PCR. We present a method to detect mycoplasma using live-cell optical microscopy typically used for routine observation of cell cultures. Images of untreated mycoplasma-infected epithelial cells alongside images of infected cells treated with Plasmocin, a commercially available antibiotic targeted to mycoplasma, are shown. We found …
The Creation Of 360° Domain Walls In Ferromagnetic Nanorings By Circular Applied Magnetic Fields, Jessica E. Bickel, Spencer A. Smith, Katherine E. Aidala
The Creation Of 360° Domain Walls In Ferromagnetic Nanorings By Circular Applied Magnetic Fields, Jessica E. Bickel, Spencer A. Smith, Katherine E. Aidala
Physics Faculty Publications
Switching behavior in ferromagnetic nanostructures is often determined by the formation and annihilation of domain walls (DWs). In contrast to the more familiar 180° DWs found in most nanostructures, 360° DWs are the proposed transition state of nanorings. This paper examines the formation of 360° DWs created by the application of a circular magnetic field using micromagnetic simulations. 360° DWs form from pairs of canting moments that are oppositely aligned, which each grow to form rotated domains bounded by two 180° DWs and the 180° DWs combine to form 360° DWs. The resulting 360° DWs occur in pairs of opposite …
Writing And Deleting Single Magnetic Skyrmions, Niklas Romming, Christian Hanneken, Matthias Menzel, Jessica E. Bickel, Boris Wolter, Kirsten Von Bergmann, André Kubetzka, Roland Wiesendanger
Writing And Deleting Single Magnetic Skyrmions, Niklas Romming, Christian Hanneken, Matthias Menzel, Jessica E. Bickel, Boris Wolter, Kirsten Von Bergmann, André Kubetzka, Roland Wiesendanger
Physics Faculty Publications
Topologically nontrivial spin textures have recently been investigated for spintronic applications. Here, we report on an ultrathin magnetic film in which individual skyrmions can be written and deleted in a controlled fashion with local spin-polarized currents from a scanning tunneling microscope. An external magnetic field is used to tune the energy landscape, and the temperature is adjusted to prevent thermally activated switching between topologically distinct states. Switching rate and direction can then be controlled by the parameters used for current injection. The creation and annihilation of individual magnetic skyrmions demonstrates the potential for topological charge in future information-storage concepts.
Automated Tracking Of Shallow Cumulus Clouds In Large Domain, Long Duration Large Eddy Simulations, Thijs Heus, Axel Seifert
Automated Tracking Of Shallow Cumulus Clouds In Large Domain, Long Duration Large Eddy Simulations, Thijs Heus, Axel Seifert
Physics Faculty Publications
This paper presents a method for feature tracking of fields of shallow cumulus convection in large eddy simulations (LES) by connecting the projected cloud cover in space and time, and by accounting for splitting and merging of cloud objects. Existing methods tend to be either imprecise or, when using the full three-dimensional (3-D) spatial field, prohibitively expensive for large data sets. Compared to those 3-D methods, the current method reduces the memory footprint by up to a factor 100, while retaining most of the precision by correcting for splitting and merging events between different clouds. The precision of the algorithm …
Direct Numerical Simulation Of Evaporative Cooling At The Lateral Boundary Of Shallow Cumulus Clouds, Dick Abma, Thijs Heus, Juan Pedro Mellado
Direct Numerical Simulation Of Evaporative Cooling At The Lateral Boundary Of Shallow Cumulus Clouds, Dick Abma, Thijs Heus, Juan Pedro Mellado
Physics Faculty Publications
This study investigates the dynamics of the subsiding shell at the lateral boundary of cumulus clouds, focusing on the role of evaporative cooling. Since the size of this shell is well below what large-eddy simulations can resolve, the authors have performed direct numerical simulations of an idealized subsiding shell. The system develops a self-similar, Reynolds number–independent flow that allows for the determination of explicit scaling laws relating the characteristic length, time, and velocity scales of the shell. It is found that the shell width grows quadratically in time, linearly with the traveled distance. The magnitude of these growth rates shows …
Visco-Elastic Properties Of Duct Tape, Ashley Brown, Ulrich Zurcher
Visco-Elastic Properties Of Duct Tape, Ashley Brown, Ulrich Zurcher
Physics Faculty Publications
A simple experiment for determining the nonlinear stress–strain relation of duct tape is described. After weights are added and subsequently removed, the tape does not return to its original state and is no longer taut. The tape exhibits hysteresis, which implies the loss of work during the cyclical process. The exponent describing the nonlinearity is related to the fractional work loss.
Large-Eddy Simulation Of Organized Precipitating Trade Wind Cumulus Clouds, Axel Seifert, Thijs Heus
Large-Eddy Simulation Of Organized Precipitating Trade Wind Cumulus Clouds, Axel Seifert, Thijs Heus
Physics Faculty Publications
Trade wind cumulus clouds often organize in along-wind cloud streets and across-wind mesoscale arcs. We present a benchmark large-eddy simulation which resolves the individual clouds as well as the mesoscale organization on scales of O(10 km). Different methods to quantify organization of cloud fields are applied and discussed. Using perturbed physics large-eddy simulation experiments, the processes leading to the formation of cloud clusters and the mesoscale arcs are revealed. We find that both cold pools as well as the sub-cloud layer moisture field are crucial to understand the organization of precipitating shallow convection. Further sensitivity studies show that microphysical assumptions …
Marine Low Cloud Sensitivity To An Idealized Climate Change: The Cgils Les Intercomparison, Peter N. Blossey, Christopher S. Bretherton, Minghua Zhang, Anning Cheng, Satoshi Endo, Thijs Heus, Yangang Liu, Adrian P. Lock, Stephan R. De Roode, Kuan Man Xu
Marine Low Cloud Sensitivity To An Idealized Climate Change: The Cgils Les Intercomparison, Peter N. Blossey, Christopher S. Bretherton, Minghua Zhang, Anning Cheng, Satoshi Endo, Thijs Heus, Yangang Liu, Adrian P. Lock, Stephan R. De Roode, Kuan Man Xu
Physics Faculty Publications
Subtropical marine low cloud sensitivity to an idealized climate change is compared in six large-eddy simulation (LES) models as part of CGILS. July cloud cover is simulated at three locations over the subtropical northeast Pacific Ocean, which are typified by cold sea surface temperatures (SSTs) under well-mixed stratocumulus, cool SSTs under decoupled stratocumulus, and shallow cumulus clouds overlying warmer SSTs. The idealized climate change includes a uniform 2 K SST increase with corresponding moist-adiabatic warming aloft and subsidence changes, but no change in free-tropospheric relative humidity, surface wind speed, or CO2. For each case, realistic advective forcings and boundary conditions …
Cgils: Results From The First Phase Of An International Project To Understand The Physical Mechanisms Of Low Cloud Feedbacks In Single Column Models, Minghua Zhang, Christopher S. Bretherton, Peter N. Blossey, Phillip H. Austin, Julio T. Bacmeister, Sandrine Bony, Florent Brient, Suvarchal K. Cheedela, Anning Cheng, Anthony D. Del Genio, Stephan R. De Roode, Satoshi Endo, Charmaine N. Franklin, Jean Christophe Golaz, Cecile Hannay, Thijs Heus
Cgils: Results From The First Phase Of An International Project To Understand The Physical Mechanisms Of Low Cloud Feedbacks In Single Column Models, Minghua Zhang, Christopher S. Bretherton, Peter N. Blossey, Phillip H. Austin, Julio T. Bacmeister, Sandrine Bony, Florent Brient, Suvarchal K. Cheedela, Anning Cheng, Anthony D. Del Genio, Stephan R. De Roode, Satoshi Endo, Charmaine N. Franklin, Jean Christophe Golaz, Cecile Hannay, Thijs Heus
Physics Faculty Publications
CGILS—the CFMIP-GASS Intercomparison of Large Eddy Models (LESs) and single column models (SCMs)—investigates the mechanisms of cloud feedback in SCMs and LESs under idealized climate change perturbation. This paper describes the CGILS results from 15 SCMs and 8 LES models. Three cloud regimes over the subtropical oceans are studied: shallow cumulus, cumulus under stratocumulus, and well-mixed coastal stratus/stratocumulus. In the stratocumulus and coastal stratus regimes, SCMs without activated shallow convection generally simulated negative cloud feedbacks, while models with active shallow convection generally simulated positive cloud feedbacks. In the shallow cumulus alone regime, this relationship is less clear, likely due to …
Extending Newton’S Apsidal Theorem: Effective Angular Momentum, Cameron J. Tuckerman
Extending Newton’S Apsidal Theorem: Effective Angular Momentum, Cameron J. Tuckerman
Undergraduate Research Posters 2012
Apsidal Shift, or the angular displacement of the orbital apses, is an important quantity in the study of the orbits of planets, starts, and other celestial bodies. The apparent lack of shift of our nearby planets is that on which Sir Isaac Newton based his assumption of the inverse-square relationship in Universal Gravity. We are able to find excellent approximations for the Apsidal Shift and use our results to generalize Newton's Apsidal Theorem.
Light Scattering Study Of Elongated Particles: From Inorganic Nanorice To Polypeptide Micelles, Philip Dee
Light Scattering Study Of Elongated Particles: From Inorganic Nanorice To Polypeptide Micelles, Philip Dee
Undergraduate Research Posters 2012
Utilizing the powerful experimental technique of Dynamic Light Scattering (DLS) for size characterization of anisotropic particles can be extremely misleading. Unfortunately, this point is often not realized by researchers who strive for particle sizing of nanoparticles in suspensions. We present a consistent analysis of DDLS results on FeOOH nanorice and outline the potential difficulties and challenges of DDLS application for polypeptide micelles.
Continuous Single-Column Model Evaluation At A Permanent Meteorological Supersite, Roel A.J. Neggers, A. Pier Siebesma, Thijs Heus
Continuous Single-Column Model Evaluation At A Permanent Meteorological Supersite, Roel A.J. Neggers, A. Pier Siebesma, Thijs Heus
Physics Faculty Publications
Uncertainties in numerical predictions of weather and climate are often linked to the representation of unresolved processes that act relatively quickly compared to the resolved general circulation. These processes include turbulence, convection, clouds, and radiation. Single-column model (SCM) simulation of idealized cases and the subsequent evaluation against large-eddy simulation (LES) results has become an often used and relied on method to obtain insight at process level into the behavior of such parameterization schemes; benefits of SCM simulation are the enhanced model transparency and the high computational efficiency. Although this approach has achieved demonstrable success, some shortcomings have been identified; among …
Geometric Constructions For Image Formation By A Converging Lens, Ulrich Zürcher
Geometric Constructions For Image Formation By A Converging Lens, Ulrich Zürcher
Physics Faculty Publications
Light rays emerge from an object in all directions. In introductory texts, three 'special' rays are selected to draw the image produced by lenses and mirrors. This presentation may suggest to students that these three rays are necessary for the formation of an image. We discuss that the three rays attain their 'special status' from the geometric solution of the equation of a hyperbola x−1 + y−1 = c−1 (mirror/lens equation). The material is suitable for use in introductory courses for science majors.
Information Transfer By Vector Spin Chirality In Finite Magnetic Chains, Matthias Menzel, Yuriy Mokrousov, Robert Wieser, Jessica E. Bickel, Elena Vedmedenko, Stefan Blügel, Stefan Heinze, Kirsten Von Bergmann, André Kubetzka, Roland Wiesendanger
Information Transfer By Vector Spin Chirality In Finite Magnetic Chains, Matthias Menzel, Yuriy Mokrousov, Robert Wieser, Jessica E. Bickel, Elena Vedmedenko, Stefan Blügel, Stefan Heinze, Kirsten Von Bergmann, André Kubetzka, Roland Wiesendanger
Physics Faculty Publications
Vector spin chirality is one of the fundamental characteristics of complex magnets. For a one-dimensional spin-spiral state it can be interpreted as the handedness, or rotational sense of the spiral. Here, using spin-polarized scanning tunneling microscopy, we demonstrate the occurrence of an atomic-scale spin spiral in finite individual bi-atomic Fe chains on the (5×1)−Ir(001) surface. We show that the broken inversion symmetry at the surface promotes one direction of the vector spin chirality, leading to a unique rotational sense of the spiral in all chains. Correspondingly, changes in the spin direction of one chain end can be probed tens of …
Overlap Statistics Of Cumuliform Boundary-Layer Cloud Fields In Large-Eddy Simulations, Roel A.J. Neggers, Thijs Heus, A. Pier Siebesma
Overlap Statistics Of Cumuliform Boundary-Layer Cloud Fields In Large-Eddy Simulations, Roel A.J. Neggers, Thijs Heus, A. Pier Siebesma
Physics Faculty Publications
Overlap statistics of cumuliform boundary-layer clouds are studied using large-eddy simulations at high resolutions. The cloud overlap is found to be highly inefficient, due to the typical irregularity of cumuliform clouds over a wide range of scales. The detection of such inefficient overlap is enabled in this study by i) applying fine enough discretizations and ii) by limiting the analysis to exclusively cumuliform boundary-layer cloud fields. It is argued that these two factors explain the differences with some previous studies on cloud overlap. In contrast, good agreement exists with previously reported observations of cloud overlap as derived from lidar measurements …
Equation Of State From The Potts-Percolation Model Of A Solid, Miron Kaufman
Equation Of State From The Potts-Percolation Model Of A Solid, Miron Kaufman
Physics Faculty Publications
We expand the Potts-percolation model of a solid to include stress and strain. Neighboring atoms are connected by bonds. We set the energy of a bond to be given by the Lennard-Jones potential. If the energy is larger than a threshold the bond is more likely to fail, whereas if the energy is lower than the threshold, the bond is more likely to be alive. In two dimensions we compute the equation of state: stress as a function of interatomic distance and temperature by using renormalization-group and Monte Carlo simulations. The phase diagram, the equation of state, and the isothermal …
Chronic Fluid Flow Is An Environmental Modifier Of Renal Epithelial Function, Andrew Resnick
Chronic Fluid Flow Is An Environmental Modifier Of Renal Epithelial Function, Andrew Resnick
Physics Faculty Publications
Although solitary or sensory cilia are present in most cells of the body and their existence has been known since the sixties, very little is been known about their functions. One suspected function is fluid flow sensing- physical bending of cilia produces an influx of Ca++, which can then result in a variety of activated signaling pathways. Autosomal Dominant Polycystic Kidney Disease (ADPKD) is a progressive disease, typically appearing in the 5th decade of life and is one of the most common monogenetic inherited human diseases, affecting approximately 600,000 people in the United States. Because ADPKD is a slowly progressing …
Glitter And Glints On Water, David K. Lynch, David S. P. Dearborn, James A. Lock
Glitter And Glints On Water, David K. Lynch, David S. P. Dearborn, James A. Lock
Physics Faculty Publications
We present new observations of glitter and glints using short and long time exposure photographs and high frame rate videos. Using the sun and moon as light sources to illuminate the ocean and laboratory water basins, we found that (1) most glitter takes place on capillary waves rather than on gravity waves, (2) certain aspects of glitter morphology depend on the presence or absence of thin clouds between the light source and the water, and (3) bent glitter paths are caused by asymmetric wave slope distributions We present computer simulations that are able to reproduce the observations and make predictions …
Magnetic Properties Of Monolayer Co Islands On Ir(111) Probed By Spin-Resolved Scanning Tunneling Microscopy, Jessica E. Bickel, Focko Meier, Jens Brede, André Kubetzka, Kirsten Von Bergmann, Roland Wiesendanger
Magnetic Properties Of Monolayer Co Islands On Ir(111) Probed By Spin-Resolved Scanning Tunneling Microscopy, Jessica E. Bickel, Focko Meier, Jens Brede, André Kubetzka, Kirsten Von Bergmann, Roland Wiesendanger
Physics Faculty Publications
As the characteristic length scale of devices continues to decrease, it is essential to understand the fundamental magnetic properties of reduced dimension structures. This paper examines the electronic and magnetic properties of two-dimensional nanoscale Co islands on an Ir(111) surface using spin-polarized scanning tunneling microscopy. The pseudomorphic Co islands investigated are ferromagnetic and single domain, with the magnetic easy axis normal to the sample surface. Remarkably, the coercivity of these islands is greater than 4 T and magnetic saturation of the islands requires an applied field of at least 5 T.
Mie Scattering In The Time Domain. Part I. The Role Of Surface Waves, James A. Lock, Philip Laven
Mie Scattering In The Time Domain. Part I. The Role Of Surface Waves, James A. Lock, Philip Laven
Physics Faculty Publications
We computed the Debye series p = 1 and p = 2 terms of the Mie scattered intensity as a function of scattering angle and delay time for a linearly polarized plane wave pulse incident on a spherical dielectric particle and physically interpreted the resulting numerical data. Radiation shed by electromagnetic surface waves plays a prominent role in the scattered intensity. We determined the surface wave phase and damping rate and studied the structure of the p = 1, 2 surface wave glory in the time domain. (C) 2011 Optical Society of America
Mie Scattering In The Time Domain. Part Ii. The Role Of Diffraction, James A. Lock, Philip Laven
Mie Scattering In The Time Domain. Part Ii. The Role Of Diffraction, James A. Lock, Philip Laven
Physics Faculty Publications
The p = 0 term of the Mie-Debye scattering amplitude contains the effects of external reflection and diffraction. We computed the reflected intensity in the time domain as a function of the scattering angle and delay time for a short electromagnetic pulse incident on a spherical particle and compared it to the predicted behavior in the forward-focusing region, the specular reflection region, and the glory region. We examined the physical consequences of three different approaches to the exact diffraction amplitude, and determined the signature of diffraction in the time domain. The external reflection surface wave amplitude gradually replaces the diffraction …
Radial Motion In A Central Potential For Singular Mass Densities, Ulrich Zürcher, Miron Kaufman
Radial Motion In A Central Potential For Singular Mass Densities, Ulrich Zürcher, Miron Kaufman
Physics Faculty Publications
We study the radial motion of an object in the gravitational field produced by an isotropic mass density that is singular at the origin. This problem applies to elliptical galaxies and can be used to illustrate motion in a central field appropriate for an intermediate-level mechanics course.
Torque Around The Center Of Mass: Dynamic Stability During Quadrupedal Arboreal Locomotion In The Siberian Chipmunk (Tamias Sibiricus), Andrew R. Lammers, Ulrich Zurcher
Torque Around The Center Of Mass: Dynamic Stability During Quadrupedal Arboreal Locomotion In The Siberian Chipmunk (Tamias Sibiricus), Andrew R. Lammers, Ulrich Zurcher
Physics Faculty Publications
When animals travel on tree branches, avoiding falls is of paramount importance. Animals swiftly running on a narrow branch must rely on movement to create stability rather than on static methods. We examined how Siberian chipmunks (Tamias sibiricus) remain stable while running on a narrow tree branch trackway. We examined the pitch, yaw, and rolling torques around the center of mass, and hypothesized that within a stride, any angular impulse (torque during step time) acting on the center of mass would be canceled out by an equal and opposite angular impulse. Three chipmunks were videotaped while running on a 2 …
Formulation Of The Dutch Atmospheric Large-Eddy Simulation (Dales) And Overview Of Its Applications, Thijs Heus, C. C. Van Heerwaarden, Harmen J.J. Jonker, A. Pier Siebesma, S. Axelsen, K. Van Den Dries, O. Geoffroy, A. F. Moene, D. Pino, S. R. De Roode, J. Vilà-Guerau De Arellano
Formulation Of The Dutch Atmospheric Large-Eddy Simulation (Dales) And Overview Of Its Applications, Thijs Heus, C. C. Van Heerwaarden, Harmen J.J. Jonker, A. Pier Siebesma, S. Axelsen, K. Van Den Dries, O. Geoffroy, A. F. Moene, D. Pino, S. R. De Roode, J. Vilà-Guerau De Arellano
Physics Faculty Publications
The current version of the Dutch Atmospheric Large-Eddy Simulation (DALES) is presented. DALES is a large-eddy simulation code designed for studies of the physics of the atmospheric boundary layer, including convective and stable boundary layers as well as cloudy boundary layers. In addition, DALES can be used for studies of more specific cases, such as flow over sloping or heterogeneous terrain, and dispersion of inert and chemically active species. This paper contains an extensive description of the physical and numerical formulation of the code, and gives an overview of its applications and accomplishments in recent years.