62 research outputs found
Vortical and Wave Modes in 3D Rotating Stratified Flows: Random Large Scale Forcing
Utilizing an eigenfunction decomposition, we study the growth and spectra of
energy in the vortical and wave modes of a 3D rotating stratified fluid as a
function of . Working in regimes characterized by moderate
Burger numbers, i.e. or , our results
indicate profound change in the character of vortical and wave mode
interactions with respect to . As with the reference state of
, for the wave mode energy saturates quite quickly
and the ensuing forward cascade continues to act as an efficient means of
dissipating ageostrophic energy. Further, these saturated spectra steepen as
decreases: we see a shift from to scaling for
(where and are the forcing and dissipation scales,
respectively). On the other hand, when the wave mode energy
never saturates and comes to dominate the total energy in the system. In fact,
in a sense the wave modes behave in an asymmetric manner about .
With regard to the vortical modes, for , the signatures of 3D
quasigeostrophy are clearly evident. Specifically, we see a scaling
for and, in accord with an inverse transfer of energy, the
vortical mode energy never saturates but rather increases for all . In
contrast, for and increasing, the vortical modes contain a
progressively smaller fraction of the total energy indicating that the 3D
quasigeostrophic subsystem plays an energetically smaller role in the overall
dynamics.Comment: 18 pages, 6 figs. (abbreviated abstract
Non-Gaussian Distributions in Extended Dynamical Systems
We propose a novel mechanism for the origin of non-Gaussian tails in the
probability distribution functions (PDFs) of local variables in nonlinear,
diffusive, dynamical systems including passive scalars advected by chaotic
velocity fields. Intermittent fluctuations on appropriate time scales in the
amplitude of the (chaotic) noise can lead to exponential tails. We provide
numerical evidence for such behavior in deterministic, discrete-time passive
scalar models. Different possibilities for PDFs are also outlined.Comment: 12 pages and 6 figs obtainable from the authors, LaTex file,
OSU-preprint-
Planning charging infrastructure deployment: A new spatio-temporal model. Extended abstract for the Euro Working Group on Transportation 2021
Extended abstract for the Euro Working Group on Transportation 2021The environmental objectives set by the various international summits call for greening the transportation sector, which is responsible for a significant share of greenhouse gas emissions. The current trend is a transition from the current fleet of vehicles to a fleet of electric vehicles. To allow this transition, it is necessary to ensure the acceptance of the electric vehicle among its users. This acceptance requires the deployment of a charging infrastructure adapted to user needs. In this study, we propose a multi-criteria charging infrastructure deployment model, not only geographically but also temporally, in order to accompany this transition. The model is oriented to meet the needs of users, assuming that charging demand will follow if a suitable infrastructure is proposed. We then conduct a comparison study between the new model and the classic deployment models found in the literature
Too much or not enough? Planning electric vehicle charging infrastructure: A review of modeling options
International audienc
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