Abstract. It is found in collisionless Electron Temperature Gradient (ETG) turbulence simulations that, while zonal flows are weak at early times, the zonal flows continue to grow algebraically (proportional to time). These fine-scale zonal flows have a radial wave number such that krρi > 1 and krρe < 1. Eventually, the zonal flows grow to a level that suppresses the turbulence due to ExB shear...

As interest in marine renewable energy increases, observations are crucial for understanding the environments that prospective turbines will encounter. Data from an acoustic Doppler velocimeter in Puget Sound, WA are used to perform a detailed characterization of the turbulent flow encountered by a turbine in a tidal strait. Metrics such as turbulence intensity, structure functions, probability...

In this paper we analyze multiple-input multiple-output (MIMO) free-space optical (FSO) communication systems with Q-ary pulse position modulation (PPM) and avalanche photodiodes (APDs) in the receiver array in the presence of atmospheric turbulence, and derive the general maximum-likelihood (ML) detection rule and the Chernoff bound on error probability (Pe) for the MIMO setup. The obtained an...

Landscapes respond to climate, tectonic motions and sea level, but this response is mediated by sediment transport. Understanding transmission of environmental signals is crucial for predicting landscape response to climate change, and interpreting paleo-climate and tectonics from stratigraphy. Here we propose that sediment transport can act as a nonlinear filter that completely destroys (“shre...

This paper describes numerical implementation of a newly developed hybrid model, T-bbb/7'-TAB, into an existing computational fluid dynamics (CFD) program for primary and secondary breakup simulation of liquid jet atomization. This model extend two widely used models, the Kelvin-Helmholtz (KH) instability of Reitz (blob model) and the Taylor-Analogy-Breakup (TAB) secondary droplet breakup by O'...

In this paper we investigate the action of ambient turbulence on thermohaline interleaving using both theory and numerical calculations in combination with observations from Meddy Sharon and the Faroe Front. We improve upon the highly simplified models of ambient turbulence used previously by allowing turbulent diffusivities of momentum, heat and salt to depend on background gradients and to ev...

Wc examine and intcrcompare the LF plasma wave turtmlcnce at three comets: Grigg-Skjellertrp (GS), Giacobini Zinncr (GZ), and Ilallcy (11). All three have power spectral peaks at the local ion cyclotron frequency (the pump wave) at -10 -2 IIz, and a power-law fall-off at higher frequencies that suggest the development of turbulent cascades [Acrm4 1986]. The power laws for the three comets are a...

In this paper the authors investigate the action of ambient turbulence on thermohaline interleaving using both theory and numerical calculations in combination with observations from Meddy Sharon and the Faroe Front. The highly simplified models of ambient turbulence used previously are improved upon by allowing turbulent diffusivities of momentum, heat, and salt to depend on background gradien...

A new framework for spatio-temporally adaptive turbulence simulations is proposed. The method is based on a variable-fidelity representation that tightly integrates numerics and modelling of subgrid-scale turbulence and aims to capture the flow physics on a near-optimal adaptive mesh. The integration is achieved by combining hierarchical wavelet-based computational modelling with spatially and ...

A dynamical approach, rather than the usual statistical approach, is taken to explore the physical mechanisms underlying the nonlinear transfer of energy, the damping of the turbulent fluctuations, and the development of coherent structures in kinetic plasma turbulence. It is argued that the linear and nonlinear dynamics of Alfvén waves are responsible, at a very fundamental level, for some of ...