Flowing low temperature atmospheric pressure plasma devices have been used in many technological applications ranging from energy efficient combustion through to wound healing and cancer therapy. The generation of the plasma causes a sudden onset of turbulence in the inhomogeneous axisymmetric jet flow downstream of the plasma plume. The mean turbulent velocity fields are shown to be self-simil...

A subcritical transition to turbulence in magnetized Keplerian shear flows is investigated by using a statistical approach. Three-dimensional numerical simulations of the shearing box equations with zero net magnetic flux are employed to determine the transition from decaying to sustained turbulence as a function of the magnetic Reynolds number R{m}. The results reveal no clear transition to su...

Shear layer separated from a bluff bodyshaped structure is very sensitive to the inflow turbulence. Appropriate numerical simulation of the atmospheric boundary layer plays key points in the numerical study of the aerodynamic forces experienced by the structures immersed in the ABL. This paper describes the methods to simulate the inflow turbulence corresponding to different surface roughness. ...

Wind turbines require methods to predict the power produced as inflow conditions change. We compare the standard method of binning with a turbulence renormalization method and a machine learning approach using a data set derived from simulations. The method of binning is unable to cope with changes in turbulence; the turbulence renormalization method cannot account for changes in shear other th...

The modi cation of turbulence in the edge plasma of the DIII{D tokamak at the transition from the low to the high mode of con nement is investigated with a phase-contrast imaging diagnostic. The amplitude and radial correlation length of the turbulence in the con nement region decrease at the transition, whereas the decorrelation time increases. The transition model of Biglari, Diamond, and Ter...

Recent numerical studies suggest that in pipe and related shear flows, the region of phase space separating laminar from turbulent motion is organized by a chaotic attractor, called an edge state, which mediates the transition process. We here confirm the existence of the edge state in laboratory experiments. We observe that it governs the dynamics during the decay of turbulence underlining its...

◮ We study Scrape-Off Layer (SOL) turbulence through simulations that evolve the plasma dynamics as the interplay of plasma source from the core, perpendicular transport, and losses at the limiter plates ◮ We identify the SOL turbulence regimes, defining the regions of existence of the Ballooning Modes [resistive (RBM) and inertial (IBM)] and the Drift Waves [resistive (RDW) and inertial (IDW)]...

An energy conserving model of MHD turbulence is described that predicts both mode coupling and turbulent dissipation. The dissipation takes the form of anomalous resistivity and viscosity due to turbulent magnetic fields. The model predicts a dualcascade of energy to large wave numbers and magnetic flux to small wave numbers. Turbulent rearrangement of equilibrium magnetic shear gene rates reso...

Aims. Guided by the duality of turbulence (random versus coherent motions), we seek coherent structures in the turbulent velocity field of molecular clouds, anticipating their importance in cloud evolution. Methods. We analyse a large map (40’ by 20’) obtained with the HERA multibeam receiver (IRAM-30m telescope) in a high latitude cloud of the Polaris Flare at an unprecedented spatial (11) and...

Results from recent experiment and numerical simulation point towards a picture of the L-H transition in which edge shear flows interacting with edge turbulence create the conditions needed to produce a non-zero turbulent Reynolds stress at and just inside the LCFS during L-mode discharges. This stress acts to reinforce the shear flow at this location and the flow drive gets stronger as heating...