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After specifying the general context and needs of the paragliding industry, a new model to compute paraglider cloth dynamics is presented. Applications in research and development are then shown. Results are very promising: using simulations is drastically changing the way paragliders are being developed. Then the firsts steps towards the use of immersed boundaries with Lattice Boltzmann method for the highly coupled, transient high fidelity fluid–structure interaction simulation of paragliders are presented. Despite strong bias due to under-resolved boundary layers, numerical results of the cloth deformations are in an acceptable agreement with wind tunnel measurements conducted in a previous study on a small and simple parachute geometry.

Effects of infection time by Fusarium graminearumon ear blight, deoxynivalenol and zearalenone production in wheatAlthough it is generally agreed that most Fusariumhead blight infection takes place during the wheat flowering period, very rainy conditions at the end of the plant growth, such as occurred in France in 2007, raise the question of the possibility of late infections on the development of the disease and the production of toxins. Such infections are not taken into account by predictive models. To explore the effect of infection time on disease severity, Fusarium-damaged kernels (FDK), desoxynivalenol (DON) and zearalenone (ZON), an experiment was set up in 2009 on two varieties. The experiment had a split-plot design. Plots were inoculated by spraying Fusarium graminearum conidiaat different stage, from heading to ripening. Inoculation time had a significant effect on disease severity, FDK, DON and ZON levels (P<0.0001), as well as interaction between variety and inoculation time. The results of this trial have shown no significant difference between infection at heading, anthesis and post-anthesis until 15 days for disease severity, FDK and mycotoxins levels. Nevertheless, this trial has suggested different behaviour between the two varieties according to infection time and toxin accumulation. The period of high susceptibility to Fusarium graminearumhas appeared unstable between varieties, ranging from closed to flowering to a large period from heading to several days after flowering.

Density profile information is invaluable to plasma experiments. In particular, the edge and mantle plasma density profile is believed to influence core plasma behaviour of fusion devices such as tokamaks. In low density plasmas, light emission caused by neutral hydrogen gas injection and subsequent excitation can be used to measure the local plasma parameters. A neutral penetration model is required to evaluate plasma density from H?light emission. This paper verifies that a simple collisionless three-dimensional neutral penetration model can be utilized in low-density, low-temperature plasmas. Since the H?emission intensity can be linked directly to the local electron density, this model permits the reconstruction of the density profile well beyond the last closed flux surface of the plasma.

New results on the phase diagram of KNbO 3 determined, from 10 to 650 K up to 30 GPa, with Raman scattering are given. On increasing pressure the Curie temperature T c was found to shift down regularly from 700 K, at atmospheric pressure, to 20 K at ∼25 GPa. Up to 20 GPa, the pressure dependence of T c follows a classical regime described by the Ising model where the dipolar interaction follow a i 2 /v law, where i is the off-center displacement and v the unit cell volume. This behaviour found also for the ice VII-VIII is very likely encountered in a number of (anti)ferroelectric-paraelectric transformations involving positional disorder.

The Electric Tokamak, a low field ITER sized device with R = 5 m, has been operating with well equilibrated clean plasmas since January 2000. Short, 0.9 s, discharges with a central energy confinement time τ_E(0) = 150 ms are now routinely obtained at a toroidal field B = 0.1 T with kT_e, kT_i&simeq;120 eV. The discharges are feedback controlled in up/down position and in plasma current. Biased electrode driven H modes have been obtained that compare well with the results obtained on CCT by R.J. Taylor and align with the `neoclassical bifurcation' theory of K.C. Shaing. Very successful second harmonic ion heating has been demonstrated with the ICRF antenna outside the vacuum system and with 50% single pass absorption. ICRF heated discharges indicate that poloidal rotation sufficient for edge bifurcation (H mode) may soon be achieved by ICRF induced fast ion losses. The threshold electrode biasing current required for bifurcated poloidal rotation has so far been reduced by 70% owing to ICRH driven ion orbit loss. The remaining critical ICRF item needed for the exploration of high beta plasma equilibria is the demonstration of the required current profile shaping. It is expected that mode conversion in the ion-ion hybrid regime, with high field side launch, will allow the current drive required to approach and exceed the Troyon beta limit. In 1-D full wave calculations, high harmonic current drive appears most promising at higher beta. Achieving the goal of plasma equilibration near unity beta will require 10 s long discharges (at kT = 3 keV, n_e = 3×10¹⁹ m^-3, B = 0.25 T) because of current profile shaping requirements.

This article presents the large-eddy simulation (LES) of a low-pressure turbine (LPT) nozzle guide vane (NGV) for different Reynolds (Re) and Mach (Ma) numbers with or without inlet turbulence prescribed. The analysis is based on a slice of an LPT blading representative of a midspan flow, where secondary flows, hub, and shroud effects are lower. The characteristic Re of the LPT can vary by a factor of four between take-off and cruise conditions. In addition, the LPT operates at different Ma values, and the incident flow can have significant levels of turbulence due to upstream blade wakes. This article investigates numerically using LES the flow around an LPT blading with three different Reynolds number Re = 175,000 (cruise), 280,000 (mid-level altitude), and 500,000 (take-off) keeping the same characteristic Mach number Ma = 0.2 and three different Mach number Ma = 0.2, 0.5, and 0.8 keeping the same Reynolds number Re = 280,000. These different simulations are performed with 0% freestream turbulence (FST) followed by inlet turbulence (6% FST). The study focuses on the influence of these three parameters (Re, Ma, and upstream turbulence) on different flow characteristics: pressure distribution around the blade, near-wall flow behavior, loss generation, and turbulent kinetic energy (TKE) budget. The results show an earlier boundary layer separation on the aft region of the blade suction side when the Re is increased, while the increase of the Ma delays separation, similar to freestream turbulence. The TKE budget led on the different cases shows the predominant effect of the turbulent production and diffusion in the wake, the axial evolution of these different terms being relatively insensitive to Re and Ma.

Energy dispersive X-ray diffraction was used at room temperature to investigate the phase diagram of the KNbO3perovskite up to 19GPa. The results confirm the location of the ferroelectric–paraelectric transition at ∽9GPa and support the transformation of the orthorhombic solid to the tetragonal solid in the 4–5GPa pressure range. The variation of the cell volume was fitted to a Murnaghan equation of state whose parameters are discussed.

In gas turbine, multi-stage row blading and technological effects can exhibit significant differences for the flow compared with isolated smooth blade rows. Upstream stages promote a non-uniform flow field at the inlet of the downstream rows that may have large effects on mixing or boundary layer transition processes. The rows of current turbines (and compressors) are already very closely spaced. Axial gaps between adjacent rows of approximately 1/4 to 1/2 of the axial blade chord are common practice. Future designs with higher loading and lower aspect ratios, i.e., fewer and bigger blades, and the ever present aim at minimizing engine length or compactness, will aggravate this condition even further. Interaction between cascade rows will therefore keep increasing and need to be taken into account in loss generation estimation. Also the cavities at hub platform induce purge flow blowing into main annulus and additional losses for the turbine. A robust method to account for the loss generated due to these different phenomena needs to be used. The notion of exergy (energy in the purpose to generate work) provides a general framework to deal with the different transfers of energy between the flow and the gas turbine. This study investigates the flow in a two-stage configuration representative of a low-pressure turbine including hub cavities based on large eddy simulation (LES). A description of the flow in the cavities, the main annulus, and at rim seal interface is proposed. The assessment of loss generated in the configuration is proposed based on an exergy analysis. The study of losses restricted to boundary layer contributions and secondary flows show the interaction processes of secondary vortices and wake generated in upstream rows on the flow in downstream rows.

1.5 μm GaInAs multiquantum well distributed feedback lasers have been successfully fabricated on InP grating substrate by GSMBE. DFB mode oscillation at high output power (50 mW) and narrow linewidth (1.3 MHz) have been obtained.

Purge air is injected in cavities at the hub of axial turbines to prevent hot mainstream gas ingestion into interstage gaps. This process induces additional losses for the turbine due to an interaction between the purge and mainstream flow. This paper investigates the flow in a low-speed linear cascade rig with upstream hub cavity at a Reynolds number commonly observed in modern low-pressure turbine stages by the use of numerical simulation. Numerical predictions are validated by comparing against experimental data available. Three different purge mass flow rates are tested using three different rim seal geometries. Numerical simulations are performed using a large-eddy simulation (LES) solver on structured grids. An investigation of the different mechanisms associated with the turbine flow including cavity and purge air is intended through this simplified configuration. The underlying mechanisms of loss are tracked using an entropy formulation. Once described for a baseline case, the influence of purge flow and rim seal geometry on flow mechanisms and loss generation is described with the emphasis to obtain design parameters for losses reduction. The study quantifies loss generation due to the boundary layer on wetted surfaces and secondary vortices developing in the passage. The analysis shows different paths by which the purge flow and rim seal geometry can change loss generation including a modification of the shear layer between purge and mainstream, interaction with secondary vortices, and a modification of the flow behavior close to hub compared with a smooth configuration. The study shows the influence of purge flow rate and swirl on the strengthening of secondary vortices in the passage and the ability of axial overlapping rim seal to delay the development of secondary vortices compared with simple axial gaps.

Ultra-high bypass ratio (UHBR) engines are designed as compact as possible and are characterized by a short asymmetric air inlet and heterogeneous outlet guide vanes (OGVs). The flow close to the fan is therefore circumferentially nonuniform (or distorted) and the resulting noise might be impacted. This is studied here at take-off conditions by means of a simulation of the unsteady Reynolds-averaged Navier–Stokes (URANS) equations of a full-annulus fan stage. The model includes an asymmetric air inlet, a fan, heterogeneous OGVs, and homogeneous inlet guide vanes (IGVs). Direct acoustic predictions are given for both inlet and aft noises. A novel hydrodynamic/acoustic splitting method based on a modal decomposition is developed and is applied for the aft noise analysis. The noise mechanisms that are generally considered (i.e., interaction of fan-blade wakes with OGVs and fan self-noise) are shown to be impacted by the distortion. In addition, new sources caused by the interaction between the stationary distortion and the fan blades appear and contribute to the inlet noise.

A safe, convenient and easily reproducible synthesis of the photoaffinity label (V) starting from commercially available nucleoside (I) is given.