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The simulation of the complex flow in a wind turbine wake is a challenging problem. To date, much of the research has been inhibited by both the time and computational costs associated with turbulence modelling. Additionally, the majority of numerical investigations focus on turbine performance and therefore neglect the near wake of a Horizontal Axis Wind Turbine (HAWT) entirely. This investigation focuses on experimentally and numerically quantifying the near wake structure of a model HAWT. The Shear Stress Transport (SST) k − ω , Elliptical-Blending Reynolds Stress Model (EB-RSM) and the Reynolds Stress Transport (RST) turbulence models were used to model a turbine wake in the current study, with the results verified against experimental hot-wire data. Near wake velocity and turbulence characteristics were investigated to determine if low-order models can accurately predict the magnitude and distribution of velocity and turbulence values in the near wake of a model HAWT. The HAWT model was operated at two TSR values of 2.54 and 3.87. All models predicted velocity deficit values to within 2–4% and 4–7% of experimental results for TSR values of 2.54 and 3.87 respectively. Results showed that all models were able to accurately predict the mean velocity deficit generated in the near wake. All models were able to predict the fluctuating u and v velocity components in the near wake to the correct order of magnitude with the fluctuating velocity components having an inverse Laplace distribution in the wake. However, all models under-estimated the magnitude of these velocity values with predictions as low as −43% of experimental results.

A review of wind turbine aerodynamics research is presented. The review is limited to Horizontal Axis Wind Turbine (HAWT) investigations. The focus is on recent near wake experiments, wake predictions by commercial CFD codes and current FSI and structural modelling attempts. For the near wake, the review considers experiments carried out in controlled conditions whereby the incoming freestream is perpendicular to the rotor plane. Additional anomalies such as wind shear, gusts and yaw transition are not considered. The survey of 3D commercial codes is also focused on HAWT models in parallel flow conditions. Finally, the structural models reviewed are divided into two separate categories: 1) blade deflection and performance under aerodynamic loads, and 2) the vibrational response of blades under aerodynamic loading. The aim is to highlight common trends within near wake experiments and investigate both CFD and FE modelling strategies – to identify current limitations and future opportunities within the sector.

l-lysine (Lys) is an essential amino acid that is added to foods and dietary supplements. Lys may interact with mineral nutrients and affect their metabolism. This study examined the effect of dietary Lys supplementation on the bioavailability of copper (Cu) and iron (Fe). Weanling male Sprague-Dawley rats were fed one of five diets (20% casein) for 4 weeks containing normal Cu and Fe (control) or low Cu or Fe without (LCu, LFe) or with (LCu+Lys, LFe+Lys) addition of 1.5% Lys. Final body weights, body weight gains and food consumption of the rats did not differ (P≥0.05) among diet groups. Rats fed the low Cu or Fe diets showed changes in nutritional biomarkers compared to control rats, demonstrating reduced Cu and Fe status, respectively. Hematological parameters, serum ceruloplasmin activity and Cu and Fe concentrations in serum, liver, kidney and intestinal mucosa were unaffected (P≥0.05) by Lys supplementation. These results indicate that in the context of an adequate protein diet, Lys supplementation at a relatively high level does not affect Cu or Fe bioavailability in rats.

In this study, the near-field (up to three chord lengths) development of a wing-tip vortex is numerically investigated at two angles of attack (five and ten degrees). The application of a vorticity confinement model to an Unsteady Reynolds averaged Navier–Stokes (URANS) model and Large Eddy Simulation (LES) is examined with the focus of preventing the rapid dissipation of vorticity in a wing-tip vortex. Vortex core size and trajectory were predicted well by the LES model, whereas the URANS model predicted a large vortex core, which remained constant with downstream distance. The LES model correctly predicted the jet-like axial velocity for an angle of attack of ten degrees and the LES and experimental axial velocity excess had the same value of 111% of free-stream velocity at two chord lengths downstream. The LES model predicted the turbulence in the vortex reasonably well as the maximum turbulent root mean square (rms) velocities were within 15% and 35% of experimental values at two and three chord lengths downstream for angles of attack of ten and five degrees respectively. The URANS model predicted the mean flow for an angle of attack of five degrees reasonably well but greatly under-predicted the mean flow for an angle of attack of ten degrees and the turbulence levels at all downstream locations.

Sodium (Na) and potassium (K) are essential nutrients. Like people in many Western societies, Canadians consume too much Na and not enough K, both of which contribute to hypertension. We analysed the Na and K content of 154 food composites, broadly representative of the foods most commonly consumed in Canada, from the Canadian Total Diet Study collection of 2007. Foods were prepared as if for home consumption before compositing. No salt was added during food preparation. Samples prepared by aqueous extraction were analysed by atomic emission (Na) or atomic absorption spectrometry (K). Processed foods and soups contained large amounts of Na per reference amount (serving) of the food, with 17 samples containing over 1/3 of the Adequate Intake (AI) for adults, or >500 mg Na/serving. Fluid milk, unprocessed meats and several fruits and vegetables contained large amounts of K per reference amount, with 11 samples containing over 10% of the AI for adults, or >470 mg K/serving. Na:K molar ratios were typically either high or low, with few values near unity. Thus, with few exceptions, foods high in Na were lower in K, and vice versa. Through judicious food selection it may be possible for consumers to decrease Na intake while increasing K, with associated health benefits. Such choices would be consistent with common nutrition advice to decrease consumption of processed foods, while increasing intakes of fresh fruits and vegetables.

To assess the comparative effectiveness of relaxation instructions and frontalis electromyographic (EMG) biofeedback in the treatment of muscle-contraction (tension) headaches, 21 volunteers were assigned to either a relaxation training group, a biofeedback group or a no-treatment control group. Each group met for six 1/2-hr sessions. The EMG biofeedback and the relaxation instructions resulted in significant decreases in reported headache activity. Both procedures were significantly more effective than the control procedure, but did not differ significantly from each other in effectiveness. The effectiveness of the two experimental procedures was maintained at follow-up. Frontalis EMG levels were higher during sessions in which a headache was reported than in sessions when no headache was reported. The importance of individual differences is emphasized.