In the present paper effect of angle of attack on stability derivatives in pitch of delta wing for the attached shock case is been studied. A strip theory is used in which strips at different span-wise locations are independent. This combines with the similitude to give a piston theory. In the present theory, the similitude, and the piston theory have been extended to a flat wing with straight ...

Pumped hydro energy storage (PHES) is currently the only proven large-scale energy storage technology. Frequent changes between pump and turbine operations pose significant challenges in the design of a pump-turbine runner with high efficiency and stability, especially for ultrahigh-head reversible pump-turbine runners. In the present paper, a multiobjective optimization design system is used t...

As wind turbines continue to grow larger, problems associated with adverse aerodynamic loads will grow more critical. Thus, the wind energy technical community has begun to seriously consider the potential of aerodynamic control methodologies for mitigating adverse aerodynamic loading. Spatial and temporal attributes of the structures and processes present in these flow fields hold important im...

The aim of this paper is to investigate the performance of a specially designed micro wind turbine for urban environment where the wind speed is usually low. Differing from the traditional wind turbine that can be connected directly to the grid, the micro wind turbine is linked to a small generator and mainly used for local applications. The advantage of the micro wind turbine is that, apart fr...

In the title compound, C(12)H(9)Br(2)N, the dihedral angle between the benzene rings is 47.32 (5)°, whereas the pitch angles, or the angles between the mean plane of each aryl group 'propeller blade' and the plane defined by the aryl bridging C-N-C angle, are 18.1 (2) and 31.7 (2)°. No inter-molecular N-H hydrogen bonding is present in the crystal; however, there is a short inter-molecular Br⋯B...

The inclination of the scapular blade and the resting pose of the forelimb in dinosaurs differ among reconstructions and among skeletal mounts. For most dinosaurian taxa, no attempt has previously been made to quantify the correct resting positions of these elements. Here, we used data from skeletons preserved in articulation to quantify the resting orientations of the scapula and forelimb in d...

The important step in the turbine aerodynamic design is generation of blade element profiles to achieve the required flow deflection and smooth flow acceleration with minimum losses. During profile generation, in addition to aerodynamic performance, additional constraints of thermal, structural and castability requirements need to be considered. Thus profile generation is a trade-off between co...

In this study, the stability of conservative spring-mass running using a fixed angle of attack is addressed. For a given initial condition, different angles of attack result in periodic movement patterns. We apply a simple stride-to-stride analysis to prove the stability. Spring-like leg operation together with angle of attack control enables selfstabilised running.