The widely used Betz invariants can be categorized as invariants of vorticity moments or impulses in plane motion for mostly inviscid vortex  ow. These invariants have served as a foundation of vortex roll-up process analysis as well as benchmarks to estimate numerical simulation errors for vortex  ow. The analysis starts from a more general integral divergence relation in rationalmechanics t...

This work presents an approach to the analysis of duct-augmented wind turbines using Computational Fluid Dynamics (CFD). The main objective is find optimum duct shape and design that gives maximum boost performance turbines. A surrounding rotor able increase power coefficient above Betz limit, so it has attracted great attention for many years. In this work, extensive augmented presented, consi...

This paper presents the aerodynamic design of low noise wind turbine blades using Betz and Joukowski concepts. The aerodynamic model is based on Blade Element Momentum theory whereas the aeroacoustic prediction model is based on the BPM model. The investigation is started with a 3MW baseline/reference turbine rotor with a diameter of 80 m. To reduce the noise emission from the baseline rotor, t...

Installing a turbine in duct generally increases the flow through rotor. If there is confinement due to limited water depth, presence of lateral boundaries, or adjacent turbines, further enhancement rotor will be achieved. Extensive studies ducted turbines uni-directional have shown that rotor-based power coefficientCpcan exceed Betz-Joukowsky limit (BJL) for bare turbine, whereas exceedance BJ...

Normal chick embryos swallow and utilize the albumen in the egg between the 11th and 15th day of incubation (Witschi, 1949). They use approximately two-thirds of the yolk by the end of incubation (Romanoff & Romanoff, 1949). Thus the embryo has access to 4 g of protein in the albumen and 3 g of protein in the yolk (Romanoff & Romanoff, 1949). Embryos which have been hypophysectomized by partial...

10 Streamlining Development of a Multimillion-Line Computational Chemistry Code robin M. Betz and ross C. walker Software engineering methodologies can be helpful in computational science and engineering projects. Here, a continuous integration software engineering strategy is applied to a multimillion-line molecular dynamics code; the implementation both streamlines the development and release...

This paper proposes and simulates vertical airborne wind energy (AWE) farms based on multi-aircraft systems with high power density (PD) per ground area. These consist of many independently located that are flying at the same inclination angle, but different tether lengths, such all aircraft fly in a large planar elliptical area is to tethers. The individual assigned non-overlapping flight cyli...

We give lower and upper bounds for the first eigenvalue of geodesic balls in spherically symmetric manifolds. These lower and upper bounds are C0-dependent on the metric coefficients. It gives better lower bounds for the first eigenvalue of spherical caps than those from Betz-Camera-Gzyl. Mathematics Subject Classification: (2000):35P15, 58C40.