Design Drivers of Energy-Efficient Transport Aircraft

The fuel energy consumption of subsonic air transportation is examined. The focus is on identification and quantification of fundamental engineering design tradeoffs which drive the design of subsonic tube and wing transport aircraft. The sensitivities of energy efficiency to recent and forecast technology developments are also examined

The phenomenon of unemployment among young people - the NEET problem

This paper presents an analysis of the size and characteristics of the NEET population in Poland compared to other EU-27 Member States. NEET is an acronym for Not in Employment, Education or Training. Thus, the aim of this article is to analyse the phenomenon of unemployment of the youth in the EU and in Poland with a particular emphasis put on the problem of NEETs, which seems to be one of the most significant socio-economic issues of the present decade concerning the labour market of the youth

Aerodynamics of heat exchangers for high-altitude aircraft

Reduction of convective beat transfer with altitude dictates unusually large beat exchangers for piston- engined high-altitude aircraft The relatively large aircraft drag fraction associated with cooling at high altitudes makes the efficient design of the entire heat exchanger installation an essential part of the aircraft's aerodynamic design. The parameters that directly influence cooling drag are developed in the context of high-altitude flight Candidate wing airfoils that incorporate heat exchangers are examined. Such integrated wing-airfoil/heat-exchanger installations appear to be attractive alternatives to isolated heat.exchanger installations. Examples are drawn from integrated installations on existing or planned high-altitude aircraft

Development and testing of airfoils for high-altitude aircraft

Specific tasks included airfoil design; study of airfoil constraints on pullout maneuver; selection of tail airfoils; examination of wing twist; test section instrumentation and layout; and integrated airfoil/heat-exchanger tests. In the course of designing the airfoil, specifically for the APEX test vehicle, extensive studies were made over the Mach and Reynolds number ranges of interest. It is intended to be representative of airfoils required for lightweight aircraft operating at extreme altitudes, which is the primary research objective of the APEX program. Also considered were thickness, pitching moment, and off-design behavior. The maximum ceiling parameter M(exp 2)C(sub L) value achievable by the Apex-16 airfoil was found to be a strong constraint on the pullout maneuver. The NACA 1410 and 2410 airfoils (inverted) were identified as good candidates for the tail, with predictable behavior at low Reynolds numbers and good tolerance to flap deflections. With regards to wing twist, it was decided that a simple flat wing was a reasonable compromise. The test section instrumentation consisted of surface pressure taps, wake rakes, surface-mounted microphones, and skin-friction gauges. Also, a modest wind tunnel test was performed for an integrated airfoil/heat-exchanger configuration, which is currently on Aurora's 'Theseus' aircraft. Although not directly related to the APEX tests, the aerodynamics or heat exchangers has been identified as a crucial aspect of designing high-altitude aircraft and hence is relevant to the ERAST program

Modeling of heavy-gas effects on airfoil flows

Thermodynamic models were constructed for a calorically imperfect gas and for a non-ideal gas. These were incorporated into a quasi one dimensional flow solver to develop an understanding of the differences in flow behavior between the new models and the perfect gas model. The models were also incorporated into a two dimensional flow solver to investigate their effects on transonic airfoil flows. Specifically, the calculations simulated airfoil testing in a proposed high Reynolds number heavy gas test facility. The results indicate that the non-idealities caused significant differences in the flow field, but that matching of an appropriate non-dimensional parameter led to flows similar to those in air

A general numerical unsteady nonlinear lifting line model for engineering aerodynamics studies

The lifting line theory is widely used for obtaining aerodynamic performance results in various engineering fields, from aircraft conceptual design to wind power generation. Many different models were proposed, each tailored for a specific purpose, thus having a rather narrow applicability range. This paper presents a general lifting line model capable of accurately analysing a wide range of engineering problems involving lifting surfaces, both steady-state and unsteady cases. It can be used for lifting surface with sweep, dihedral, twisting and winglets and includes features such as nonlinear viscous corrections, unsteady and quasi-steady force calculation, stable wake relaxation through fictitious time marching and wake stretching and dissipation. Possible applications include wing design for low speed aircraft and unmanned aerial vehicles, the study of high-frequency avian flapping flight or wind turbine blade design and analysis. Several validation studies are performed, both steady-state and unsteady, the method showing good agreement with experimental data or numerical results obtained with more computationally-expensive methods. Keywords: lifting line model, unsteady lifting line, 2D-3D coupling, lifting surface aerodynamics, flapping wing, horizontal-axis wind turbin

Fluctuating Elastic Rings: Statics and Dynamics

We study the effects of thermal fluctuations on elastic rings. Analytical expressions are derived for correlation functions of Euler angles, mean square distance between points on the ring contour, radius of gyration, and probability distribution of writhe fluctuations. Since fluctuation amplitudes diverge in the limit of vanishing twist rigidity, twist elasticity is essential for the description of fluctuating rings. We find a crossover from a small scale regime in which the filament behaves as a straight rod, to a large scale regime in which spontaneous curvature is important and twist rigidity affects the spatial configurations of the ring. The fluctuation-dissipation relation between correlation functions of Euler angles and response functions, is used to study the deformation of the ring by external forces. The effects of inertia and dissipation on the relaxation of temporal correlations of writhe fluctuations, are analyzed using Langevin dynamics.Comment: 43 pages, 9 Figure

Comparison of Fixed and Variable Pitch Actuators for Agile Quadrotors

This paper presents the design, analysis and experimental testing of a variable- pitch quadrotor. A custom in-lab built quadrotor with on-board attitude stabi- lization is developed and tested. An analysis of the dynamic di erences in thrust output between a xed-pitch and variable-pitch propeller is given and validated with simulation and experimental results. It is shown that variable-pitch actuation has signi cant advantages over the conventional xed-pitch con guration, includ- ing increased thrust rate of change, decreased control saturation, and the ability to quickly and e ciently reverse thrust. These advantages result in improved quadro-tor tracking of linear and angular acceleration command inputs in both simulation and hardware testing. The bene ts should enable more aggressive and aerobatic ying with the variable-pitch quadrotor than with standard xed-pitch actuation, while retaining much of the mechanical simplicity and robustness of the xed-pitch quadrotor.Aurora Flight Sciences Corp.National Science Foundation (U.S.) (Graduate Research Fellowship Grant 0645960

Wpływ funduszy Unii Europejskiej na rynek pracy osób młodych na przykładzie województwa zachodniopomorskiego w perspektywie finansowej 2014-2020

The young people are part of the disadvantaged groups on the labour market, so support for these groups on the labour market grows from the tradition of fighting for equality and civiliza¬tion development. The aim of the discussion is therefore to present a the situation of young people on the labour market, ze with particular emphasis on the West Pomeranian labour market and attempt to preliminary verification of EU funds for the 2014-2020 period on the labour market of young people in the voivodeship. At the outset, it contains discussion of in the labour market for young people on the example of the West Pomerania province. To better illustrate, it was used activity rate, employment rate and unemployment rate. The subject of the next part of the was European Union funds addressed to young people with particular emphasis on the Operational Progranune Knowl¬edge Education Development 2014-2020 for West Pomerania voivodship. Therefore it was decided to present the existing sub-measures of these programs. End portion are the major conclusions from the discussion

The diversity of angiogenesis in diabetic vascular complications

Diabetes is one of the major healthcare problems and it is considered a global epidemic of the 21st century. Long lasting hyperglycaemia contributes to the development of vascular diabetic complications such as retinopathy, nephropathy or diabetic foot syndrome (DFS). The pathogenesis of each diabetic complication is multifactorial. Nevertheless, impaired angiogenesis is one potential component that might be common for many diabetic complications. Angiogenesis is a multi-stage process involving the endothelium, growth factors and their inhibitors, cytokines, endothelial progenitor cells (EPCs) and enzymes. Asfar as angiogenesis is concerned, diabetes is a paradoxical disease. An excessive angiogenesis is noted in retinopathy or nephropathy, while in diabetic foot syndrome the angiogenic response is insufficient