Mechanics and Applications of Pressure Adaptive Honeycomb

A pressure-adaptive wing structure is presented that relies on the pressure-altitude relation to adapt the wing shape to the various flight conditions (e.g. landing and cruise). This structure employs conventional, certified aerospace materials and can be implemented in aircraft ranging from LSA to business jets and high-subsonic transports. The adaptive structure consists of a honeycomb which has cells that extent a significant length perpendicular to the plane of the hexagons. In each cell resides a pouch (bladder) that can be pressurized. Pressurization yields a change in the stiffness of the structure. In combination with a restoring force, this structure shows strains in excess of 50% without any plastic deformation in the honeycomb cell walls. Mass specific energy densities for this pressure adaptive honeycomb is on the par with shape memory alloy, which has the highest mass specific energy density of the adaptive materials. A mathematical model based on the equivalent properties of the pressurized honeycomb is developed and verified against experimental tests. The applicability of this new adaptive structure is proven in the wind tunnel for a pressure adaptive flap on a generic wing section resulting in an increase in maximum lift coefficient of 0.3

Towards a hybrid comfortable passenger cabin interior for the flying V aircraft

The Flying-V is a V-shaped airplane in development, which uses less fuel due its form. Passengers are in the oval cabin in the wing, which asks for an alternative design to the interior. At the same time there is a demand for more comfortable interiors. 80 students were asked to develop interior design ideas for this Flying V concept. A jury of experts selected four aircraft interior concepts and these were developed and a 1:1 scale mockup was made, with a hybrid interior. It included a chaise longue seats, the group space, beds and ‘staggered’ seats for the middle of the Flying V interior. This was shown at a KLM 100 year event. 1692 visitors of the mock-up gave their preference and the chaise longue received most votes. In the discussions valuable comments from potential passengers were collected on the selected concepts giving input for further developments

GLOWOPT - A new approach towards global-warming-optimized aircraft design

A new concept for designing aircraft with minimum climate impact is presented. The paper describes the GLOWOPT approach, which is currently being implemented in the framework of the Clean Sky 2 programme. It aims at developing and validating so-called Climate Functions for Aircraft Design (CFAD). Those functions constitute an easy-to-use tool, which can be integrated into existing aircraft synthesis workflows without high adaptation effort. They will be made available to the relevant stakeholders including aircraft manufacturers, and thus allow for the development of new aircraft with a significantly reduced impact on global warming

Accelerating the path towards carbon-free aviation

This paper, created by a group of aviation and energy experts from renowned universities and research centres in Europe, who oversee the fields of energy carriers, energy storage and conversion, propulsion, aerodynamics, flight mechanics, controls, structures, materials, multidisciplinary design, and life‐cycle engineering, aims to give an overview and assessment of promising future technologies. The paper therefore identifies the potential as well as research demands of these technologies on the path to a sustainable and more environmentally friendly aviation

De houding van jongeren in detentie ten opzichte van sociale grenzen

Het verschil tussen jongeren met en zonder gedragsproblemen, ligt in de aan- of afwezigheid van observeerbaar gedrag dat zou kunnen worden aangemerkt als problematisch. De vraag is dan hoe dat verschil verklaard kan worden. In grote lijnen zijn er twee soorten verklaringen. Ten eerste, verklaringen die stellen dat de omstandigheden waaronder mensen opgroeien hen op het slechte pad brengen. Ten tweede, verklaringen die aannemen dat deviantie voortkomt uit een persoonlijkheidstrek, die de persoon aanzet tot het verwerpen en overtreden van sociale grenzen. Onzes inziens kan alleen een combinatie van beide noties een bevredigende verklaring van deviant gedrag opleveren. Daarom hebben we het probleern van beide kanten benaderd. Ten eerste trachtten wij de houding van jongeren ten opzichte van sociale grenzen te bestuderen door hun te vragen hoe ze zoude reageren als ze werden geconfronteerd met sociale grenzen en waarom ze zo zouden reageren. Ten tweede, achtten wij, op basis van de desbetreffende literatuur (vgl. Rink et al, 1989), de ecologie van deze houding van even groot belang. Dus hebben we geprobeerd te bepalen hoe deze jongeren hun leefomgeving waarderen, uitgaande van de stelling dat de subjectieve perceptie meer invloed heeft dan de objectieve ...omstandigheden zelf. Zie: Samenvatting

Airplane Design Optimization for Minimal Global Warming Impact

This paper presents a method to assess the key performance indicators of aircraft designed for minimum direct operating costs and aircraft designed for minimum global warming impact. The method comprises a multidisciplinary aircraft optimization algorithm capable of changing wing, engine, and mission design variables while including constraints on flight and field performance. The presented methodology uses traditional class-I methods augmented with dedicated class-II models to increase the sensitivity of the performance indicators to relevant design variables. The global warming impact is measured through the average temperature response caused by several emission species (including carbon dioxide, nitrogen oxides, and contrail formation) over a prolonged period of 100 years. The analysis routines are verified against experimental data or higher-order methods. The design algorithm is subsequently applied to a single-aisle medium-range aircraft, demonstrating that a 57% reduction in average temperature response can be achieved as compared to an aircraft optimized for minimal operating costs. This reduction is realized by flying at 7.6 km and Mach 0.60, and by lowering the engine overall pressure ratio to approximately 37. However, to compensate for the lower productivity, it is estimated that 13% more climate-optimized aircraft have to be operated for the hypothetical fleet under consideration