The Influence of Demoiselle Aircraft on Light and General Aviation Design

In 1907, aviation pioneer Santos-Dumont had the idea of building a very light airplane. He designed and built the SD19, the \ud Demoiselle, an aircraft with a 6 meter wing span and a 24 HP engine of his own design. The Demoiselle was very successful in flying \ud and, became very popular and its development continued as SD20, SD21 and SD22 (his last airplane). The influence of the Demoiselle \ud on design principles of light aircraft and general aviation were studied in this work, using statistical entropy. The designs number 20 \ud and 22 may be considered dominant and influenced the design principles of light aircraft and general aviation

LOW BPR TURBOFAN PERFORMANCE WITH POWER EXTRACTION

Military aircraft require more electrical power than they used to do. The increased power consumption is dueto a transition from pneumatic and hydraulic systems to electrical and the introduction of new, more powerconsuming equipment. This paper summarizes an engine performance study, performed with a modeled lowbypass ratio mixed flow turbofan engine, where power is extracted from the low-pressure shaft, the highpressureshaft or a combination of the two. High-pressure shaft power extraction results in a considerableturbine inlet temperature increase. If the operating point has sufficient margin to the maximum turbine inlettemperature limit and if the power extraction is acceptable from an operability point of view, power can beextracted from the high-pressure shaft without causing much penalty on engine thrust. If the engine is runningclose to its maximum turbine inlet temperature, which is typically the case at low altitude and high aircraftspeed, power extraction from the low-pressure shaft could be a better alternative due to the lower turbine inlettemperature increase. This gives a higher margin to the maximum turbine inlet temperature limit. However, ifthe full potential of low-pressure shaft power extraction is to be utilized, the high-pressure compressor musthave some aerodynamic overspeed margin for the low-pressure shaft power extraction case. At part power,the lower specific thrust of the low-pressure shaft extraction case compared to the high-pressure shaft powerextraction case, is favorable from a propulsive efficiency and fuel consumption perspective

What is Missing for Traditional Design-Centric Engineering Education to Better Prepare Newly Graduated Engineers for the Global Era?

This paper presents an analysis of the capacity of design centric methodologies to prepare engineering students to succeed in the market. Gaps are brainstormed and analyzed with reference to their importance. Reasons that may lead the newly graduated engineers not to succeed right from the beginning of their professional lives have also been evaluated. A comparison among the two subjects above was prepared, reviewed and analyzed. The influence of multidisciplinary, multicultural and complex environmental influences created in the current global business era is taken into account. The industry requirements in terms of what they expect to 'receive' from their engineers are evaluated and compared to the remaining of the study above. An innovative approach to current engineering education that utilizes traditional design-centric methodologies is then proposed, aggregating new disciplines to supplement the traditional engineering education. The solution encompasses the inclusion of disciplines from Human Sciences and Emotional Intelligence fields willing to better prepare the engineer of tomorrow to work in a multidisciplinary, globalized, complex and team working environment. A pilot implementation of such an approach is reviewed and conclusions are drawn from this educational project

Analysis of a semi-empirical leading-edge slat noise prediction model

In this paper semi-empirical formulas are presented that relate macroscopic flow parameters observed in the slat cove and semi-empirical constants proposed in Guo’s semianalytical model. Fourteen slat configurations were simulatedusing the Lattice Boltzmann Method (LBM) implemented in PowerFLOWR commercial software. These results show an elementary relation between the four semiempirical constants proposed in Guo’s slat model and importantflow parameters, e.g., the shear-layer path length and the maximum shear velocity. Consequently, those four semi-empirical constants were rewritten in terms of two empirical constants which values can be derived fromRANS simulations. The proposed noise prediction model is consequently validated against wind tunnel aeroacoustics tests performed with the 30P30N high-lift device model. Experiments performed in the UTwente AeroacousticWind Tunnel at Rec = 1 x 106 and M = 0.15 showed good overall agreement between noise measurements and the proposed slat noise prediction model

What is Missing for Traditional Design-Centric Engineering Education to Better Prepare Newly Graduated Engineers for the Global Era?

This paper presents an analysis of the capacity of design centric methodologies to prepare engineering students to succeed in the market. Gaps are brainstormed and analyzed with reference to their importance. Reasons that may lead the newly graduated engineers not to succeed right from the beginning of their professional lives have also been evaluated. A comparison among the two subjects above was prepared, reviewed and analyzed. The influence of multidisciplinary, multicultural and complex environmental influences created in the current global business era is taken into account. The industry requirements in terms of what they expect to 'receive' from their engineers are evaluated and compared to the remaining of the study above. An innovative approach to current engineering education that utilizes traditional design-centric methodologies is then proposed, aggregating new disciplines to supplement the traditional engineering education. The solution encompasses the inclusion of disciplines from Human Sciences and Emotional Intelligence fields willing to better prepare the engineer of tomorrow to work in a multidisciplinary, globalized, complex and team working environment. A pilot implementation of such an approach is reviewed and conclusions are drawn from this educational project

AEROFOTOGRAFIAS DE BAIXO CUSTO COMO INSTRUMENTO DE MONITORAMENTO AMBIENTAL

RESUMO Atualmente, utilizam-se fotos aéreas obtidas de aviões equipados com câmaras especiais e "spots" conseguidos através de satélites de sensoriamento remoto. A proposta deste trabalho é utilizar-se um foguete de pequeno porte com alcance de 2.000m cuja carga útil é uma câmara fotográfica de 35mm com capacidade de 40 fotos. A câmara é abandonada no ponto mais alto da trajetória e retorna ao solo amparada por um pára-quedas, no período de queda, quando um circuito eletrônico dispara a câmara com intervalos controlados estabelecendo, assim, a escala da seqüência de fotos

ESTUDO EXPERIMENTAL SOBRE PONTAS DE ASA PARA UMA AERONAVE AGRÍCOLA

RESUMO O arrasto induzido em uma aeronave pode ser reduzido modificando-se suas pontas de asa. Alguns modelos de pontas de asa deslocam os vórtices para fora, diminuindo o arrasto induzido. Tratando-se de aviões agrícolas, que efetuam a deposição de defensivos sobre plantações, em vôo rasante, deslocamentos do vórtice são fundamentais para o aumento na eficiência da pulverização. Neste trabalho, efetuaram-se ensaios em túnel de vento para o estudo da influência que alguns tipos de pontas de asa podem ocasionar no desempenho de um avião agrícola. As pontas de asa ensaiadas foram: 'delta tip', 'winglet' e 'curvada para baixo'. A 'delta tip' apresenta moderado benefício aerodinâmico e bom posicionamento do vórtice para aplicação agrícola, enquanto a 'winglet' demonstra razoável benefício aerodinâmico e bom posicionamento do vórtice, mas prejuízo estrutural. A ponta de asa 'curvada para baixo' apresenta bom desempenho aerodinâmico; entretanto, posição do vórtice é inadequada para uso agrícola. Dentre estas, a ponta 'delta tip' é bastante promissora para emprego em uma aeronave agrícola

Termografia Aplicada à Visualização de Transição de Camada Limite em Aerofólios

A indústria aeronáutica tem grande interesse no estudo dos fluxos aerodinâmicos laminares, uma vez que produzem força de arrasto reduzida, resultando em economia de combustível nas aeronaves. Esse tipo escoamento em torno de superfícies aerodinâmicas e sua transição a turbulento torna-se, portanto, importante para o projeto aeronáutico e validação de modelos de Dinâmica dos Fluidos Computacional (CFD). No entanto, tal determinação apresenta dificuldades experimentais, muitas vezes relacionadas com métodos invasivos, que podem influenciar a camada limite do escoamento na superfície, tornando os dados não-representativos. Este artigo apresenta uma metodologia para determinar a transição da camada limite de laminar a turbulento usando câmeras de imageamento infravermelho de alta sensibilidade. Este método baseia-se no fato de que uma diferença de temperatura na superfície do perfil aerodinâmico sob escoamento laminar e turbulento é induzida por uma diferença na troca de calor entre os dois regimes: a troca de calor é maior em escoamentos turbulentos e pode ser detectada por estas câmeras. A principal vantagem deste método está no fato de que é não-invasivo e, portanto, fornece dados experimentais mais consistentes a fim de validar modelos teóricos com melhor precisão. O trabalho baseia-se em uma apresentação teórica dos conceitos aplicados e ensaios em túnel de vento conduzidos no Laboratório de Aerodinâmica da Escola de Engenharia de São Carlos - USP, por membros desta instituição, em conjunto com pesquisadores da Bombardier Aviation e Universidade Federal de São Carlos - UFSCar.</p