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Open access

Zdobyslaw Goraj

Abstract

This paper describes assumptions, goals, methods, results and conclusions related to fuel tank arrangement of a flying wing passenger airplane configuration. A short overview of various fuel tank systems in use today of different types of aircraft is treated as a starting point for designing a fuel tank system to be used on very large passenger airplanes. These systems may be used to move fuel around the aircraft to keep the centre of gravity within acceptable limits, to maintain pitch and lateral balance and stability. With increasing aircraft speed, the centre of lift moves aft, and for trimming the elevator or trimmer must be used thereby increasing aircraft drag. To avoid this, the centre of gravity can be shifted by pumping fuel from forward to aft tanks. The lesson learnt from this is applied to minimise trim drag by moving the fuel along the airplane. Such a task can be done within coming days if we know the minimum drag versus CG position and weight value. The main part of the paper is devoted to wing bending moment distribution. A number of arrangements of fuel in airplane tanks are investigated and a scenario of refuelling - minimising the root bending moments - is presented. These results were obtained under the assumption that aircraft is in long range flight (14 hours), CL is constant and equal to 0.279, Specific Fuel Consumption is also constant and that overall fuel consumption is equal to 20 tons per 1 hour. It was found that the average stress level in wing structure is lower if refuelling starts from fuel tanks located closer to longitudinal plane of symmetry. It can influence the rate of fatigue.

Open access

Chunya Sun, Baowei Song and Peng Wang

Abstract

Underwater glider, as a new kind of autonomous underwater vehicles, has many merits such as long-range, extended-duration and low costs. The shape of underwater glider is an important factor in determining the hydrodynamic efficiency. In this paper, a high lift to drag ratio configuration, the Blended-Wing-Body (BWB), is used to design a small civilian under water glider. In the parametric geometric model of the BWB underwater glider, the planform is defined with Bezier curve and linear line, and the section is defined with symmetrical airfoil NACA 0012. Computational investigations are carried out to study the hydrodynamic performance of the glider using the commercial Computational Fluid Dynamics (CFD) code Fluent. The Kriging-based genetic algorithm, called Efficient Global Optimization (EGO), is applied to hydrodynamic design optimization. The result demonstrates that the BWB underwater glider has excellent hydrodynamic performance, and the lift to drag ratio of initial design is increased by 7% in the EGO process.

Open access

Arash Kashani, Benjamin William Behrens Holman, Peter David Nichols and Aduli Enoch Othniel Malau-Aduli

Japanese Black cattle. BMC Genet., 9, p. 84; doi:10.1186/1471-2156-9-84; http://www.biomedcentral.com/1471-2156/9/84 Holman B.W.B., Kashani A., Malau- Aduli A.E.O. (2014 a). Effects of Spirulina (Arthrospira latensis) supplementation level and basal diet on liveweight, body conformation and growth traits in genetically divergent Australian dual-purpose lambs during simulated drought and typical pasture grazing. Small Rum. Res., 120: 6-14; doi http://dx.doi.org/10.1016/j.smallrumres.2014.04.014 Holman B.W.B., Kashani A., Malau- Aduli A

Open access

A Saeed, Malik. S. Raza and Ahmed Mohsin Khalil

,” AIAA Journal, Volume 46, No.6, June 2008, pp. 1442- 1452. 4. Qin, N., Wong, W.S., and Le Moigne, A., “Three-Dimensional Contour Bumps for Transonic Wing Drag Reduction,” ICAS 2000 Congress , pp. 2105, 1-10. Proc. IMechE Vol. 222 Part G: J. Aerospace Engineering, 2008, pp.619-629. 5. Sommerer, A., Lutz, T., and Wagner, S., “Numerical Optimization of Adaptive Transonic Airfoils with Variable Camber,” ICAS 2000 Congress , pp. 2111.1-2111.10. 6. Qin, N., Wong, W.S., and Le Moigne, A., “Adjoint-Based Optimization of a BWB Shape with Shock Control Bumps,” UKAA

Open access

Mahmoud Mohammadyan and Bijan Shabankhani

) Forschungsbericht FZKA-BWPLUS, Feinstaubbelastungen und deren gesundheitliche Wirkungen bei Kindern, in German] 2004 [displayed 10 Juni 2013]. Available at http://www.fachdokumente.lubw.baden-wuerttemberg.de/servlet/is/40191/BWB21007SBer.pdf?command=downloadContent&filename=BWB21007SBer.pdf 14. Son BS, Song MR, Yang WH. A Study on PM10 and VOCs concentrations of indoor environment in school and recognition of indoor air quality. In: from 10th International Conference on Indoor Air Quality and Climate; 4-9 Sep 2005. Beijing, China. Beijing: Tshinghua University

Open access

J. M. S. Gonzaga, R. O. Manoel, A. C. B. Sousa, A. P. Souza, M. L. T. Moraes, M. L. M. Freitas and A. M. Sebbenn

. Conservation Genetics Resources 1(1):465-469 Doyle J, Doyle J (1990) Isolation of DNA from small amounts of plant tissues. BRL focus 12:13-15 El-Kassaby Y, Funda T, Liewlaksaneeyanawin C (2015) Increasing Breeding without Breeding (BwB) Efficiency: Full-vs. Partial-Pedigree Reconstruction in Lodgepole Pine. SOJ Genet Sci 2(1):1-6 El-Kassaby YA, Funda T, Lai BS (2010) Female reproductive success variation in a Pseudotsuga menziesii seed orchard as revealed by pedigree reconstruction from a bulk seed collection. Journal of heredity 101

Open access

Michael Essig, Andreas H. Glas and Simon Mondry

), weiterer Abgeordneter und der Fraktion der SPD (Drucksache 17/2522). BWB (2011), Vorhaben SPz Puma - Darstellung der Fahrzeugpreisentwicklung von 12/2004 bis 2011, Koblenz 2011. Camp, R.C., (1989), Benchmarking: The search for industry best practices that lead to superior performance, Quality Resources, New York. Christensen, D.S./Searle, D.A./Vickery, C. (1999), The impact of the packard commission`s recommendations on reducing cost overruns on defense acquisition contracts, in: Acquisition Review Quarterly, Summer 1999

Open access

Kai Shiau, Te Hung Tsao and Chang Bin Yang

Hospital, Taiwan. Anthropometry Body height and mass of all participants were measured with an electronic stadiometer (Seca, Model 242, Hanover, MD) and digital scales (Tanita, Model BWB-627A, Hong Kong, China), respectively. The body mass index (BMI) was calculated by dividing body mass (kg) by body height (m) squared (kg/m 2 ). In addition, the body fat percentage (%) and fat-free mass (kg) were measured using an InBody 720 analyzer (BIOSPACE, Seoul, South Korea). The measurements were performed in the morning after an overnight fast. Maximal Strength