Journal articles: 'BWB'

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van Dommelen, Jorrit, and Roelof Vos. "Conceptual design and analysis of blended-wing-body aircraft." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 228, no. 13 (January 29, 2014): 2452–74. http://dx.doi.org/10.1177/0954410013518696.

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Due to the unconventional nature of the blended wing body (BWB) no off-the-shelf software package exists for its conceptual design. This study details a first step towards the implementation of traditional and BWB-specific design and analysis methods into a software tool to enable preliminary sizing of a BWB. The tool is able to generate and analyze different BWB configurations on a conceptual level. This paper investigates three different BWB configurations. The first configuration is an aft-swept BWB with aft-mounted engines, the second configuration is an aft-swept BWB with wing-mounted engines and the third configuration is a forward-swept BWB with wing-mounted engines. These aircraft comply with the same set of top-level requirements and airworthiness requirements. Each of the designs has been optimized for maximum harmonic range, while keeping its maximum take-off weight constant and identical. Results show that the forward-swept configuration with wing-mounted engines has the highest harmonic range. These findings warrant further investigation in this configuration and other alternative BWB configurations.

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Li, Jinglu, Peng Wang, Xu Chen, and Huachao Dong. "Shape Optimization of Blended-Wing-Body Underwater Gliders Based on Free-Form Deformation." Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 38, no. 3 (June 2020): 459–64. http://dx.doi.org/10.1051/jnwpu/20203830459.

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Currently developed underwater gliders can be roughly divided into the two types:traditional configuration and unconventional configuration. As a type of underwater gliders with unconventional configuration, a blended-wing-body (BWB) underwater glider has better fluid dynamic performances because of its unique shape. However, it is difficult to design the shape of the BWB underwater glider that has excellent hydrodynamic performances. Therefore, it is of great significance to optimize its shape, which this paper carries out by using the free-form deformation (FFD). The complete and automatic shape optimization framework is established by jointly using FFD parameterization method, CFD solver, optimization algorithm and mesh deformation method. The framework is used to optimize the shape of a BWB underwater glider. The average drag coefficient of the BWB underwater glider during its sinking and floating in one working period is used as the objective function to optimize its shape, with the volume constraints considered. The optimization results show that the gliding performance of the BWB underwater glider is remarkably enhanced.

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Zhang, Yong Jie, and Bin Tuan Wang. "Non-Cylindrical Fuselage Structural Optimization of BWB Civil Aircraft." Key Engineering Materials 474-476 (April 2011): 1736–39. http://dx.doi.org/10.4028/www.scientific.net/kem.474-476.1736.

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Blended-Wing-Body (BWB) civil aircraft possesses so light structure, high lift-drag ratio and low fuel burn that it has been an important topic of future civil aircraft. But internal pressure causes large bending stress instead of skin-membrane stress in BWB non-cylindrical fuselage. For 150 seats BWB fuselage, a composite 3-bay fuselage model is analyzed and two improved configurations of braced fuselage derivatives are designed in this paper. By optimization analysis, the optimized non-cylindrical fuselage structures are obtained in low bending stress and deformation condition, and optimized layer thicknesses ratio of composite material are presented. The optimization conclusions are very valuable and applicable for the fuselage structural design of BWB civil aircraft.

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Ignatov, S. D., and S. I. Tsekhosh. "ELASTIC CHARACTERISTICS OF BRUSH PILE ON THE MUNICIPAL MACHINE WORKING EQUIPMENT." Russian Automobile and Highway Industry Journal 16, no. 1 (March 1, 2019): 6–17. http://dx.doi.org/10.26518/2071-7296-2019-1-6-17.

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Introduction. The paper describes the actual problem of increasing the operating life of the brush working body (BWB) and improving the cleaning quality. Moreover, the authors discuss the factors affecting the quality of the road surface cleaning and the brush pile resource.Materials and methods. The research presents the results of the interaction process of the BWB pile with the cleaned surface of the roadway. In addition, the authors demonstrate the mathematical model of the interaction process with the basic surface. The simulation is carried out using the MATLAB software and Simulink extension. The authors also identify the factors that contribute the efficiency reduction of the municipal machine working process.Results. As a result of the simulation, the authors obtained the graphs of the pile deformation changing and the BWB pressing force changing. When processing the experimental data the researches also obtained the graphs of the brush pile plotted deformation from the BWB contact force and from 2, 3, 4 disks. For further mathematical modeling the authors determined the stiffness of the BWB pile under various loads. Therefore, the paper presents the approximation of the experimental dependence of the brush pile deformation on the pressing force and shows the regression equation.Conclusion. In conclusion, the authors determined the elastic characteristics of the BWB pile. By the comparing process of the experimental and theoretical data obtained from the mathematical model analysis, the authors found that the difference between them was less than 10%. The obtained results allowed confirming the mathematical model adequacy of the interaction process between the BWB pile and the cleaning surface.

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Panagiotou, Pericles, Thomas Dimopoulos, Stylianos Dimitriou, and Kyros Yakinthos. "Quasi-3D Aerodynamic Analysis Method for Blended-Wing-Body UAV Configurations." Aerospace 8, no. 1 (January 6, 2021): 13. http://dx.doi.org/10.3390/aerospace8010013.

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The current study presents a low-fidelity, quasi-3D aerodynamic analysis method for Blended-Wing-Body (BWB) Unmanned Aerial Vehicle (UAV) configurations. A tactical BWB UAV experimental prototype is used as a reference platform. The method utilizes 2D panel method analyses and theoretical aerodynamic calculations to rapidly compute lift and pitching moment coefficients. The philosophy and the underlying theoretical and semi-empirical equations of the proposed method are extensively described. Corrections related to control surfaces deflection and ground effect are also suggested, so that the BWB pitching stability and trimming calculations can be supported. The method is validated against low-fidelity 3D aerodynamic analysis methods and high-fidelity, Computational Fluid Dynamics (CFD) results for various BWB configurations. The validation procedures show that the proposed method is considerably more accurate than existing low-fidelity ones, can provide predictions for both lift and pitching moment coefficients and requires far less computational resources and time when compared to CFD modeling. Hence, it can serve as a valuable aerodynamics and stability analysis tool for BWB UAV configurations.

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WU, WENHUA, DEHUA CHEN, NING QIN, XIN PENG, and XINWU TANG. "A NEW EFFICIENT CONTROL METHOD FOR BLENDED WING BODY." International Journal of Modern Physics: Conference Series 19 (January 2012): 396–405. http://dx.doi.org/10.1142/s2010194512008999.

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The blended wing body (BWB) is the hottest one of the aerodynamic shapes of next generation airliner because of its' high lift-drag ratio, but there are still some flaws that cut down its aerodynamical performance. One of the most harmful flaws is the low efficiency of elevator and direction rudder, this makes the BWB hard to be controlled. In this paper, we proposed a new control method to solve this problem by morphing wing—that is, to control the BWB only by changing its wing shape but without any rudder. The pitching moments, rolling moments and yawing moments are plotted versus the parameters section and the wing shape in figures and are discussed in the paper. The result shows that the morphing wing can control the moments of BWB more precisely and in wider range. The pitching moments, rolling moments and yawing moments increases or decreases linearly or almost linearly, with the value of the selected parameters. These results show that using morphing wing is an excellent aerodynamic control way for a BWB craft.

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Dimopoulos, Thomas, Pericles Panagiotou, and Kyros Yakinthos. "Stability study and flight simulation of a blended-wing-body UAV." MATEC Web of Conferences 304 (2019): 02013. http://dx.doi.org/10.1051/matecconf/201930402013.

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This article is a product of the design process of a Blended-Wing- Body Unmanned Aerial Vehicle (BWB UAV). The BWB geometry blends the wing and the fuselage so that the fuselage also contributes in lift generation. This geometry reduces the lift to drag ratio significantly, however it also compromises the aircraft’s stability and controllability, since there is no horizontal and vertical tail. As these features are absent from the BWB layout, the need to incorporate their functions in the new geometry arises so that they cover stability demands sufficiently, according to aircraft of similar size, use and speed. Additionally, the method used for stability studies of conventional aircraft must also be adapted. This article covers the adaptation of the method to the new BWB geometry, its results in comparison to those of conventional aircraft and the use of the results for a computational simulation of the aircraft’ flight.

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Galea, E. R., L. Filippidis, Z. Wang, and J. Ewer. "Fire and evacuation analysis in BWB aircraft configurations: computer simulations and large-scale evacuation experiment." Aeronautical Journal 114, no. 1154 (April 2010): 271–77. http://dx.doi.org/10.1017/s0001924000003717.

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Abstract How long would it take to evacuate a blended wing body (BWB) aircraft with around 1,000 passengers and crew? How long would it take an external post-crash fire to develop non-survivable conditions within the cabin of a BWB aircraft? Is it possible for all the passengers to safely evacuate from a BWB cabin subjected to a post-crash fire? These questions are explored in this paper through computer simulation. As part of project NACRE, the airEXODUS evacuation model was used to explore evacuation issues associated with BWB aircraft and to investigate fire issues, the CFD fire simulation software SMARTFIRE was used. The fire and evacuation simulations were then coupled to investigate how the evacuation would proceed under the conditions produced by a post-crash fire. In conjunction with this work, a large-scale evacuation experiment was conducted in February 2008 to verify evacuation model predictions. This paper presents some of the results produced from this analysis.

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Ma, Yunlong, Guang Pan, Qiaogao Huang, and Jinglu Li. "Research on Hydrodynamic Characteristics of Blended Wing Body Underwater Glider with Rudder." Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 38, no. 1 (February 2020): 24–30. http://dx.doi.org/10.1051/jnwpu/20203810024.

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In order to improve the maneuverability and stability of the Blended Wing Body (BWB) underwater glider, the trailing edge rudder is integrated into its shape design in this paper. Through the numerical simulation of CFD, the variation laws of the hydraulic parameters such as lift, drag, lift-to-drag ratio with the angle of attack and rudder angle are given. Compared with the traditional underwater glider, the BWB underwater glider not only has high loading capacity, but also has a maximum lift-to-drag ratio three times that of the former, resulting in higher energy efficiency. At the same time, by adding trailing edge rudders, the maneuverability of the BWB underwater glider is improved, and the lift-to-drag ratio under the same large rudder angle is increased by more than 30% compared with the variable-wing underwater glider. Finally, through the analysis of the numerical results and the cloud image, the difference interaction extent between the rudder and the body of the BWB underwater glider and the traditional torpedo or AUV is illustrated.

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Marcone, C., K. S. Gibb, C. Streten, and B. Schneider. "‘Candidatus Phytoplasma spartii’, ‘Candidatus Phytoplasma rhamni’ and ‘Candidatus Phytoplasma allocasuarinae’, respectively associated with spartium witches'-broom, buckthorn witches'-broom and allocasuarina yellows diseases." International Journal of Systematic and Evolutionary Microbiology 54, no. 4 (July 1, 2004): 1025–29. http://dx.doi.org/10.1099/ijs.0.02838-0.

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Spartium witches'-broom (SpaWB), buckthorn witches'-broom (BWB) and allocasuarina yellows (AlloY) are witches'-broom and yellows diseases of Spartium junceum (Spanish broom), Rhamnus catharticus (buckthorn) and Allocasuarina muelleriana (Slaty she-oak), respectively. These diseases are associated with distinct phytoplasmas. The SpaWB, BWB and AlloY phytoplasmas share <97·5 % 16S rDNA sequence similarity with each other and with other known phytoplasmas, including the closely related phytoplasmas of the apple proliferation group. Also, the SpaWB, BWB and AlloY phytoplasmas each have a different natural plant host. Based on their unique properties, it is proposed to designate the mentioned phytoplasmas as novel ‘Candidatus’ species under the names ‘Candidatus Phytoplasma spartii’, ‘Candidatus Phytoplasma rhamni’ and ‘Candidatus Phytoplasma allocasuarinae’, respectively.

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Karpuk, Stanislav, Yaolong Liu, and Ali Elham. "Multi-Fidelity Design Optimization of a Long-Range Blended Wing Body Aircraft with New Airframe Technologies." Aerospace 7, no. 7 (June 30, 2020): 87. http://dx.doi.org/10.3390/aerospace7070087.

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The German Cluster of Excellence SE²A (Sustainable and Energy Efficient Aviation) is established in order to investigate the influence of game-changing technologies on the energy efficiency of future transport aircraft. In this paper, the preliminary investigation of the four game-changing technologies active flow control, active load alleviation, boundary layer ingestion, and novel materials and structure concepts on the performance of a long-range Blended Wing Body (BWB) aircraft is presented. The BWB that was equipped with the mentioned technologies was designed and optimized using the multi-fidelity aircraft design code SUAVE with a connection to the Computational Fluid Dynamics (CFD) code SU2. The conceptual design of the BWB aircraft is performed within the SUAVE framework, where the influence of the new technologies is investigated. In the second step, the initially designed BWB aircraft is improved by an aerodynamic shape optimization while using the SU2 CFD code. In the third step, the performance of the optimized aircraft is evaluated again using the SUAVE code. The results showed more than 60% reduction in the aircraft fuel burn when compared to the Boeing 777.

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Ali, Zurriati Mohd, Wahyu Kuntjoro, and Wisnoe Wirachman. "The Effect of Canard to the Aerodynamic Behavior of Blended Wing Body Aircraft." Applied Mechanics and Materials 225 (November 2012): 38–42. http://dx.doi.org/10.4028/www.scientific.net/amm.225.38.

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This paper presents a study on the effect of canard setting angle on the aerodynamic characteristic of a Blended Wing Body (BWB). Canard effects to BWB aerodynamic characteristics are not widely investigated. Hence the focus of the study is to investigate the variations of lifts, drags and moments when the angles of attack are varied at different canard setting angles. Wind tunnel tests were performed on BWB aircraft with canard setting angles,  ranging from -20˚ to 20˚. Angles of attack,  were varied from -10˚ to 10˚. Aspect ratio and canard planform area were kept fixed. All tests were conducted in the subsonic wind tunnel at Universiti Teknologi MARA, at Mach number of 0.1. The streamlines flow, at the upper surface of the canard was visualized using mini tuft. Result shows that the lift coefficient does not change much with different canard setting angles. As expected, the lift coefficient increases with increasing angles of attack at any canard setting angle. In general, the moment coefficient increases as the canard setting angle is increased. The results obtained in this research will be of importance to the understanding of aerodynamic behavior of BWB employing canard in its configuration.

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Petrovic, V. C., M. P. Petrovic, D. Ruzic-Muslic, N. Maksimovic, M. Selionova, M. M. Aybazov, and M. A. Malyukova. "Genotype, sex and interaction effect on lamb growth traits." Biotehnologija u stocarstvu 31, no. 1 (2015): 37–44. http://dx.doi.org/10.2298/bah1501037p.

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The pure breeds and crossing have an important role in production. It is essential in sheep meat production to maintain the genetic diversity of the adapted breeds, pure breeds and their crosses. Objective of the study is to determine the impact of genotype and sex on growth traits of lambs. Results of the study showed that male of all genotypes were dominant on body weight in all ages (from BWB to BW90). The highest birth weight (BWB) got male of genotype 2 (W). The lowest body weight at birth was the female lambs of genotype 1 (P). Body weights at ages 30, 60 and 90 days, male and female of genotype 4 (PxWxF) were dominant among other genotypes. Genotype 1 (P) of both sexes had the lowest bodyweights in all ages (BWB, BW30, BW60, BW90). The result showed better growth efficiency from males compared with females. The results of fixed factors and its impact on body weights of lambs showed very significant effect of genotype (P<0.01) on body weights of lambs at birth (BWB), ages 30, 60 and 90 days (BW30, BW60, BW90). The effect of sex had highly significant effects (P<0.001) on all ages. The interaction between genotype x sex showed a very significant effect (P?0.01) on body weight at birth (BWB) but were not significant (P?0.05) on body weights of lambs at ages BW30, BW60 and BW90. Superiority on growth traits of genotype 4 (PxWxF) at ages 30, 60 and 90 days, indicating that three-bred crossing resulted in high growth traits.

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Cai, Chen Fang, Yong Ming Qin, and Jiang Hao Wu. "The Effect of Belly-Flap on Aerodynamic Performance of Blended Wing Body Civil Aircraft." Applied Mechanics and Materials 378 (August 2013): 69–73. http://dx.doi.org/10.4028/www.scientific.net/amm.378.69.

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The effect of Belly-flap on aerodynamic performance of BWB civil aircraft are investigated in take-off and landing by computational fluid dynamics. And the overload of BWB with Belly-flap also is calculated in the same flight condition. Six parameters are discussed as design parameters of the Belly flap. It is shown that the proper combination of design parameters of Belly-flap can increase the maximum of lift and reduce the angle of attack and nose down moment to improve the flight safety in take-off and landing. When the aircraft with Belly-flap encounters the gust, the maximum overload is very close to 2.5 which are requested by FAR. It is suggested the optimized design of Belly-flap should be done if the Belly-flap is applied in BWB civil aircraft.

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Brown, Cecil H. "Evaluating proposals of language genealogical relationship." Language Dynamics and Change 7, no. 2 (2017): 252–85. http://dx.doi.org/10.1163/22105832-00702003.

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In an endeavor to objectify and provide uniformity to the comparative method of historical linguistics, this study describes the Beck-Wichmann-Brown (BWB) system for evaluating lexical sets assembled as evidence for proposals of language genealogical relationship. The approach quantitatively assesses the degree of support that collections of comparative sets provide for proposals, with regard to whether or not observed lexical similarity exceeds coincidental expectation. BWB is illustrated through application to an assemblage of 51 comparative sets compiled by Pache (2016) for the affiliation of Pumé and Chocoan languages of South America. This study presents and ranks BWB quantitative results for 65 language comparisons (of global distribution) and proposes a framework for interpreting ranked findings. Evaluations for the 65 comparisons are compared with those provided by three online classifications of the world’s languages.

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Ghani, M. Khairul Zaimy Abd, and Anika Zafiah Mohd Rus. "Influence of Hot Compression Moulding of Biopolymer Filled Waste Granulate Biopolymer." Applied Mechanics and Materials 315 (April 2013): 448–52. http://dx.doi.org/10.4028/www.scientific.net/amm.315.448.

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Bio-monomer based on original cooking oil was mixed with the hardeners with different percentages of Waste granulate Biopolymer (WB) fillers which is 30, 40, and 50 % equivalent to weight of monomer to produce Biopolymer filled Waste granulate Biopolymer (BWB) by using hot compress moulding. The tensile strength of BWB is 0.33, 0.45 and 0.43 MPa, meanwhile value of Youngs Modulus is 11.00, 8.18 and 5.06 MPa for loading 30, 40 and 50 % respectively. From the Scanning Electron Microscopy (SEM) micrograph, BWB has two characteristic and classified as a brittle and ductile fracture of granular (shiny) texture or cleavage character with little yielding before the sample breaks. Furthermore brittle fracture is characteristic by rapid crack propagation and then ductile fracture with stress whitening zone, appears fibrous appearance is dull and it have very rough surface. This fracture has glassy smooth surface, flat, bright, shiny and minimum deformation.

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Mohd Saad, Nornashiha, Wirachman Wisnoe, Rizal Effendy Mohd Nasir, Zurriati Mohd Ali, and Ehan Sabah Shukri Askari. "Aerodynamic Analysis of Blended Wing Body - Unmanned Aerial Vehicle (BWB-UAV) Equipped with Horizontal Stabilizers." MATEC Web of Conferences 256 (2019): 02004. http://dx.doi.org/10.1051/matecconf/201925602004.

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This paper presents an aerodynamic characteristic study in longitudinal direction of UiTM Blended Wing Body-Unmanned Aerial Vehicle Prototype (BWB-UAV Prototype) equipped with horizontal stabilizers. Flight tests have been conducted and as the result, BWB experienced overturning condition at certain angle of attack. Horizontal stabilizer was added at different location and size to overcome the issue during the flight test. Therefore, Computational Fluid Dynamics (CFD) analysis is performed at different configuration of horizontal stabilizer using Spalart - Allmaras as a turbulence model. CFD simulation of the aircraft is conducted at Mach number 0.06 or v = 20 m/s at various angle of attack, α. The data of lift coefficient (CL), drag coefficient (CD), and pitching moment coefficient (CM) is obtained from the simulations. The data is represented in curves against angle of attack to measure the performance of BWB prototype with horizontal stabilizer. From the simulation, configuration with far distance and large horizontal stabilizer gives steeper negative pitching moment slope indicating better static stability of the aircraft.

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Humphreys-Jennings, Clayton, Ilias Lappas, and Dragos Mihai Sovar. "Conceptual Design, Flying, and Handling Qualities Assessment of a Blended Wing Body (BWB) Aircraft by Using an Engineering Flight Simulator." Aerospace 7, no. 5 (April 28, 2020): 51. http://dx.doi.org/10.3390/aerospace7050051.

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The Blended Wing Body (BWB) configuration is considered to have the potential of providing significant advantages when compared to conventional aircraft designs. At the same time, numerous studies have reported that technical challenges exist in many areas of its design, including stability and control. This study aims to create a novel BWB design to test its flying and handling qualities using an engineering flight simulator and as such, to identify potential design solutions which will enhance its controllability and manoeuvrability characteristics. This aircraft is aimed toward the commercial sector with a range of 3000 nautical miles, carrying 200 passengers. The BWB design was flight tested at an engineering flight simulator to first determine its static stability through a standard commercial mission profile, and then to determine its dynamic stability characteristics through standard dynamic modes. Its flying qualities suggested its stability with a static margin of 8.652% of the mean aerodynamic chord (MAC) and consistent response from the pilot input. In addition, the aircraft achieved a maximum lift-to-drag ratio of 28.1; a maximum range of 4,581 nautical miles; zero-lift drag of 0.005; while meeting all the requirements of the dynamic modes.

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El-KASSABY, YOUSRY A., and MILAN LSTIBŮREK. "Breeding without breeding." Genetics Research 91, no. 2 (April 2009): 111–20. http://dx.doi.org/10.1017/s001667230900007x.

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SummaryAn innovative approach to tree breeding called ‘breeding without breeding’ (BWB) is presented. The method, as applied on the material in hand, allows the capture of 75–85% of the genetic response to selection attained through conventional programmes without the need to do any controlled pollination and simplified or possibly no experimental field testing: both considered to be the most resource-demanding activities in breeding programmes. BWB combines the use of genotypic or phenotypic pre-selection of superior individuals, informative DNA markers for fingerprinting and pedigree reconstruction of offspring to assemble naturally created full- and half-sib families resulting from mating among selected parents, and quantitative genetics analyses to identify elite genotypes for further genetic improvement or the establishment of production populations. BWB utility is demonstrated using a retrospective study of Douglas-fir (Pseudotsuga menziesii) progeny tests consisting of offspring produced from 150 controlled crosses among 60 parents and established over three sites. The empirical results are supported by theoretical expectations demonstrating anticipated minimum genetic response compared with conventional approaches. The method's simplicity offers an exceptional opportunity for the development of comparable breeding efforts in developing countries, advanced and new breeding programmes, and economically important and ‘minor’ species.

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Song, Yu, Jia Liu, and Qian Liu. "Dynamic Decision-Making Process of Evacuees during Post-Earthquake Evacuation near an Automatic Flap Barrier Gate System: A Broken Windows Perspective." Sustainability 13, no. 16 (August 5, 2021): 8771. http://dx.doi.org/10.3390/su13168771.

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The automatic flap barrier gate system (AFBGS) plays a critical role in building security, but it is more vulnerable to natural hazards than common exits (including power failure, due to earthquakes, and delayed evacuation, due to safety certification, etc.). This article considers a dynamic decision-making process of evacuees during post-earthquake evacuation near an AFBGS. An interesting metaphor, broken windows (BW), is utilized to interpret people’s actual behavior during evacuation. A multi-stage decision-making mechanism of evacuees is developed to characterize the instantaneous transition among three defined stages: Habitual, mild, and radical states. Then, we build a modified three-layer social force model to reproduce the interaction between evacuees based on an actual post-earthquake evacuation. The simulations reveal that BW provides a contextualized understanding of emergency evacuation with a similar effect to the traditional metaphor. An earlier appearance of a mild rule breaker leads to a higher crowd evacuation efficiency. If evacuees maintain the state of broken windows behavior (BWB), the crowd evacuation efficiency can be improved significantly. Contrary to the criminological interpretation, the overall effect of mild BWB is positive, but the radical BWB is encouraged under the command of guiders.

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Nasir, Rizal E. M., Wahyu Kuntjoro, Wisnoe Wirachman, and Zurriati Ali. "Longitudinal Flight Dynamics of Baseline-II BWB UAV." Advanced Materials Research 433-440 (January 2012): 6636–40. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.6636.

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The objective of this paper is to investigate longitudinal flight dynamics of the said aircraft at loitering flight condition near sea level. Three mathematical dynamic models are used to compute transient response of Baseline-II E-2 BWB along with a proposed model known as Model-N. Model-N is derived to incorporate as many important derivatives, including gravitational and pitch angle factor, as possible. While all these four dynamic models are different in a sense where one model is more simple or complex than the others, the basic architecture of all these models are the same. This paper shows the short-period mode needs serious attention. A control algorithm is needed to overcome its handicap which is below Level 3 damping ratio according to MIL-F-8785C. Improvement to phugoid can be considered secondary, but one must ensure that bringing short period mode to Level 1 flying quality does not make phugiod mode response worse than it is now.

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Hanis, Tomás, and Martin Hromcík. "Information-based sensor placement optimization for BWB aircraft." IFAC Proceedings Volumes 44, no. 1 (January 2011): 2236–41. http://dx.doi.org/10.3182/20110828-6-it-1002.00428.

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Kissoon, Sajal, Francesco Saverio Mastropierro, Devaiah K. Nalianda, Andrew Rolt, and Bobby Sethi. "Assessment of the BWB aircraft for military transport." Aircraft Engineering and Aerospace Technology 92, no. 5 (April 6, 2020): 769–76. http://dx.doi.org/10.1108/aeat-09-2019-0188.

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Purpose The growth in air mobility, rising fuel prices and ambitious targets in emission reduction are some of the driving factors behind research towards more efficient aircraft. The purpose of this paper is to assess the application of a blended wing body (BWB) aircraft configuration with turbo-electric distributed propulsion in the military sector and to highlight the potential benefits that could be achieved for long-range and heavy payload applications. Design/methodology/approach Mission performance has been simulated using a point-mass approach and an engine performance code (TURBOMATCH) for the propulsion system. Payload-range charts were created to compare the performance of a BWB aircraft with various different fuels against the existing Boeing 777-200LR as a baseline. Findings When using kerosene, an increase in payload of 42 per cent was achieved but the use of liquefied natural gas enabled a 50 per cent payload increase over a design range of 7,500 NM. When liquid hydrogen (LH2) is used, the range may be limited to about 3,000 NM by the volume available for this low-density fuel, but the payload at this range could be increased by 137 per cent to 127,000 kg. Originality/value The results presented to estimate the extent to which the efficiency of military operations could be improved by making fewer trips to transport high-density and irregular cargo items and indicate how well the proposed alternatives would compare with present military aircraft. There are no existing NATO aircraft with such extended payload and range capacities. This paper, therefore, explores the potential of BWB aircraft with turbo-electric distributed propulsion as effective military transports.

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Kumar, Ashutosh, and Raghvendra Gautam. "Design of Elevons, Wings, and Performance Investigation for A Blended Wing Body UAV." International Journal of Engineering and Advanced Technology 11, no. 1 (October 30, 2021): 60–69. http://dx.doi.org/10.35940/ijeat.a3152.1011121.

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Objectives: To study a hybrid VTOL- Blended wing body design for its wings and elevons and perform CFD simulations with the wings. The steps for designing wing configuration and Elevon positioning involve different variables giving rise to a large number of design possibilities for a control surface. In the current study methods, have been proposed for the selection of optimized wing configuration and elevons positioning and validated with simulations model. Methods: Meta-heuristic methods like genetic algorithms are used for arriving at favorable solutions and Matlab coding is written for the initial draft of wing geometry, selected geometries are iterated in XFLR5 for stability and control, and later validated with simulations around the fluid domain. Elevons are control surfaces generally installed in tailless aircraft at the wing's trailing edge. It applies to roll and pitching force to wings as it combines the functionality of both pitching and rolling control. Design space was mathematically plotted and solved using MATLAB to decide elevons, wing configuration, and their positions.Findings: Initial selection of wing geometry, aoa, and structural design for maneuverability and stability for the enhanced aerodynamic performance of BWB UAV. In this presented paper drag coefficient of the designed BWB UAV comes out to be precisely around 0.02216 using computational modeling. Variation curve of Lift and drag coefficient with aspect ratio and angle of attack. Post-processing results of pressure forces and velocity profile on Wings accurately validate the proposed method of control surface optimization. Novelty: Designed BWB UAV has increased lift to drag ratio, reduced weight of airframe which improves performance. The Design phase is highly iterative, Through this research paper, an attempt has been made to develop a methodology for selection and investigation of control surfaces against requirements that makes BWB UAV more helpful for practical use and increasing the lift and endurance efficiency of the hybrid VTOL- Blended wing body aircraft.

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Gustin, P., F. Lomba, J. Bakima, P. Lekeux, and K. P. Van de Woestijne. "Partitioning of pulmonary resistance in calves." Journal of Applied Physiology 62, no. 5 (May 1, 1987): 1826–31. http://dx.doi.org/10.1152/jappl.1987.62.5.1826.

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Nine right apical lobes of healthy Friesian calves and 10 right apical lobes of double-muscled calves of Belgian White and Blue (BWB) breed were suspended in an airtight box, inflated at a constant transpulmonary pressure (Ptp), and subjected to quasi-sinusoidal pressure changes (amplitude: 0.5 kPa) at a frequency of 30 cycles/min. Lobar resistance (RL) was partitioned at six different lung volumes into three components: central airway resistance (Rc), small airway resistance (Rp), and tissue resistance (Rt). Pressure in small airways (2–3 mm ID) was measured with a retrograde catheter. Alveolar pressure was sampled in capsules glued onto the punctured pleural surface. RL was minimal at values of Ptp comprised between 0.5 and 0.7 kPa and increased at higher and lower values of Ptp. At a Ptp of 0.5 kPa, Rc, Rp, and Rt represented 30, 15, and 55% of RL, respectively, in Friesian calves and 25, 25, and 50% in BWB calves. Rp increased markedly at low lung volumes. Rt was responsible for the increase of RL at high Ptp. Rc tended to decrease at high Ptp. The significantly higher values of Rp in BWB calves (P less than 0.05) might explain the sensitivity of this breed to severe bronchopneumonia.

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Zurriati, M. Ali, Kuntjoro Wahyu, Wirachman Wisnoe, and E. M. Nasir Rizal. "The Effect of Canard on Aerodynamics of Blended Wing Body." Applied Mechanics and Materials 110-116 (October 2011): 4156–60. http://dx.doi.org/10.4028/www.scientific.net/amm.110-116.4156.

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This paper describes the wind tunnel testing of a Blended Wing Body (BWB) with rectangular canards and twisted wing (Baseline II E2 configuration) developed in Universiti Teknologi MARA (UiTM). The experiment work was carried out in UiTM low speed wind tunnel using 1:6 scaled model of BWB at Mach 0.1. The testing is conducted for canard’s deflection angle between 0° to +20. The results show by adding the canard surface to the BWB’s body, at 12 degree and higher angles of attack,α there will be a slight increment in lift. Maximum lift-to-drag ratio decreases with increasing canard surface deflection. Also, by adding the canard surface, the value of moment at zero lift,CM,0 is increased.

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DANLOIS, Fabien, Shahparak ZALTASH, Jan JOHANSSON, Bengt ROBERTSON, Henk P. HAAGSMAN, Martin VAN EIJK, Michael F. BEERS, Frédéric ROLLIN, Jean-Marie RUYSSCHAERT, and Guy VANDENBUSSCHE. "Very low surfactant protein C contents in newborn Belgian White and Blue calves with respiratory distress syndrome." Biochemical Journal 351, no. 3 (October 24, 2000): 779–87. http://dx.doi.org/10.1042/bj3510779.

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We have studied a respiratory distress syndrome (RDS) occurring in newborn calves of the Belgian White and Blue (BWB) breed that represents the large majority of beef cattle in Belgium. Pulmonary surfactant isolated from 14 BWB newborn calves that died from RDS and from 7 healthy controls was analysed for composition and surface activity. An extremely low content or, in some instances, an absence of surfactant protein C (SP-C) was detected in the RDS samples by Western blotting and differential amino acid analysis [0.03±0.01% (w/w) relative to total phospholipids, compared with 0.39±0.06% for healthy controls (means±S.E.M., P < 0.001)]. The contents of surfactant protein B (SP-B) were similar in RDS and control samples. The crude surfactant samples isolated from RDS calves had higher ratios of total protein to total phospholipid, altered phospholipid profiles and lower SP-A contents. Both crude and organic extracts of RDS surfactant samples showed increased dynamic surface tension compared with healthy controls when evaluated with a pulsating-bubble surfactometer. The addition of purified SP-C to organic extracts of RDS surfactant samples lowered surface tension. Strongly decreased levels of mature SP-C associated with fatal RDS and altered surface activity in vitro have, to the best of our knowledge, not been previously reported. The mechanisms underlying RDS and the decrease in SP-C in BWB calves remain to be established.

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Hanis, Tomás, and Martin Hromcík. "Lateral control for flexible BWB high-capacity passenger aircraft." IFAC Proceedings Volumes 44, no. 1 (January 2011): 7233–37. http://dx.doi.org/10.3182/20110828-6-it-1002.00427.

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Goraj, Zdobyslaw. "Design and Optimisation of Fuel Tanks for BWB Configurations." Archive of Mechanical Engineering 63, no. 4 (December 1, 2016): 605–17. http://dx.doi.org/10.1515/meceng-2016-0034.

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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.

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Schirrer, A., C. Westermayer, M. Hemedi, and M. Kozek. "Actuator and Sensor Positioning Optimization in Control Design for a Large BWB Passenger Aircraft." ISRN Mechanical Engineering 2011 (June 26, 2011): 1–11. http://dx.doi.org/10.5402/2011/635815.

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This paper states an approach to actuator and sensor positioning optimization and design in the control system design of a large blended wing body (BWB) passenger aircraft. Numerous objectives have to be achieved by the control system: loads alleviation, vibration attenuation, and the fulfillment of handling quality requirements. Exploiting the system structure and existing system knowledge (excitation, comfort, and load formulations), evaluation criteria are designed to assess actuator and sensor effectiveness and efficiency for the aircraft dynamic range of interest. The tasks of optimal actuator and sensor positioning, actuator sizing, and actuator bandwidth requirements are investigated, whereby solutions that are robust are sought with respect to parameter variations. The results are shown on a BWB passenger aircraft model and verified using a normalized closed-loop performance assessment approach.

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Gu, Minfeng, and Y. L. Ai. "The optical variability of radio-loud quasars." Proceedings of the International Astronomical Union 8, S290 (August 2012): 217–18. http://dx.doi.org/10.1017/s1743921312019692.

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AbstractThe optical variability of a sample of 44 FSRQs and 18 SSRQs in the SDSS stripe 82 region is investigated by using the multi-epoch data covering nine years. The variabilities are clearly detected in each source with the amplitude in r band, from 0.18 to 3.46 mag. Twenty-five of 44 FSRQs show a bluer-when-brighter trend (BWB), while only one FSRQ shows a redder-when-brighter trend, which is in contrast to our previous results. Eight of 18 SSRQs display a BWB. We found an anti-correlation between the Eddington ratio and the variability amplitude in r band for SSRQs, which is similar to that in radio-quiet AGNs. This implies that the thermal emission from the accretion disk may be responsible for the variability in SSRQs.

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32

Moigne, A. Le, and N. Qin. "Aerofoil profile and sweep optimisation for a blended wing-body aircraft using a discrete adjoint method." Aeronautical Journal 110, no. 1111 (September 2006): 589–604. http://dx.doi.org/10.1017/s0001924000001457.

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Abstract Aerodynamic optimisations of a blended wing-body (BWB) aircraft are presented. A discrete adjoint solver is used to calculate efficiently the gradients, which makes it possible to optimise for a large number of design variables. The optimisations employ either a variable-fidelity method that combines low- and high-fidelity models or a direct sequential quadratic programming (SQP) method. Four Euler optimisations of a BWB aircraft are then presented. The optimisation is allowed to change a series of master sections defining the aircraft geometry as well as the sweep angle on the outer wing for two of the optimisations. Substantial improvements are obtained, not only in the Euler mode but also when the optimised geometries are evaluated using Reynolds-averaged Navier-Stokes solutions. Some interesting features of the optimised wing profiles are discussed.

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Mat, Shabudin, I. Shah Ishak, Khidzir Zakaria, and Z. Ajis Khan. "Manufacturing Process of Blended Delta-Shaped Wing Model." Advanced Materials Research 845 (December 2013): 971–74. http://dx.doi.org/10.4028/www.scientific.net/amr.845.971.

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Aerodynamicists have long acknowledged the blended wing body (BWB) aircraft design could produce great aerodynamic advantages due to the integration of the delta wing structure with the thick center body. Therefore the wind tunnel test campaign is crucial to gain information of the flow field that governs the delta-shaped wing which has frequently baffled the aerodynamicists. In such, the wind tunnel test required acceptable quality of delta-shaped wing model for results validity. Consequently, the manufacturing process as well as the selection of the appropriate machinery tools, must be wisely designed and performed. The modular 3D concept in associating with CAD/CAM technology was utilised in the process. Finally, the actual flow cycle of manufactures blended BWB aircraft model was sucessfully established. The objective of this paper is to highlight those complexity manufacturing process and techniques involved in order to produce a good blended delta-shaped wind tunnel model.

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34

Fürlinger, Sarah, and Maximilian Diem. "42. Competition Talk der BWB zum Thema „Blockchain und Kartellrecht“." Österreichische Zeitschrift für Kartellrecht 12, no. 2 (2019): 73. http://dx.doi.org/10.33196/oezk201902007301.

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35

Becka, Marcus. "40. Competition Talk der BWB zum Thema „Compliance und Kartellrecht“." Österreichische Zeitschrift für Kartellrecht 12, no. 3 (2019): 83. http://dx.doi.org/10.33196/oezk201903008301.

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36

Ivanova, Alexandra, and Sigrid Tresnak. "41. Competition Talk der BWB zum Thema „Schiedsgerichtsbarkeit und Wettbewerb“." Österreichische Zeitschrift für Kartellrecht 12, no. 3 (2019): 89. http://dx.doi.org/10.33196/oezk201903008901.

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37

Schirrer, A., C. Westermayer, M. Hemedi, and M. Kozek. "Robust convex lateral feedback control synthesis for a BWB aircraft." IFAC Proceedings Volumes 44, no. 1 (January 2011): 7262–67. http://dx.doi.org/10.3182/20110828-6-it-1002.01543.

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38

Yu, Gang, Dong Li, and Zeyu Zhang. "Simulation on Powered Effects of BWB at Take-off Condition." Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University 38, no. 2 (April 2020): 231–37. http://dx.doi.org/10.1051/jnwpu/20203820231.

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The influence of engine powered effects on aerodynamic characteristics of BWB300, which was designed by the Airplane Concept Design Institute of Northwestern Polytechnical University, at take-off condition was analyzed by using the numerical simulation method. Firstly, the method of using the inlet and exhaust boundary conditions to analyze the powered engine was validated. Then, the engine powered effects on BWB300 aerodynamic characteristics at take-off condition were researched with flow through nacelle and with powered nacelle. The results indicated that though the powered effect changing the value of aerodynamic forces, there was no change in the aerodynamic curve trend. It's recommended that the engine power effect should be considered in numerical simulation by using with powered nacelle to gain more accurate values of aerodynamic forces. Nevertheless, with flow nacelle also could be used to gain some regular results.

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39

Ban, Seokhyun, Jihyeong Lee, Sangwook Kim, and Jinsoo Cho. "Effects of Wing Twist on Longitudinal Stability of BWB UCAV." Journal of the Korean Society for Aeronautical & Space Sciences 46, no. 1 (January 31, 2018): 1–9. http://dx.doi.org/10.5139/jksas.2018.46.1.1.

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40

Jo, Young-Hee, Kyoungsik Chang, Dong-Jin Sheen, and Soo Hyung Park. "CFD Analysis of Aerodynamic Characteristics of a BWB UCAV configuration with Transition effect." Journal of the Korean Society for Aeronautical & Space Sciences 42, no. 7 (July 1, 2014): 535–43. http://dx.doi.org/10.5139/jksas.2014.42.7.535.

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41

Cook, M. V., and H. V. de Castro. "The longitudinal flying qualities of a blended-wing-body civil transport aircraft." Aeronautical Journal 108, no. 1080 (February 2004): 75–84. http://dx.doi.org/10.1017/s0001924000005029.

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Abstract This paper describes an evaluation of the longitudinal flying qualities of a generic blended-wing-body (BWB) transport aircraft at low speed flight conditions. Aerodynamic data was obtained from several sources and integrated into the equations of motion of a typical BWB configuration in order to provide a reasonable basis for flying qualities assessment. The control requirements to trim are enumerated for a representative range of cg position and static margin over the typical range of approach speeds for both stable and unstable configurations. The linear dynamic characteristics of the unaugmented airframe are also described for the same range of stability margin. Subsequent work describes the development of a rate command-attitude hold command and stability augmentation system configured to comply with representative modern handling criteria. Finally, the flight dynamics of the augmented aircraft are described after refinement of the control law by means of piloted simulation in a fixed base flight simulator.

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42

Sgueglia, Alessandro, Peter Schmollgruber, Emmanuel Benard, Nathalie Bartoli, and Joseph Morlier. "Preliminary Sizing of a Medium Range Blended Wing-Body using a Multidisciplinary Design Analysis Approach." MATEC Web of Conferences 233 (2018): 00014. http://dx.doi.org/10.1051/matecconf/201823300014.

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The aviation's goal for the next decades is to drastically reduce emissions, but to achieve this goal a breakdown in aircraft design has to be considered. One of the most promising concepts is the Blended Wing- Body, which integrates aerodynamics, propulsion and structure, and has a better aerodynamics efficiency, thanks to the reduction of the wetted surfaces. In this work the feasibility of a short/medium range BWB with 150 passengers (A320 Neo type aircraft, Entry Into Service 2035) is studied, considering different disciplines into the sizing process. The design loop has been reviewed to consider the unconventional concept. Also certification aspects have been taken into account in an off-design analysis. To evaluate the advantages of the proposed concept, it has been compared with an aircraft of the same class, the A320 Neo, resized to match the EIS2035 hypothesis: results show that the BWB is a concept that demonstrates a gain in fuel consumption, especially on longer ranges.

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43

Wang, Shusen, Yan Yang, Alexander P. Trishchenko, Alan G. Barr, T. A. Black, and Harry McCaughey. "Modeling the Response of Canopy Stomatal Conductance to Humidity." Journal of Hydrometeorology 10, no. 2 (April 1, 2009): 521–32. http://dx.doi.org/10.1175/2008jhm1050.1.

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Abstract Humidity of air is a key environmental variable in controlling the stomatal conductance (g) of plant leaves. The stomatal conductance–humidity relationships employed in the Ball–Woodrow–Berry (BWB) model and the Leuning model have been widely used in the last decade. Results of independent evaluations of the two models vary greatly. In this study, the authors develop a new diagnostic parameter that is based on canopy water vapor and CO2 fluxes to assess the response of canopy g to humidity. Using eddy-covariance flux measurements at three boreal forest sites in Canada, they critically examine the performance of the BWB and the Leuning models. The results show that the BWB model, which employs a linear relationship between g and relative humidity (hs), leads to large underestimates of g when the air is wet. The Leuning model, which employs a nonlinear function of water vapor pressure deficit (Ds), reduced this bias, but it still could not adequately capture the significant increase of g under the wet conditions. New models are proposed to improve the prediction of canopy g to humidity. The best performance was obtained by the model that employs a power function of Ds, followed by the model that employs a power function of relative humidity deficit (1 − hs). The results also indicate that models based on water vapor pressure deficit generally performed better than those based on relative humidity. This is consistent with the hypothesis that the stomatal aperture responds to leaf water loss because water vapor pressure deficit rather than relative humidity directly affects the transpiration rate of canopy leaves.

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Mohamad, Firdaus, Wisnoe Wirachman, Wahyu Kuntjoro, and Rizal E. M. Nasir. "The Effects of Split Drag Flaps on Directional Motion of UiTM’s BWB UAV Baseline-II E-4: Investigation Based on CFD Approach." Advanced Materials Research 433-440 (January 2012): 584–88. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.584.

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This paper presents a study about split drag flaps as control surfaces to generate yawing motion of a blended wing body aircraft. These flaps are attached on UiTM’s Blended Wing Body (BWB) Unmanned Aerial Vehicle (UAV) Baseline-II E-4. Deflection of split drag flaps on one side of the wing will produce asymmetric drag force and, as consequences, yawing moment will be produced. The yawing moment produced will rotate the nose of the BWB toward the wing with deflected split drag flaps. The study has been carried out using Computational Fluid Dynamics to obtain aerodynamics data with respect to various sideslip angles (ß). The simulation is running at 0.1 Mach number or about 35 m/s. Results in terms of dimensionless coefficient such as drag coefficient (CD), side force coefficient (CS) and yawing moment coefficient (Cn) are used to observe the effects of split drag Subscript text flaps on the yawing moment. All the results obtained shows linear trends for all curves with respect to sideslip angles (ß).

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45

Wong, W. S., A. Le Moigne, and N. Qin. "Parallel adjoint-based optimisation of a blended wing body aircraft with shock control bumps." Aeronautical Journal 111, no. 1117 (March 2007): 165–74. http://dx.doi.org/10.1017/s0001924000004425.

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An Euler optimisation for a BWB configuration with winglets incorporating an array of three-dimensional shock control bumps is carried out by employing an efficient adjoint-based optimisation methodology. A high fidelity multi-block grid with over two million grid points is generated to resolve the shape of the 3D shock control bumps, the winglet as well as the overall BWB shape, which are parameterised by over 650 design variables. In order to perform such a large aerodynamic optimisation problem feasibly, the optimisation tools such as the flow solver and the adjoint solver have to be parallelised with a good parallel efficiency. This paper reports the parallel implementation efforts on the adjoint solver; especially on the calculation of the sensitivity derivatives, which has to be looped over the total number of design variables. Results from the optimisation of the wing master sections, winglet aerofoil sections and the three dimensional bumps indicate a significant improvement regarding the aerodynamic performance against the baseline geometry for the given planform layout of the aircraft.

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46

Lee, Sea-Wook, Jin-Yeol Yang, and Jin-Soo Cho. "Aerodynamic Analysis of an Arbitrary Three-Dimensional Blended Wing Body Aircraft using Panel Method." Journal of the Korean Society for Aeronautical & Space Sciences 37, no. 11 (November 1, 2009): 1066–72. http://dx.doi.org/10.5139/jksas.2009.37.11.1066.

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47

Mohamad, Firdaus, Wirachman Wisnoe, Rizal E. M. Nasir, Khairul Imran Sainan, and Norhisyam Jenal. "Yaw Stability Analysis for UiTM's BWB Baseline-II UAV E-4." Applied Mechanics and Materials 393 (September 2013): 323–28. http://dx.doi.org/10.4028/www.scientific.net/amm.393.323.

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This paper presents a study about yaw stability analysis for UiTMs Blended-Wing-Body (BWB) Baseline-II E-4. This aircraft is equipped with split drag flaps in order to perform directional motion. One of the split drag flaps will be deflected to generate yawing moment. This yawing moment is generated through the drag that is produced upon deflection of flaps. The study was carried out using Computational Fluid Dynamics (CFD) for various sideslip angles (β) and various flaps deflection angle (δT). The simulation was conducted at 0.1 Mach number (35 m/s) and results in terms of coefficient such yawing and rolling moment are tabulated in order to determine the stability of the aircraft. The result reveals that the aircraft is directionally unstable. This is as expected because the aircraft does not have any vertical tail configuration to provide the yawing moment. However, high deflection of split flaps can still generate adequate restoring moment for the aircraft.

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Becka, Marcus. "38. Competition Talk der BWB zum Thema „Wettbewerb entlang der Wertschöpfungskette“." Österreichische Zeitschrift für Kartellrecht 12, no. 1 (2019): 29. http://dx.doi.org/10.33196/oezk201901002901.

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Becka, Marcus. "39. Competition Talk der BWB zum Thema „Aktuelle Entwicklungen im Kartellrecht“." Österreichische Zeitschrift für Kartellrecht 12, no. 2 (2019): 68. http://dx.doi.org/10.33196/oezk201902006801.

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Claudia Alice, STATE. "A Linear Analysis of a Blended Wing Body (BWB)Aircraft Model." INCAS BULLETIN 3, no. 3 (September 16, 2011): 115–26. http://dx.doi.org/10.13111/2066-8201.2011.3.3.12.

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Journal articles on the topic 'BWB'

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