Download or read book Blended Wing Body Systems Studies written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-27 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: A CFD analysis was performed on a Blended Wing Body (BWB) aircraft with advanced, turbofan engines analyzing various inlet configurations atop the aft end of the aircraft. The results are presented showing that the optimal design for best aircraft fuel efficiency would be a configuration with a partially buried engine, short offset diffuser using active flow control, and a D-shaped inlet duct that partially ingests the boundary layer air in flight. The CFD models showed that if active flow control technology can be satisfactorily developed, it might be able to control the inlet flow distortion to the engine fan face and reduce the powerplant performance losses to an acceptable level. The weight and surface area drag benefits of a partially submerged engine shows that it might offset the penalties of ingesting the low energy boundary layer air. The combined airplane performance of such a design might deliver approximately 5.5% better aircraft fuel efficiency over a conventionally designed, pod-mounted engine.Geiselhart, Karl A. (Technical Monitor) and Daggett, David L. and Kawai, Ron and Friedman, DougLangley Research CenterACTIVE CONTROL; BLENDED-WING-BODY CONFIGURATIONS; COMPUTATIONAL FLUID DYNAMICS; ENGINE INLETS; FLOW DISTRIBUTION; INGESTION (ENGINES); DRAG; INLET FLOW; TURBOFAN ENGINES; ENGINE DESIGN; AIRCRAFT PERFORMANCE; PRESSURE RATIO; EXHAUST EMISSION; CONTAMINANTS; VORTEX GENERATORS...

Download or read book Blended Wing Body Systems Studies written by Karl A. Geiselhart and published by BiblioGov. This book was released on 2013-07 with total page 42 pages. Available in PDF, EPUB and Kindle. Book excerpt: A CFD analysis was performed on a Blended Wing Body (BWB) aircraft with advanced, turbofan engines analyzing various inlet configurations atop the aft end of the aircraft. The results are presented showing that the optimal design for best aircraft fuel efficiency would be a configuration with a partially buried engine, short offset diffuser using active flow control, and a D-shaped inlet duct that partially ingests the boundary layer air in flight. The CFD models showed that if active flow control technology can be satisfactorily developed, it might be able to control the inlet flow distortion to the engine fan face and reduce the powerplant performance losses to an acceptable level. The weight and surface area drag benefits of a partially submerged engine shows that it might offset the penalties of ingesting the low energy boundary layer air. The combined airplane performance of such a design might deliver approximately 5.5% better aircraft fuel efficiency over a conventionally designed, pod-mounted engine.

Download or read book Modeling and Control for a Blended Wing Body Aircraft written by Martin Kozek and published by Springer. This book was released on 2014-10-27 with total page 308 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book demonstrates the potential of the blended wing body (BWB) concept for significant improvement in both fuel efficiency and noise reduction and addresses the considerable challenges raised for control engineers because of characteristics like open-loop instability, large flexible structure, and slow control surfaces. This text describes state-of-the-art and novel modeling and control design approaches for the BWB aircraft under consideration. The expert contributors demonstrate how exceptional robust control performance can be achieved despite such stringent design constraints as guaranteed handling qualities, reduced vibration, and the minimization of the aircraft’s structural loads during maneuvers and caused by turbulence. As a result, this innovative approach allows the building of even lighter aircraft structures, and thus results in considerable efficiency improvements per passenger kilometer. The treatment of this large, complex, parameter-dependent industrial control problem highlights relevant design issues and provides a relevant case study for modeling and control engineers in many adjacent disciplines and applications. Modeling and Control for a Blended Wing Body Aircraft presents research results in numeric modeling and control design for a large, flexible, civil BWB aircraft in the pre-design stage as developed within the EU FP7 research project ACFA 2020. It is a useful resource for aerospace and control engineers as it shows the complete BWB aircraft modeling and control design process, carried out with the most recent tools and techniques available. presents research results in numeric modeling and control design for a large, flexible, civil BWB aircraft in the pre-design stage as developed within the EU FP7 research project ACFA 2020. It is a useful resource for aerospace and control engineers as it shows the complete BWB aircraft modeling and control design process, carried out with the most recent tools and techniques available. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series offers an opportunity for researchers to present an extended exposition of new work in all aspects of industrial control.

Download or read book Beyond Tube and Wing written by Bruce Larrimer and published by . This book was released on 2020-06-15 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multidisciplinary Methods for Performing Trade Studies on Blended Wing Body Aircraft written by Cory Asher Kays and published by . This book was released on 2013 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multidisciplinary design optimization (MDO) is becoming an essential tool for the design of engineering systems due to the inherent coupling between discipline analyses and the increasing complexity of such systems. An important component of MDO is effective exploration of the design space since this is often a key driver in finding characteristics of systems which perform well. However, many design space exploration techniques scale poorly with the number of design variables and, moreover, a large-dimensional design space can be prohibitive to designer manipulation. This research addresses complexity management in trade-space exploration of multidisciplinary systems, with a focus on the conceptual design of Blended Wing Body (BWB) aircraft. The objectives of this thesis are twofold. The first objective is to create a multidisciplinary tool for the design of BWB aircraft and to demonstrate the performance of the tool on several example trade studies. The second objective is to develop a methodology for reducing the dimension of the design space using designer-chosen partitionings of the design variables describing the system. The first half of this thesis describes the development of the BWB design tool and demonstrates its performance via a comparison to existing methods for the conceptual design of an existing BWB configuration. The BWB design tool is then demonstrated using two example design space trades with respect to planform geometry and cabin bay arrangement. Results show that the BWB design tool provides sufficient fidelity compared to existing BWB analyses, while accurately predicting trends in system performance. The second half of this thesis develops a bi-level methodology for reducing the dimension of the design space for a trade space exploration problem. In this methodology, the designer partitions the design vector into an upper- and lower-level set, wherein the lower-level variables essentially serve as parameters, in which their values are chosen via an optimization with respect to some lower-level objective. This reduces the dimension of the design space, thereby allowing a more manageable space for designer interaction, while subsequently ensuring that the lower-level variables are set to "good" values relative to the lower-level objective. The bi-level method is demonstrated on three test problems, each involving an exploration over BWB planform geometries. Results show that the method constructs surrogate models in which the sampled configurations have a reduction in the system objective by up to 4 % relative to surrogates constructed using a standard exploration. Furthermore, the problems highlight the potential for the framework to reduce the dimension of the design space such that the full space can be visualized.

Download or read book Blended Wing Body Bwb Boundary Layer Ingestion Bli Inlet Configuration and System Studies written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study was conducted to determine the potential reduction in fuel burned for BLI (boundary layer ingestion) inlets on a BWB (blended wing body) airplane employing AFC (active flow control). The BWB is a revolutionary type airplane configuration with engines on the aft upper surface where thick boundary layer offers the greatest opportunity for ram drag reduction. AFC is an emerging technology for boundary layer control. Several BLI inlet configurations were analyzed in the NASA-developed RANS Overflow CFD code. The study determined that, while large reductions in ram drag result from BLI, lower inlet pressure recovery produces engine performance penalties that largely offset this ram drag reduction. AFC could, however, enable a short BLI inlet that allows surface mounting of the engine which, when coupled with a short diffuser, would significantly reduce drag and weight for a potential 10% reduction in fuel burned. Continuing studies are therefore recommended to achieve this reduction in fuel burned considering the use of more modest amounts of BLI coupled with both AFC and PFC (Passive Flow Control) to produce a fail-operational system. Kawai, Ronald T. and Friedman, Douglas M. and Serrano, Leonel Langley Research Center NASA/CR-2006-214534

Download or read book Advanced Aircraft Design written by Egbert Torenbeek and published by John Wiley & Sons. This book was released on 2013-05-28 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although the overall appearance of modern airliners has not changed a lot since the introduction of jetliners in the 1950s, their safety, efficiency and environmental friendliness have improved considerably. Main contributors to this have been gas turbine engine technology, advanced materials, computational aerodynamics, advanced structural analysis and on-board systems. Since aircraft design became a highly multidisciplinary activity, the development of multidisciplinary optimization (MDO) has become a popular new discipline. Despite this, the application of MDO during the conceptual design phase is not yet widespread. Advanced Aircraft Design: Conceptual Design, Analysis and Optimization of Subsonic Civil Airplanes presents a quasi-analytical optimization approach based on a concise set of sizing equations. Objectives are aerodynamic efficiency, mission fuel, empty weight and maximum takeoff weight. Independent design variables studied include design cruise altitude, wing area and span and thrust or power loading. Principal features of integrated concepts such as the blended wing and body and highly non-planar wings are also covered. The quasi-analytical approach enables designers to compare the results of high-fidelity MDO optimization with lower-fidelity methods which need far less computational effort. Another advantage to this approach is that it can provide answers to “what if” questions rapidly and with little computational cost. Key features: Presents a new fundamental vision on conceptual airplane design optimization Provides an overview of advanced technologies for propulsion and reducing aerodynamic drag Offers insight into the derivation of design sensitivity information Emphasizes design based on first principles Considers pros and cons of innovative configurations Reconsiders optimum cruise performance at transonic Mach numbers Advanced Aircraft Design: Conceptual Design, Analysis and Optimization of Subsonic Civil Airplanes advances understanding of the initial optimization of civil airplanes and is a must-have reference for aerospace engineering students, applied researchers, aircraft design engineers and analysts.

Download or read book Aerospace System Analysis and Optimization in Uncertainty written by Loïc Brevault and published by Springer Nature. This book was released on 2020-08-26 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spotlighting the field of Multidisciplinary Design Optimization (MDO), this book illustrates and implements state-of-the-art methodologies within the complex process of aerospace system design under uncertainties. The book provides approaches to integrating a multitude of components and constraints with the ultimate goal of reducing design cycles. Insights on a vast assortment of problems are provided, including discipline modeling, sensitivity analysis, uncertainty propagation, reliability analysis, and global multidisciplinary optimization. The extensive range of topics covered include areas of current open research. This Work is destined to become a fundamental reference for aerospace systems engineers, researchers, as well as for practitioners and engineers working in areas of optimization and uncertainty. Part I is largely comprised of fundamentals. Part II presents methodologies for single discipline problems with a review of existing uncertainty propagation, reliability analysis, and optimization techniques. Part III is dedicated to the uncertainty-based MDO and related issues. Part IV deals with three MDO related issues: the multifidelity, the multi-objective optimization and the mixed continuous/discrete optimization and Part V is devoted to test cases for aerospace vehicle design.

Download or read book The Proceedings of the 2018 Asia Pacific International Symposium on Aerospace Technology APISAT 2018 written by Xinguo Zhang and published by Springer. This book was released on 2019-06-08 with total page 3068 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a compilation of peer-reviewed papers from the 2018 Asia-Pacific International Symposium on Aerospace Technology (APISAT 2018). The symposium is a common endeavour between the four national aerospace societies in China, Australia, Korea and Japan, namely, the Chinese Society of Aeronautics and Astronautics (CSAA), Royal Aeronautical Society Australian Division (RAeS Australian Division), the Korean Society for Aeronautical and Space Sciences (KSAS) and the Japan Society for Aeronautical and Space Sciences (JSASS). APISAT is an annual event initiated in 2009 to provide an opportunity for researchers and engineers from Asia-Pacific countries to discuss current and future advanced topics in aeronautical and space engineering.

Download or read book A Method for Designing Blended Wing body Configurations for Low Wave Drag written by Raymond L. Barger and published by . This book was released on 1992 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Beyond Tube and Wing written by Bruce I. Larrimer and published by NASA. This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "This book details the remarkable efforts to develop a new aircraft configuration known as the Blended Wing-Body (BWB). Responding to a challenge from NASA, McDonnell Douglas Corporation initiated studies in the early 1990s to determine if this new configuration could bring about significant advantages over conventional sweptwing, streamlined tube, and swept-tail designs. Research precipitated the design and construction of two small-scale demonstrators: the X-48B. After McDonnell Douglas' merger with Boeing, the X-48B flew 92 test flights before modification into the X-48C, which in turn flew 30 flights under the auspices of NASA's Environmentally Responsible Aviation Program"--

Download or read book Commercial Aircraft Propulsion and Energy Systems Research written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2016-08-09 with total page 123 pages. Available in PDF, EPUB and Kindle. Book excerpt: The primary human activities that release carbon dioxide (CO2) into the atmosphere are the combustion of fossil fuels (coal, natural gas, and oil) to generate electricity, the provision of energy for transportation, and as a consequence of some industrial processes. Although aviation CO2 emissions only make up approximately 2.0 to 2.5 percent of total global annual CO2 emissions, research to reduce CO2 emissions is urgent because (1) such reductions may be legislated even as commercial air travel grows, (2) because it takes new technology a long time to propagate into and through the aviation fleet, and (3) because of the ongoing impact of global CO2 emissions. Commercial Aircraft Propulsion and Energy Systems Research develops a national research agenda for reducing CO2 emissions from commercial aviation. This report focuses on propulsion and energy technologies for reducing carbon emissions from large, commercial aircraftâ€" single-aisle and twin-aisle aircraft that carry 100 or more passengersâ€"because such aircraft account for more than 90 percent of global emissions from commercial aircraft. Moreover, while smaller aircraft also emit CO2, they make only a minor contribution to global emissions, and many technologies that reduce CO2 emissions for large aircraft also apply to smaller aircraft. As commercial aviation continues to grow in terms of revenue-passenger miles and cargo ton miles, CO2 emissions are expected to increase. To reduce the contribution of aviation to climate change, it is essential to improve the effectiveness of ongoing efforts to reduce emissions and initiate research into new approaches.

Download or read book Longitudinal Aerodynamic Characteristics and Wing Pressure Distributions of a Blended Wing Body Configuration at Low and High Reynolds Numbers written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-15 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Force balance and wing pressure data were obtained on a 0.017-Scale Model of a blended-wing-body configuration (without a simulated propulsion system installation) to validate the capability of computational fluid dynamic codes to predict the performance of such thick sectioned subsonic transport configurations. The tests were conducted in the National Transonic Facility of the Langley Research Center at Reynolds numbers from 3.5 to 25.0 million at Mach numbers from 0.25 to 0.86. Data were obtained in the pitch plane only at angles of attack from -1 to 8 deg at Mach numbers greater than 0.25. A configuration with winglets was tested at a Reynolds number of 25.0 million at Mach numbers from 0.83 to 0.86. Re, Richard J. Langley Research Center WU 23-714-80-VG

Download or read book Evaluation of a Hydrogen Fuel Cell Powered Blended Wing Body Aircraft Concept for Reduced Noise and Emissions written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-20 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the analytical modeling and evaluation of an unconventional commercial transport aircraft concept designed to address aircraft noise and emission issues. A blended-wing-body configuration with advanced technology hydrogen fuel cell electric propulsion is considered. Predicted noise and emission characteristics are compared to a current technology conventional configuration designed for the same mission. The significant technology issues which have to be addressed to make this concept a viable alternative to current aircraft designs are discussed. This concept is one of the "Quiet Green Transport" aircraft concepts studied as part of NASA's Revolutionary Aerospace Systems Concepts (RASC) Program. The RASC Program was initiated to develop revolutionary concepts that address strategic objectives of the NASA Enterprises, such as reducing aircraft noise and emissions, and to identify advanced technology requirements for the concepts.Guynn, Mark D. and Freh, Joshua E. and Olson, Erik D.Glenn Research Center; Langley Research CenterMATHEMATICAL MODELS; EVALUATION; AIRCRAFT DESIGN; AIRCRAFT NOISE; NOISE REDUCTION; AEROSPACE SYSTEMS; BLENDED-WING-BODY CONFIGURATIONS; COMMERCIAL AIRCRAFT; ELECTRIC PROPULSION; FUEL CELLS; NOISE MEASUREMENT

Download or read book Power Based Study of Boundary Layer Ingestion for Aircraft Application written by Peijian Lv and published by Springer Nature. This book was released on 2022-09-14 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents research on Boundary Layer Ingestion (BLI). BLI is an aircraft-engine integration technique that aims at integrating the aircraft and the propulsion system such that the overall aircraft fuel consumption can be reduced. In this research, theoretical analysis suggests that the minimization of total power consumption should be used as a design criterion for aircraft utilizing BLI rather than focusing on the minimization of drag. Numerical simulations are performed, and the simulation results are processed using the PBM to support the theoretical analysis. Furthermore, an experimental study is carried out with a focus on the power conversion processes involved for a propulsor operating in the wake. Stereoscopic PIV is employed in order to visualize the flow and understand the physics. The so-called Power-based Method is used to quantify the power conversion mechanisms. The results prove that the dominant mechanism responsible for the efficiency enhancement is due to the utilization of body wake energy by the wake ingesting propeller. In short, the importance of wake energy flow rate in understanding the BLI phenomenon is highlighted. This book will be useful for researchers in the field of aircraft propulsion, aircraft aerodynamics, and airframe propulsion integration.

Download or read book On Subscale Flight Testing written by Alejandro Sobron and published by Linköping University Electronic Press. This book was released on 2018-11-05 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: Downscaled physical models, also referred to as subscale models, have played an essential role in the investigation of the complex physics of flight until the recent disruption of numerical simulation. Despite the fact that improvements in computational methods are slowly pushing experimental techniques towards a secondary role as verification or calibration tools, real-world testing of physical prototypes still provides an unmatched confidence. Physical models are very effective at revealing issues that are sometimes not correctly identified in the virtual domain, and hence can be a valuable complement to other design tools. But traditional wind-tunnel testing cannot always meet all of the requirements of modern aeronautical research and development. It is nowadays too expensive to use these scarce facilities to explore different design iterations during the initial stages of aircraft development, or to experiment with new and immature technologies. Testing of free-flight subscale models, referred to as Subscale Flight Testing (SFT), could offer an affordable and low-risk alternative for complementing conventional techniques with both qualitative and quantitative information. The miniaturisation of mechatronic systems, the advances in rapid-prototyping techniques and power storage, as well as new manufacturing methods, currently enable the development of sophisticated test objects at scales that were impractical some decades ago. Moreover, the recent boom in the commercial drone industry has driven a quick development of specialised electronics and sensors, which offer nowadays surprising capabilities at competitive prices. These recent technological disruptions have significantly altered the cost-benefit function of SFT and it is necessary to re-evaluate its potential in the contemporary aircraft development context. This thesis aims to increase the comprehension and knowledge of the SFT method in order to define a practical framework for its use in aircraft design; focusing on low-cost, short-time solutions that don’t require more than a small organization and few resources. This objective is approached from a theoretical point of view by means of an analysis of the physical and practical limitations of the scaling laws; and from an empirical point of view by means of field experiments aimed at identifying practical needs for equipment, methods, and tools. A low-cost data acquisition system is developed and tested; a novel method for semi-automated flight testing in small airspaces is proposed; a set of tools for analysis and visualisation of flight data is presented; and it is also demonstrated that it is possible to explore and demonstrate new technology using SFT with a very limited amount of economic and human resources. All these, together with a theoretical review and contextualisation, contribute to increasing the comprehension and knowledge of the SFT method in general, and its potential applications in aircraft conceptual design in particular.

Download or read book Green Aviation written by Ramesh Agarwal and published by John Wiley & Sons. This book was released on 2016-10-17 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Green Aviation is the first authoritative overview of both engineering and operational measures to mitigate the environmental impact of aviation. It addresses the current status of measures to reduce the environmental impact of air travel. The chapters cover such items as: Engineering and technology-related subjects (aerodynamics, engines, fuels, structures, etc.), Operations (air traffic management and infrastructure) Policy and regulatory aspects regarding atmospheric and noise pollution. With contributions from leading experts, this volume is intended to be a valuable addition, and useful resource, for aerospace manufacturers and suppliers, governmental and industrial aerospace research establishments, airline and aviation industries, university engineering and science departments, and industry analysts, consultants, and researchers.