A Survey of Challenges in Aerodynamic Exhaust Nozzle Technology for Aerospace Propulsion Applications


Book Description

The current paper discusses aerodynamic exhaust nozzle technology challenges for aircraft and space propulsion systems. Technology advances in computational and experimental methods have led to more accurate design and analysis tools, but many major challenges continue to exist in nozzle performance, jet noise and weight reduction. New generations of aircraft and space vehicle concepts dictate that exhaust nozzles have optimum performance, low weight and acceptable noise signatures. Numerous innovative nozzle concepts have been proposed for advanced subsonic, supersonic and hypersonic vehicle configurations such as ejector, mixer-ejector, plug, single expansion ramp, altitude compensating, lobed and chevron nozzles. This paper will discuss the technology barriers that exist for exhaust nozzles as well as current research efforts in place to address the barriers. Shyne, Rickey J. Glenn Research Center NASA/TM-2002-211977, NAS 1.15:211977, E-13646













Aircraft Propulsion


Book Description

New edition of the successful textbook updated to include new material on UAVs, design guidelines in aircraft engine component systems and additional end of chapter problems Aircraft Propulsion, Second Edition follows the successful first edition textbook with comprehensive treatment of the subjects in airbreathing propulsion, from the basic principles to more advanced treatments in engine components and system integration. This new edition has been extensively updated to include a number of new and important topics. A chapter is now included on General Aviation and Uninhabited Aerial Vehicle (UAV) Propulsion Systems that includes a discussion on electric and hybrid propulsion. Propeller theory is added to the presentation of turboprop engines. A new section in cycle analysis treats Ultra-High Bypass (UHB) and Geared Turbofan engines. New material on drop-in biofuels and design for sustainability is added to refl ect the FAA’s 2025 Vision. In addition, the design guidelines in aircraft engine components are expanded to make the book user friendly for engine designers. Extensive review material and derivations are included to help the reader navigate through the subject with ease. Key features: General Aviation and UAV Propulsion Systems are presented in a new chapter Discusses Ultra-High Bypass and Geared Turbofan engines Presents alternative drop-in jet fuels Expands on engine components' design guidelines The end-of-chapter problem sets have been increased by nearly 50% and solutions are available on a companion website Presents a new section on engine performance testing and instrumentation Includes a new 10-Minute Quiz appendix (with 45 quizzes) that can be used as a continuous assessment and improvement tool in teaching/learning propulsion principles and concepts Includes a new appendix on Rules of Thumb and Trends in aircraft propulsion Aircraft Propulsion, Second Edition is a must-have textbook for graduate and undergraduate students, and is also an excellent source of information for researchers and practitioners in the aerospace and power industry.




Distributed Propulsion Technology


Book Description

Distributed propulsion technology is one of the revolutionary candidates for future aircraft propulsion. In this book, which serves as the very first reference book on distributed propulsion technology, the potential role of distributed propulsion technology in future aviation is investigated. Following a historical journey that revisits distributed propulsion technology in unmanned air vehicles, commercial aircrafts, and military aircrafts, features of this specific technology are highlighted in synergy with an electric aircraft concept and a first-of-its-kind comparison between commercial and military aircrafts employing distributed propulsion arrangements. In light of propulsionairframe integration and complementary technologies, such as boundary layer ingestion, thrust vectoring and circulation control, transpired opportunities and challenges are addressed in addition to a number of identified research directions proposed for future aircrafts. Moreover, a diverse set of distributed propulsion arrangements are considered. These include: small engines, gas-driven multi-fan architectures, turboelectric systems featuring superconductive and non-superconducting electrical machine technology, and electromagnetic fans. This book features contributions by the National Aeronautics and Space Administration (NASA) and the United States Air Force (USAF), and includes the first proposed official definition for distributed propulsion technology in subsonic fixed wing aircrafts.