Aerodynamics Of A Lifting System In Extreme Ground Effect

This book is dedicated to the memory of a distinguished Russian engineer, Rostislav E. Alexeyev, who was the first in the world to develop the largest ground effect machine - Ekranoplan. One of Alexeyev's design concepts with the aerodynamic configuration of a jlying wing can be seen on the front page. The book presents a description of a mathematical model of flow past a lifting system, performing steady and unsteady motions in close proximity to the underlying solid surface (ground). This case is interesting for practical purposes because both the aerodynamic and the economic efficiency of the system near the ground are most pronounced. Use of the method of matched asymptotic expansions enables closed form solutions for the aerodynamic characteristics of the wings-in-ground effect. These can be used for design, identification, and processing of experimental data in the course of developing ground effect vehicles. The term extreme ground effect, widely used through out the book, is associated with very small relative ground clearances of the order of 10% or less. The theory of a lifting surface, moving in immediate proximity to the ground, represents one of the few limiting cases that can be treated analytically. The author would like to acknowledge that this work has been influenced by the ideas of Professor Sheila E. Widnall, who was the first to apply the matched asymptotics techniques to treat lifting flows with the ground effect. Saint Petersburg, Russia February 2000 Kirill V. Rozhdestvensky Contents 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

This book presents a detailed look at high-lift aerodynamics, which deals with the aerodynamic behavior of lift augmentation means from various approaches. After an introductory chapter, the book discusses the physical limits of lift generation, giving the lift generation potential. It then explains what is needed for an aircraft to fly safely by analyzing the high-lift-related requirements for certifying an aircraft. Aircraft needs are also analyzed to improve performance during takeoff, approach, and landing. The book discusses in detail the applied means to increase the lift coefficient by either passive and active high-lift systems. It includes slotless and slotted high-lift flaps, active and passive vortex generating devices, boundary and circulation control, and powered lift. Describing methods that are used to evaluate and design high-lift systems in an aerodynamic sense, the book briefly covers numerical as well as experimental simulation methods. It also includes a chapter on the aerodynamic design of high-lift systems. FEATURES Provides an understanding of the physics of flight during takeoff and landing from aerodynamics to flight performance and from simulation to design Discusses the physical limits of lift generation, giving the lift generation potential Concentrates on the specifics of high-lift aerodynamics to provide a first insight Analyzes aircraft needs to improve performance during takeoff, approach, and landing Focuses on civil transport aircraft applications but also includes the associated physics that apply to all aircraft This book is intended for graduate students in aerospace programs studying advanced aerodynamics and aircraft design. It also serves as a professional reference for practicing aerospace and mechanical engineers who are working on aircraft design issues related to takeoff and landing.

A constant-angle-of-attack-approach technique was used to measure ground effect on several low -aspect-ratio aircraft. The flight results were compared with results from constant -altitude flybys, wind-tunnel studies, and theoretical prediction data. It was found that the constantangle-of-attack technique provided data that were consistent with data obtained from constant-altitude flybys and required fewer runs to obtain the same amount of data. The test results from an F5D-1 airplane modified with an ogee wing, a prototype F5D-1 airplane, two XB-70 airplanes, and an F-104A airplane indicate that theory and wind-tunnel results adequately predict the trends caused by ground effect as a function of height and aspect ratio. However, the magnitude of these predictions did not always agree with the flightmeasured results. In addition, there was consistent evidence that the aircraft encountered ground effect at a height above one wing span.

Maritime Technology and Engineering 3 is a collection of papers presented at the 3rd International Conference on Maritime Technology and Engineering (MARTECH 2016, Lisbon, Portugal, 4-6 July 2016). The MARTECH Conferences series evolved from biannual national conferences in Portugal, thus reflecting the internationalization of the maritime sector. The keynote lectures and the papers, making up nearly 150 contributions, came from an international group of authors focused on different subjects in a variety of fields: Maritime Transportation, Energy Efficiency, Ships in Ports, Ship Hydrodynamics, Ship Structures, Ship Design, Ship Machinery, Shipyard Technology, afety & Reliability, Fisheries, Oil & Gas, Marine Environment, Renewable Energy and Coastal Structures. This book will appeal to academics, engineers and professionals interested or involved in these fields.

In the last half-century, high-speed water transportation has developed rapidly. Novel high-performance marine vehicles, such as the air cushion vehicle (ACV), surface effect ship (SES), high-speed monohull craft (MHC), catamaran (CAT), hydrofoil craft (HYC), wave-piercing craft (WPC) and small water area twin hull craft (SWATH) have all developed as concepts, achieving varying degrees of commercial and military success. Prototype ACV and SES have achieved speeds of 100 knots in at calm con- tions; however, the normal cruising speed for commercial operations has remained around 35–50 knots. This is partly due to increased drag in an average coastal s- way where such craft operate services and partly due to limitations of the propulsion systems for such craft. Water jets and water propellers face limitations due to c- itation at high speed, for example. SWATH are designed for reduced motions in a seaway, but the hull form is not a low drag form suitable for high-speed operation. So that seems to lead to a problem – maintain water contact and either water propulsion systems run out of power or craft motions and speed loss are a problem in higher seastates. The only way to higher speed would appear to be to disconnect completely from the water surface. You, the reader, might respond with a question about racing hydroplanes, which manage speeds of above 200 kph. Yes, true, but the power-to-weight ratio is extremely high on such racing machines and not economic if translated into a useful commercial vessel.

This book gathers the latest advances, innovations and applications in the field of robotics and mechatronics, as presented by leading international researchers and engineers at the 6th IFToMM International Symposium on Robotics and Mechatronics (ISRM), held in Taipei, Taiwan, on October 28–30, 2019. It covers highly diverse topics, including mechanism synthesis, analysis, and design, kinematics and dynamics of multibody systems, modelling and simulation, sensors and actuators, novel robotic systems, industrial- and service-related robotics and mechatronics, medical robotics, and historical developments in robotics and mechatronics. The contributions, which were selected through a rigorous international peer-review process, share exciting ideas that spur novel research directions and foster new, multidisciplinary collaborations.

Aerodynamics of Road Vehicles details the aerodynamics of passenger cars, commercial vehicles, sports cars, and race cars; their external flow field; as well as their internal flow field. The book, after giving an introduction to automobile aerodynamics and some fundamentals of fluid mechanics, covers topics such as the performance and aerodynamics of different kinds of vehicles, as well as test techniques for their aerodynamics. The book also covers other concepts related to automobiles such as cooling systems and ventilations for vehicles. The text is recommended for mechanical engineers and phycisists in the automobile industry who would like to understand more about aerodynamics of motor vehicles and its importance on the field of road safety and automobile production.