Unsteady Transonic Flow


Book Description

This classic monograph on unsteady transonic flow — the flow of air encountered at speeds at or near the speed of sound — is of continuing interest to students and professionals in aerodynamics, fluid dynamics, and other areas of applied mathematics. After a brief Introduction, Swedish physicist Mårten T. Landahl presents a chapter in which the two-dimensional solution is derived, succeeded by a discussion of its relation to the subsonic and supersonic solutions. Three chapters on low aspect ratio configurations follow, covering triangular wings and similar planforms with curved leading edges, rectangular wings, and cropped delta wings, and low aspect ratio wing-body combinations. The treatment concludes with a consideration of the experimental determination of air forces on oscillating wings at transonic speeds.




Unsteady Transonic Aerodynamics


Book Description

This volume complements Transonic aerodynamics (v.81 in the series) which is concerned with steady flow. This is the only book to address the subject of unsteady transonic aerodynamics, a field much different from steady aerodynamics. The most pronounced difference is the complex shock wave motions







Transonic Aerodynamics


Book Description

This volume offers exciting results, perspectives, and case studies for the treatment of problems arising in transonic aerodynamics. New advances including triple deck theory, analysis of stagnation at the nose of a body, transonic choked flow, and the transonic area rule are presented. Interest in analyzing the transonic range of flight, its stability properties, and especially the question of designing reduced drag (shockless or weak shock) airfoils keeps growing. Present day commercial aircraft cruise in the transonic range. Mechanical and aeronautical engineers interested in compressible fluid flows, design of optimal wings, and an understanding of transonic flow held about wings and airfoils will find the book invaluable. This book is understandable to those with a knowledge of continuum mechanics (fluids) and asymptotic methods. It is appropriate for graduate courses in aerodynamics and mathematical methods.




Modern Aerodynamic Methods for Direct and Inverse Applications


Book Description

A powerful new monograph from an aerodynamicist reviewing modern conventional aerodynamic approaches, this volume covers aspects of subsonic, transonic and supersonic flow, inverse problems, shear flow analysis, jet engine power addition, engine and airframe integration, and other areas, providing readers with the tools needed to evaluate their own ideas and to implement the newer methods suggested in this book. This new book, by a prolific fluid-dynamicist and mathematician who has published more than twenty research monographs, represents not just another contribution to aerodynamics, but a book that raises serious questions about traditionally accepted approaches and formulations, providing new methods that solve longstanding problems of importance to the industry. While both conventional and newer ideas are discussed, the presentations are readable and geared to advanced undergraduates with exposure to elementary differential equations and introductory aerodynamics principles. Readers are introduced to fundamental algorithms (with Fortran source code) for basic applications, such as subsonic lifting airfoils, transonic supercritical flows utilizing mixed differencing, models for inviscid shear flow aerodynamics, and so on. These are models they can extend to include newer effects developed in the second half of the book. Many of the newer methods have appeared over the years in various journals and are now presented with deeper perspective and integration. This book helps readers approach the literature more critically. Rather than simply understanding an approach, for instance, the powerful "type differencing" behind transonic analysis, or the rationale behind "conservative" formulations, or the use of Euler equation methods for shear flow analysis when they are unnecessary, the author guides and motivates the user to ask why and why not and what if. And often, more powerful methods can be developed using no more than simple mathematical manipulations. For example, Cauchy-Riemann conditions, which are powerful tools in subsonic airfoil theory, can be readily extended to handle compressible flows with shocks, rotational flows, and even three-dimensional wing flowfields, in a variety of applications, to produce powerful formulations that address very difficult problems. This breakthrough volume is certainly a "must have" on every engineer's bookshelf.













Principles of Helicopter Aerodynamics


Book Description

Helicopters are highly capable and useful rotating-wing aircraft with roles that encompass a variety of civilian and military applications. Their usefulness lies in their unique ability to take off and land vertically, to hover stationary relative to the ground, and to fly forward, backward, or sideways. These unique flying qualities, however, come at a high cost including complex aerodynamic problems, significant vibrations, high levels of noise, and relatively large power requirements compared to fixed-wing aircraft. This book, written by an internationally recognized expert, provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft. Every chapter is extensively illustrated and concludes with a bibliography and homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thorough and up-to-date text on rotating-wing aerodynamics.