Author: Goetz H. Klopfer Publisher: ISBN: Category : Languages : en Pages : 87
Book Description
The problem of computing the steady inviscid supersonic flows about thin wings having sharp subsonic leading edges and leading-edge separation is solved in this paper. Both wings alone or wings in the presence of the body are considered. To obtain an efficient procedure the steady Euler equations are used as the basic governing equations as opposed to the more complicated Navier-Stokes equation. The viscous effects, important near the sharp leading edges, are simulated by a Kutta condition applied at the leading edges of the wings. The rest of the flow field is essentially controlled by the inviscid equations. The equations, written in conservation form in generalized curvilinear coordinates, are approximated by MacCormack's second-order accurate predictor-corrector algorithm. The flow tangency conditions at the body surface are satisfied by Abbett's scheme and the outer bow-shock position by the Rankine-Hugoniot jump relations. Internal shock waves or tangentially discontinuities are captured. The slip surface emanating from the leading edge of the sharp wing excited nonlinear instabilities in the MacCormack's scheme, which were stabilized by special flow dependent fourth-order damping terms.
Author: Josef Rom Publisher: Springer Science & Business Media ISBN: 1461228247 Category : Science Languages : en Pages : 408
Book Description
The aerodynamics of aircraft at high angles of attack is a subject which is being pursued diligently, because the modern agile fighter aircraft and many of the current generation of missiles must perform well at very high incidence, near and beyond stall. However, a comprehensive presentation of the methods and results applicable to the studies of the complex aerodynamics at high angle of attack has not been covered in monographs or textbooks. This book is not the usual textbook in that it goes beyond just presenting the basic theoretical and experimental know-how, since it contains reference material to practical calculation methods and technical and experimental results which can be useful to the practicing aerospace engineers and scientists. It can certainly be used as a text and reference book for graduate courses on subjects related to high angles of attack aerodynamics and for topics related to three-dimensional separation in viscous flow courses. In addition, the book is addressed to the aerodynamicist interested in a comprehensive reference to methods of analysis and computations of high angle of attack flow phenomena and is written for the aerospace scientist and engineer who is familiar with the basic concepts of viscous and inviscid flows and with computational methods used in fluid dynamics.
Author: Jack N. Nielsen Publisher: ISBN: Category : Aerodynamics, Supersonic Languages : en Pages : 63
Book Description
An exact theoretical method is developed that permits the determination of the pressure field of a wing-body combination having a circular body and wings with supersonic leading and trailing edges. Detailed calculations are performed for the case of a rectangular wing or all-movable control surface on a body at zero angle of attack. Design charts are presented showing the effect of interference on the lift and center-of-pressure position of the wings. The physical basis of the interference is discussed.
Author: Richard T. Whitcomb Publisher: ISBN: Category : Airplanes Languages : en Pages : 20
Book Description
Summary: As an extension of the transonic area rule, a concept for interrelating the wave drags of wing-body combinations at moderate supersonic speeds with axial developments of cross-sectional area has been derived. The wave drag of a combination at a given supersonic speed is related to a number of developments of cross-sectional areas as intersected by Mach planes. On the basis of this concept and other design procedures, a structurally feasible, swept-wing--indented-body combination has been designed to have relatively high maximum lift-drag ratios over a range of transonic and moderate supersonic Mach numbers. The wing of the combination has been designed to have reduced drag associated with lift and, when used with an indented body, to have low zero-lift wave drag. Experimental results have been obtained for this configuration at Mach numbers from 0.80 to 2.01. Maximum lift-drag ratios of approximately 14 and 9 were measured at Mach numbers of 1.15 and 1.41, respectively.
Author: Charlie M. Jackson Publisher: ISBN: Category : Aerodynamics, Supersonic Languages : en Pages : 44
Book Description
This report describes a theoretical method for estimating the aerodynamic loading on a wing-body configuration. In order to provide a basis for evaluation of the method, experimental measurements of surface pressures, forces, and moments were made on a series of basic wing-body configurations over a Mach number range from 2.5 to 4.5. Comparison of the theoretical estimates with these experimental data generally indicated good agreement for the entire range of configurations and test conditions.
Author: A. J. Eggers (Jr.) Publisher: ISBN: Category : Aerodynamics Languages : en Pages : 42
Book Description
Summary: The problem of designing an aircraft which will develop high lift-drag ratios in flight at high supersonic speeds is attacked using the elementary principle that the components of the aircraft should be individually and collectively arranged to impart the maximum downward and the minimum forward momentum to the surrounding air. This principle in conjunction with other practical considerations of hypersonic flight leads to the study of configurations for which the body is situated entirely below the wing; that is, flat-top wing-body combinations. Theory indicates that sensibly complete aircraft of this type can be designed to develop lift-drag ratios well in excess of 6.
Author: Goetz H. Klopfer
Author: Josef Rom
Author: Ross B. Robinson
Author: Ralph L. Carmichael
Author: Jack N. Nielsen
Author: Richard T. Whitcomb
Author: R. C. MEYER
Author: Raymond C. Savin
Author: Charlie M. Jackson
Author: A. J. Eggers (Jr.)