Shear flow aerodynamics - Lifting surface theory

A lifting-surface theory is presented for a cascade in subsonic shear flow by applying Fourier integral methods to the expressions of the perturbed flow field. The pressure distribution on the blade surface is determined by means of the socalled singularity method. Some numerical examples are presented and discussed in comparison with the results according to the lifting-line theory.A significant difference is found in the effect of compressibility between a shear flow and a uniform flow. In shear flows with the maximum Mach number close to one, no such great local lift force is found near the sonic station as would be predicted by the linearized subsonic uniform flow theory. The correlation between the local lift and the local effective angle of attack at high Mach number span-stations shows a great deviation from that according to the uniform flow theory.

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Continuity of lifting surface theory in subsonic and supersonic flow

AIAA Journal ◽

10.2514/3.14049 ◽

1998 ◽

Vol 36 ◽

pp. 1788-1791

Author(s):

Tetsuhiko Ueda

Keyword(s):

Supersonic Flow ◽

Surface Theory ◽

Lifting Surface

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A lifting surface theory for the sound generated by the interaction of velocity disturbances with a leaned vane stator

10.2514/6.1981-91 ◽

1981 ◽

Cited By ~ 1

Author(s):

J. SCHULTEN

Keyword(s):

Surface Theory ◽

Lifting Surface

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Unsteady Lifting Surface Theory for a Rotating Cascade of Swept Blades

Volume 1: Turbomachinery ◽

10.1115/89-gt-306 ◽

1989 ◽

Cited By ~ 2

Author(s):

Hidekazu Kodama ◽

Masanobu Namba

Keyword(s):

Three Dimensional ◽

Acoustic Power ◽

Aerodynamic Characteristics ◽

Blade Loading ◽

Surface Theory ◽

Numerical Examples ◽

Lifting Surface ◽

Blade Flutter ◽

Annular Cascade ◽

Remarkable Reduction

A lifting surface theory is developed to predict the unsteady three-dimensional aerodynamic characteristics for a rotating subsonic annular cascade of swept blades. A discrete element method is used to solve the integral equation for the unsteady blade loading. Numerical examples are presented to demonstrate effects of the sweep on the blade flutter and on the acoustic field generated by interaction of rotating blades with a convected sinusoidal gust. It is found that increasing the sweep results in decrease of the aerodynamic work on vibrating blades and also remarkable reduction of the modal acoustic power of lower radial orders for both forward and backward sweeps.

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Lifting-Surface Theory for an Oscillating T-Tail

AIAA Journal ◽

10.2514/3.49149 ◽

1974 ◽

Vol 12 (1) ◽

pp. 28-37 ◽

Cited By ~ 3

Author(s):

KOJI ISOGAI

Keyword(s):

Surface Theory ◽

Lifting Surface

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New directions in lifting surface theory

10.2514/6.1964-1 ◽

1964 ◽

Author(s):

H. ASHLEY ◽

M. LANDAHL

Keyword(s):

Surface Theory ◽

Lifting Surface ◽

New Directions

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Derivation by a Transform Method of Integral Equations of Unsteady Lifting Surface Theory in Subsonic and Supersonic Flow

Aeronautical Quarterly ◽

10.1017/s0001925900008714 ◽

1979 ◽

Vol 30 (4) ◽

pp. 529-543

Author(s):

Shigenori Ando ◽

Akio Ichikawa

Keyword(s):

Fourier Transforms ◽

Integral Transforms ◽

Physical Models ◽

Streamwise Direction ◽

Fourier Inversion ◽

Transform Method ◽

Inviscid Flows ◽

Surface Theory ◽

Method Of Integral Equations ◽

Lifting Surface

SummaryApplications of “integral transforms of in-plane coordinate variables” in order to formulate unsteady planar lifting surface theories are demonstrated for both sub- and supersonic inviscid flows. It is concise and pithy. Fourier transforms are exclusively used, except for only Laplace transform in the supersonic streamwise direction. It is found that the streamwise Fourier inversion in the subsonic case requires some caution. Concepts based on the theory of distributions seem to be essential, in order to solve the convergence difficulties of integrals. Apart from this caution, the method of integral transforms of in-plane coordinate variables makes it be pure-mathematical to formulate the lifting surface problems, and makes aerodynamicist’s experiences and physical models such as vortices or doublets be useless.

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