121 research outputs found
Effects of jets, wakes, and vortices on lifting surfaces
The interaction of jets, wakes, and vortices on lifting bodies represents a broad spectrum of aerodynamic flow phenomena. A literature survey is presented of 79 research activities in related aerodynamic situations
Computer program calculates wing aerodynamic characteristics for fixed wings with dihedral and variable-sweep wings at subsonic speeds
Vortex lattice is used to describe the lifting surface of an arbitrary wing planform in steady potential subsonic compressible flow in computer program which calculates wing aerodynamic characteristics. Estimates of flow field characteristics in the vicinity of a lifting wing can also be programmed
Vortex-lattice FORTRAN program for estimating subsonic aerodynamic characteristics of complex planforms
Computer program for estimating subsonic aerodynamic characteristics of various aerodynamic configurations is presented. Program represents lifting planforms with vortex-lattice. Specific aerodynamic characteristics to be determined are described. Examples and typical running times of various types of configurations are provided
Pressure distribution on a vectored-thrust V/STOL fighter in the transition-speed range
A wind-tunnel investigation has been conducted in the Langley V/STOL tunnel with a vectored-thrust V/STOL fighter configuration to obtain detailed pressure measurements on the body and on the wing in the transition-speed range. The vectored-thrust jet exhaust induced a region of negative pressure coefficients on the lower surface of the wing and on the bottom of the fuselage. The location of the jet exhaust relative to the wing was a major factor in determining the extent of the region of negative pressure coefficients
An experimental investigation of a highly underexpanded sonic jet ejecting from a flat plate into a subsonic crossflow
The induced static pressures due to a highly underexpanded sonic jet ejecting normally from a flat plate into a subsonic crosswind have been investigated. These pressure data have been recorded on the flat plate for a range of nominal jet-to-free-stream dynamic-pressure ratios from 0 to 1000 at free-stream Mach numbers of 0.1, 0.2, 0.4, and 0.6. The static pressure data measured on the flat plate are presented and correlated based upon the Riemann shock geometry in the jet plume. This data correlation improves with increasing free-stream Mach number
Separated flow
A brief overview of flow separation phenomena is provided. Langley has many active research programs in flow separation related areas. Three cases are presented which describe specific examples of flow separation research. In each example, a description of the fundamental fluid physics and the complexity of the flow field is presented along with a method of either reducing or controlling the extent of separation. The following examples are discussed: flow over a smooth surface with an adverse pressure gradient; flow over a surface with a geometric discontinuity; and flow with shock-boundary layer interactions. These results will show that improvements are being made in the understanding of flow separation and its control
- …