Effect of Unsymmetrical Nose-bluntness of the Pressure Distribution Over a 10° Cone at Mach-14

Effect of Unsymmetrical Nose-bluntness of the Pressure Distribution Over a 10° Cone at Mach-14 PDF Author: Otto Walchner
Publisher:
ISBN:
Category : Aerodynamic load
Languages : en
Pages : 35

Get Book Here

Book Description

Effect of Unsymmetrical Nose-bluntness of the Pressure Distribution Over a 10° Cone at Mach-14

Effect of Unsymmetrical Nose-bluntness of the Pressure Distribution Over a 10° Cone at Mach-14 PDF Author: Otto Walchner
Publisher:
ISBN:
Category : Aerodynamic load
Languages : en
Pages : 35

Get Book Here

Book Description


Effect of Unsymmetrical Nose-Bluntness of the Pressure Distribution Over a 10 Degree Cone at Mach-14

Effect of Unsymmetrical Nose-Bluntness of the Pressure Distribution Over a 10 Degree Cone at Mach-14 PDF Author: Otto Walchner
Publisher:
ISBN:
Category :
Languages : en
Pages : 46

Get Book Here

Book Description
The pressure distribution over a 10 deg cone was measured in ARL's 20-inch hypersonic wind tunnel at Mach-14 and for various angles of attack and sideslip. The effect of different unsymmetrically blunted noses, with small bluntness ratios, on the pressure distribution is investigated. Test results relate any small unsymmetrical nose bluntness to the rotational symmetry of the flow over a body of revolution at high Mach numbers. The reported test complement, AD-711 921. (Author).

Effect of Unsymmetrical Nose-bluntness on the Stability Derivatives of a 10 Degree Cone at Mach-14

Effect of Unsymmetrical Nose-bluntness on the Stability Derivatives of a 10 Degree Cone at Mach-14 PDF Author: Otto Walchner
Publisher:
ISBN:
Category :
Languages : en
Pages : 27

Get Book Here

Book Description
In the analysis of the free flight motion of bodies of revolution, the tricyclic theory assumes that a small configurational asymmetry does not violate the rotational symmetry of the stability derivatives in pitch and yaw but does produce a non-zero trim angle. Tests at Mach 14 show that a small unsymmetric nose bluntness destroys the rotational symmetry of the stability derivatives of a slender cone at hypersonic Mach numbers and therefore severely violates the assumptions of the tricyclic theory. Restoring and damping derivatives in pitch and yaw are reported for a 10 deg cone with symmetric and unsymmetrically blunted noses. The effect of non-equal stability derivatives on the motion are shown for a simplified case. (Author).

Asymmetric Nose Bluntness Effect on the Aerodynamics of a Slender Cone at Mach-14

Asymmetric Nose Bluntness Effect on the Aerodynamics of a Slender Cone at Mach-14 PDF Author: Otto Walchner
Publisher:
ISBN:
Category :
Languages : en
Pages : 32

Get Book Here

Book Description
Experiments were performed in ARL's 20-inch hypersonic wind tunnel on a 10 degree half-angle circular cone model whose pointed tip was removed by one or more planar slanted cuts. The projected frontal nose area was 1/2 percent of the base area. The configurational asymmetry of this moderate bluntness destroys the rotational symmetry of the shock wave over the entire model. In turn, the rotational symmetry of the surface pressure distribution is also lost. Depending on the nose configuration, asymmetric sideloads were observed at axial flow conditions which may or may not cause the vehicle to trim in free flight. Nose asymmetry combined with mass asymmetry, therefore, may produce a rolling moment even at zero trim. The stability derivatives are not identical in pitch and yaw, as would be expected for a body of revolution, and vary differently as functions of the angle of attack and angle of sideslip. (Modified author abstract).

Asymmetric Nose Bluntness Effects on the Aerodynamics of a Slender Cone at Mach-14

Asymmetric Nose Bluntness Effects on the Aerodynamics of a Slender Cone at Mach-14 PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

Get Book Here

Book Description
Experiments were performed in ARL's 20-inch hypersonic wind tunnel on a 10 degree half-angle circular cone model whose pointed tip was removed by one or more planar slanted cuts. The projected frontal nose area was 1/2 percent of the base area. The configurational asymmetry of this moderate bluntness destroys the rotational symmetry of the shock wave over the entire model. In turn, the rotational symmetry of the surface pressure distribution is also lost. Depending on the nose configuration, asymmetric sideloads were observed at axial flow conditions which may or may not cause the vehicle to trim in free flight. Nose asymmetry combined with mass asymmetry, therefore, may produce a rolling moment even at zero trim. The stability derivatives are not identical in pitch and yaw, as would be expected for a body of revolution, and vary differently as functions of the angle of attack and angle of sideslip. (Modified author abstract).

Research on Hypersonic Stability Problems

Research on Hypersonic Stability Problems PDF Author: O. Walchner
Publisher:
ISBN:
Category : Aerodynamics, Hypersonic
Languages : en
Pages : 20

Get Book Here

Book Description
This final report summarizes the in-house research work on hypersonic stability problems, applicable to reentry dynamics. During the period 1963 to 1974 research contributions were made in the following areas: (1) Static and dynamic stability in pitch; (2) hypersonic roll damping; (3) asymmetric nose effects; (4) non linear aerodynamics; (5) stability coefficients in nonplanar motions. This in-house research effort was terminated as of 1 July 1974.

Pressure Distribution on a 5.6° Blunt Cone at Mach 14

Pressure Distribution on a 5.6° Blunt Cone at Mach 14 PDF Author: Eric G. Friberg
Publisher:
ISBN:
Category : Aerodynamic load
Languages : en
Pages : 64

Get Book Here

Book Description


Pressure Distribution on a 5.6 Degree Blunt Cone at Mach 14

Pressure Distribution on a 5.6 Degree Blunt Cone at Mach 14 PDF Author: Eric G. Friberg
Publisher:
ISBN:
Category :
Languages : en
Pages : 77

Get Book Here

Book Description
The pressure distribution around a 5.6 deg half-angle cone with various nose bluntness ratios was measured in a 20-inch hypersonic wind tunnel at Mach 14 and Re 160,000. An empirical expression for the circumferential pressure distribution at small angles of attack is derived which allows the integration of normal pressure components in closed form. Correlation of the pressure data along the most windward ray at angle of attack by means of the tangent cone concept is shown to be possible if viscous interaction is negligible. For the most windward ray of the 5.6 deg cone this is the case for positive angles of attack only. At negative angles of attack the viscous effects dominate and prevent the correlation. The pitching moment derivative was calculated for several noses on the basis of the measured pressure distributions at angles of attack. (Author).

Scientific and Technical Aerospace Reports

Scientific and Technical Aerospace Reports PDF Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1282

Get Book Here

Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

The Effect of Severe Nose Bluntness on the Stability of Slender Cones in Hypersonic Flow

The Effect of Severe Nose Bluntness on the Stability of Slender Cones in Hypersonic Flow PDF Author: Brian Quinn
Publisher:
ISBN:
Category :
Languages : en
Pages : 33

Get Book Here

Book Description
The flow around a blunted slender cone performing pitching oscillations is theoretically analyzed by means of Chernyi's blast-wave piston analogy. Stationary and transient shock shapes and pressure distributions are presented in power series form. Within the region of applicability, the stationary pressure agrees well with Chernyi's numerical integration. Normal force and pitching moment coefficient derivatives are presented and the results are plotted for a 10 degree cone. The theoretical static and dynamic stability derivatives agree satisfactorily with recent experiments in a Mach 14 wind tunnel. It is concluded that the experimentally observed reduction in static and dynamic stability due to increased nose bluntness may be attributed to blast wave effects. (Author).