Nonequilibrium excitation of internal molecular degrees of freedom in the shock layer during hypersonic flight

Shock Waves ◽  
1992 ◽  
Vol 2 (3) ◽  
pp. 139-146 ◽  
Author(s):  
V. M. Doroshenko ◽  
N. N. Koudriavtsev ◽  
V. V. Smetanin
Keyword(s):  
Shock Layer ◽  
Degrees Of Freedom ◽  
Hypersonic Flight ◽  
Nonequilibrium Excitation

Damage-Mitigating Predictive Control of Airfoil Flutter for a General Hypersonic Flight Vehicle

2019 ◽  
Vol 141 (5) ◽  
Author(s):  
Xiaohui Zhang ◽  
Yuhui Wang ◽  
Xingkai Feng ◽  
Siyuan Hou
Keyword(s):  
Predictive Control ◽  
Degrees Of Freedom ◽  
Unsteady Aerodynamics ◽  
Flight Vehicle ◽  
Hypersonic Flight Vehicle ◽  
Hypersonic Flight ◽  
Online Simulation ◽  
Nonlinear Predictive Control ◽  
Predictive Controller ◽  
Damage Accumulation Model

Abstract This paper aims to investigate the airfoil flutter damage-mitigating problem in hypersonic flow. A new adaptive robust nonlinear predictive control law is designed in this paper to mitigate the damage during airfoil flutter of a generic hypersonic flight vehicle. A three-degrees-of-freedom airfoil dynamic motion model is established, in which the third piston theory is employed to derive the unsteady aerodynamics. Then, the complicated responses of the hypersonic airfoil flutter model are analyzed. In order to mitigate the damage of the airfoil, a predictive controller is designed by introducing an adaptive predictive period, and asymptotical stability analysis of the robust nonlinear predictive controller is performed. Subsequently, based on the nonlinear aerodynamics of the airfoil and damage accumulation model, the damage of the airfoil is observed online. Simulation results illustrate the effectiveness of the proposed method.

Blunt body flow with account for nonequilibrium excitation of the vibrational degrees of freedom

1972 ◽  
Vol 5 (1) ◽  
pp. 33-40
Author(s):  
A. L. Kosorukov
Keyword(s):  
Degrees Of Freedom ◽  
Blunt Body ◽  
Nonequilibrium Excitation

scholarly journals Radiative Heat Transfer from a Nonequilibrium Shock Layer Generated around a Hypersonic Flight Model.

1994 ◽  
Vol 42 (487) ◽  
pp. 503-509
Author(s):  
Kimiya KOMURASAKI ◽  
Jiro KASAHARA ◽  
Shujiro YANO ◽  
Toshi FUJIWARA
Keyword(s):  
Heat Transfer ◽  
Radiative Heat Transfer ◽  
Shock Layer ◽  
Radiative Heat ◽  
Hypersonic Flight ◽  
Flight Model

Dynamic damage analysis of airfoil flutter for a generic hypersonic flight vehicle

2019 ◽  
Vol 25 (18) ◽  
pp. 2423-2434 ◽  
Author(s):  
Xiaohui Zhang ◽  
Yuhui Wang ◽  
Xingkai Feng ◽  
Yunxin Li
Keyword(s):  
Degrees Of Freedom ◽  
Flight Dynamics ◽  
Damage Analysis ◽  
Flight Vehicle ◽  
Coupling Equation ◽  
Hypersonic Flight Vehicle ◽  
Hypersonic Flight ◽  
Text Model ◽  
The Relationship ◽  
Dynamic Damage

The main aim of this paper is to establish the relationship between the airfoil flutter with the flight dynamics of a generic hypersonic flight vehicle (HFV) and analyze the airfoil damage variation during the airfoil flutter. Based on the motion equations of the two degrees of freedom airfoil model and the longitudinal dynamics of the HFV, an airfoil dynamic model is established. By using a coupling equation, the relationship between airfoil flutter and the flight dynamics is estimated. According to the stress–strain ([Formula: see text]) model and the strain–fatigue damage ([Formula: see text]) model, the influence of the stress on the airfoil flutter damage is analyzed. The simulation results show that the flutter of the airfoil is closely related to the flight dynamics for the HFV and the airfoil flutter damage is closely related to the flutter amplitude of the airfoil.

Ice-crystal/shock-layer interaction in hypersonic flight

AIAA Journal ◽  
1977 ◽  
Vol 15 (10) ◽  
pp. 1511-1514
Author(s):  
T. C. Lin ◽  
N. A. Thyson
Keyword(s):  
Shock Layer ◽  
Ice Crystal ◽  
Layer Interaction ◽  
Hypersonic Flight

The motion of a lunar orbiter

1966 ◽  
Vol 25 ◽  
pp. 373
Author(s):  
Y. Kozai
Keyword(s):  
Degrees Of Freedom ◽  
Dimensional Space ◽  
Artificial Satellite ◽  
Equations Of Motion ◽  
Triaxial Ellipsoid ◽  
The Moon ◽  
Secular Motion ◽  
The Earth ◽  
Close Satellite ◽  
The Mean

The motion of an artificial satellite around the Moon is much more complicated than that around the Earth, since the shape of the Moon is a triaxial ellipsoid and the effect of the Earth on the motion is very important even for a very close satellite.The differential equations of motion of the satellite are written in canonical form of three degrees of freedom with time depending Hamiltonian. By eliminating short-periodic terms depending on the mean longitude of the satellite and by assuming that the Earth is moving on the lunar equator, however, the equations are reduced to those of two degrees of freedom with an energy integral.Since the mean motion of the Earth around the Moon is more rapid than the secular motion of the argument of pericentre of the satellite by a factor of one order, the terms depending on the longitude of the Earth can be eliminated, and the degree of freedom is reduced to one.Then the motion can be discussed by drawing equi-energy curves in two-dimensional space. According to these figures satellites with high inclination have large possibilities of falling down to the lunar surface even if the initial eccentricities are very small.The principal properties of the motion are not changed even if plausible values ofJ3andJ4of the Moon are included.This paper has been published in Publ. astr. Soc.Japan15, 301, 1963.

Representing utility and deploying the body

2020 ◽  
Vol 43 ◽  
Author(s):  
David Spurrett
Keyword(s):  
Functional Activity ◽  
Degrees Of Freedom ◽  
The Body ◽  
Target Article ◽  
Processing Demands ◽  
The Many

Abstract Comprehensive accounts of resource-rational attempts to maximise utility shouldn't ignore the demands of constructing utility representations. This can be onerous when, as in humans, there are many rewarding modalities. Another thing best not ignored is the processing demands of making functional activity out of the many degrees of freedom of a body. The target article is almost silent on both.

Das Experten-Novizen-Paradigma und die Vertrauenskrise in der Psychologie

2016 ◽  
Vol 23 (4) ◽  
pp. 131-140 ◽  
Author(s):  
Philip Furley ◽  
Karsten Schul ◽  
Daniel Memmert
Keyword(s):  
Degrees Of Freedom

Zusammenfassung. Das Ziel des vorliegenden Beitrages ist es anhand eines vielverwendeten Paradigmas in der Sportwissenschaft – dem Experten-Novizen-Vergleich – zu prüfen, ob die momentane Vertrauenskrise in der Psychologie ebenfalls die Sportpsychologie betreffen könnte. Anhand einer exemplarischen Studie zeigen wir, dass es innerhalb dieses Paradigmas zu kontroversen Befunden kommt, welche durch die vermuteten Ursachen der Vertrauenskrise (Researcher Degrees of Freedom, kleine Stichprobengrößen) erklärt sein könnten. Zusätzlich argumentieren wir, dass weitere Faktoren (Konfundierung, Stichprobengrößen, Rosenthal Effekt, Expertise-Definition) innerhalb dieses Paradigmas die Reproduzierbarkeit von Erkenntnissen in Frage stellen. Wir diskutieren mögliche Maßnahmen, wie die dargestellten Probleme des Experten-Novizen-Paradigmas in zukünftigen Forschungsarbeiten gelöst werden können.

Joint Angle Determinants in Aimed Arm Movements With Excess Degrees of Freedom

1992 ◽  
Author(s):  
Charles E. Wright ◽  
Rebecca States
Keyword(s):  
Degrees Of Freedom ◽  
Joint Angle ◽  
Arm Movements
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