Dynamic stability of free-free beam subjected to end rocket thrust and carrying a heavy payload at its nose

2004 ◽  
Author(s):  
T. Ohshima ◽  
Y. Sugiyama
Keyword(s):  
Dynamic Stability ◽  
Rocket Thrust ◽  
Free Beam

Effect of Aerodynamic Loads on Dynamic Stability of Slender Launch Vehicle Subjected to an End Rocket Thrust

2002 ◽  
Author(s):  
Tsukasa Ohshima ◽  
Yoshihiko Sugiyama
Keyword(s):  
Stability Analysis ◽  
Dynamic Stability ◽  
Longitudinal Axis ◽  
Launch Vehicle ◽  
Aerodynamic Load ◽  
Aerodynamic Loads ◽  
Eigen Values ◽  
Rocket Thrust ◽  
The Stability ◽  
Free Beam

This paper deals with dynamic stability of a slender launch vehicle subjected to aerodynamic loads and an end rocket thrust. The flight vehicle is simplified into a uniform free-free beam subjected to an end follower thrust. Two types of aerodynamic loads are assumed in the stability analysis. Firstly, it is assumed that two concentrated aerodynamic loads act on the flight body at its nose and tail. Secondly, to take account of effect of unsteady flow due to motion of a flexible flight body, aerodynamic load is estimated by the slender body approximation. Extended Hamilton’s principle is applied to the considered beam for deriving the equation of motion. Application of FEM yields standard eigen-value problem. Dynamic stability of the beam is determined by the sign of the real part of the complex eigen-values. If aerodynamic loads are concentrated loads that act on the flight body at its nose and tail, the flutter thrust decreases by about 10% in comparison with the flutter thrust of free-free beam subjected only to an end follower thrust. If aerodynamic loads are distributed along the longitudinal axis of the flight body, the flutter thrust decreases by about 70% in comparison with the flutter thrust of free-free beam under an end follower thrust. It is found that the flutter thrust is reduced considerably if the aerodynamic loads are taken into account in addition to an end rocket thrust in the stability analysis of slender rocket vehicle.

STABILITY OF A JOINTED FREE–FREE BEAM UNDER END ROCKET THRUST

1997 ◽  
Vol 199 (1) ◽  
pp. 1-15 ◽  
Author(s):  
K.A. Mladenov ◽  
Y. Sugiyama
Keyword(s):  
Rocket Thrust ◽  
Free Beam

Dynamic Stability Characteristics of Axially Accelerated Beams

2006 ◽  
Vol 321-323 ◽  
pp. 1654-1658 ◽  
Author(s):  
Hong Hee Yoo ◽  
Sung Jin Eun
Keyword(s):  
Dynamic Stability ◽  
Natural Frequencies ◽  
Equations Of Motion ◽  
Stability Diagram ◽  
Accelerated Motion ◽  
Stability Diagrams ◽  
Divergence Type ◽  
The Stability ◽  
Direct Numerical Integration ◽  
Free Beam

Dynamic stability of axially accelerated beams is investigated in this paper. The equations of motion of a fixed-free beam undergoing axially accelerated motion are derived. Unstable regions due to the acceleration are obtained by using the Floquet’s theory. Stability diagrams are presented to illustrate the influence of the acceleration characteristics. Large unstable regions of flutter type instability exist around the first, twice the first, and twice the second bending natural frequencies. Divergence type instability also occurs when the acceleration exceeds a certain value. The validity of the stability diagram is confirmed by direct numerical integration of the equations of motion.

Molecular insights on the dynamic stability of peptide nucleic acid functionalized carbon and boron nitride nanotubes

2021 ◽  
Vol 23 (1) ◽  
pp. 219-228
Author(s):  
Nabanita Saikia ◽  
Mohamed Taha ◽  
Ravindra Pandey
Keyword(s):  
Nucleic Acid ◽  
Boron Nitride ◽  
Nucleic Acids ◽  
Dynamic Stability ◽  
Peptide Nucleic Acid ◽  
Rational Design ◽  
Peptide Nucleic Acids ◽  
Boron Nitride Nanotubes ◽  
Molecular Hybrids ◽  
Single Wall Nanotubes

The rational design of self-assembled nanobio-molecular hybrids of peptide nucleic acids with single-wall nanotubes rely on understanding how biomolecules recognize and mediate intermolecular interactions with the nanomaterial's surface.

When Rows Look Like Columns: Dynamic Stability of Grouping by Proximity

2000 ◽  
Author(s):  
Helena Kadlec ◽  
Iris Van Rooij ◽  
Valerie A. Gonzales
Keyword(s):  
Dynamic Stability

Control of Steam-Turbine Regulators at Transition to an Island State

2009 ◽  
Vol 25 (25) ◽  
pp. 73-76
Author(s):  
Georgi Georgiev
Keyword(s):  
Steam Turbine ◽  
Dynamic Stability ◽  
Easy Problem ◽  
Island State ◽  
On Line ◽  
State Regime ◽  
Turbine Speed ◽  
The Given ◽  
Operating Algorithm

Control of Steam-Turbine Regulators at Transition to an Island StateThe simple operating algorithm is presented for steam turbine regulators of type Simadin (Siemens) at emergency switching-off of the generator from system together with some, unknown in advance, load. The given situation is known as "a transition to an island state (regime)". Keeping of turbine speed and preservation of its rating value at a generator blackout when its own needs will be load only, is an easy problem. When the generator remains in its island it is necessary to solve "on-line" two additional problems: to reveal a situation "island" and to estimate the island load for translating a regulator on the new task and providing dynamic stability of transition. The algorithm was tried and entered successfully into practice on Varna TPP, CEZ GROUP (Prague), in 2008.

Sign in / Sign up

Export Citation Format

Share Document