American institute of aeronautics and astronautics 12700 sunrise valley drive, suite 200 reston, va 201915807 703. The nonlinear model, methods of solution and typical theoretical results. Experiments on vertical slender flexible cylinders clamped. Cosine the cosine is the ratio expressed by dividing the side adjacent to the angle. A nonlinear model is presented, based on the corresponding linear equation of motion, for dynamics of the cylinder supported at both ends. Flexible launch vehicle stability analysis using steady.
Attitude control of a flexible launch vehicle is addressed in this study. Pdf theoretic analysis and experiment on aeroelasticity. Stability analysis of specialshape arch bridge wenliang qiu1, chinsheng kao2, changhuan kou3, jenglin tsai3 and guang yang1 1school of civil engineering, dalian university of technology, dalian city, liaoning province 116024, p. Continuation of equilibria and stability of slender.
Experimental investigation of the response performance of viv on a flexible riser with helical strakes. Pdf aeroelastic stability of a slender missile with. Within the applied research of the faculty of civil engineering at slovak university of technology in bratislava in cooperation with the company zipp bratislava ltd the experimental. Nonlinear dynamics of a slender flexible cylinder subjected. The column is loaded with a vertical force p that is applied through the centroid of the cross section and aligned with the longitudinal axis of the column. For the verification of nonlinear design methods it is important to compare their results with results of experiments. Just like a garden hose delivering a high turbulent. Aeroelastic stability has been a concern since early development of the saturn i 5,6.
When the cantilever is sufficiently slender, typically for a cantilever. Paoussis department of mechanical engineering, mcgill university, montreal, quebec, canada h3 c 3g1 received 20 december 1974 a theoretical analysis is presented of the dynamical behaviour of flexible cylinders in axial flow, the velocity of which is perturbed harmonically. The weakly nonlinear equations of motion for a slender flexible cylinder of length l, diameter d and mass per unit length m, subjected to axial flow with flow velocity u and added mass per unit length, in unconfined flow, m, have been derived by modarressadeghi et al. I magine the benefits that battlefield commanders or intelligence analysts could derive from an airborne surveillance platform that would carry a 500pound. Experimental analysis of slender concrete columns at the. The phrases core stability, shoulder stability, and hip stability are all common uses of this term in the yoga world. This study focuses on the response of axially moving beamlike elements at translation speeds that exceed the classical critical speed stability limit. Analytical modeling of chatter stability in turning and. 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. Request pdf dynamic stability of deep and slender wideflange steel columns full scale experiments in north america, a common design practice for steel frame buildings with perimeter steel. International journal of structural stability and dynamics. Fluidstructure interactions of wallmounted flexible slender. The nonlinear terms considered here are the quadratic viscous force and the additional axial force induced by the lateral motions of the cylinder. Paoussis department of mechanical engineering, mcgill university, montreal, quebec, canada h3 c 3g1 received 20 december 1974 a theoretical analysis is presented of the dynamical behaviour of flexible cylinders in axial flow, the velocity of which is perturbed.
Kurnik and przybyowicz 14 have studied on an extended problem of the stability of leipholzs slender column with rotation effect taken into account. The stability of a flexible cantilever in viscous channel flow. Stability of aeroelastic airfoils with camber flexibility fun3d nasa. Stability and dynamics of the laminar wake past a slender. In the previous papers, the axisymmetric rods are regarded as rigid bodies, not as continuous bodies. An influencecoefficient approach to static aeroelastic problems and a comparison with experiments on a flexible windtunnel model by. Stability and dynamic analysis of a slender column with. Two types of aerodynamic loads are assumed in the stability analysis. Stability of slender beams and frames resting on 2d. Hence, a tether dynamics experiment tde was formed and. It is an obvious requirement that a floating body such as a boat does not topple when slightly disturbed.
Allsolid flexible fibershaped lithium ion batteries. Aeroelastic stability of a slender missile with constant thrust. The final qualification steps, known as the balloon launched decelerator test program. Stability becomes an important consideration when floating bodies such as a boat or ferry is designed. Very flexible slender wings with deformable airfoils, 49th aiaa. At large scales, the rod can be regarded as an adapted material curve. Request pdf dynamic stability of deep and slender wideflange steel columns full scale experiments pin north america, a common design practice for steel frame buildings with perimeter steel. A general theory is presented to account for the small, free, lateral motions of a flexible, slender, cylindrical body with tapered ends, totally submerged in liquid and towed at steady speed u. Journal of sound and vibration 1975 421, 111 stability of flexible slender cylinders in pulsatile axial flow m. Vibration control of flexible beams using sensor averaging. Microscopic artificial swimmers have recently become highly attractive due to their promising potential for biomedical applications. An elastic rod is a slender elastic body which has a length along one spatial direction that is much larger than its dimensions in the two other perpendicular directions, that define the cross section fig.
Nonlinear parametric excitation effect induces stability transitions in swimming direction of flexible superparamagnetic microswimmers yuval harduf 1, dongdong jin2, yizhar or and li zhang2,3 abstract. This dissertation describes the development of an experimental procedure which leads to a feature stability theory. Quantitative comparison of the various instability thresholds and stable zones between experiment. Accordingly, the probability density functions of the modal data are derived for damage detection. In order to study the thrust effects of slender, flexible missile comprehensively, the work of this paper survey the constant thrust effects on transverse vibration, structure dynamic stability and aeroelastic stability, which would supply instructions for engineering experiments and modeling of flying. Making use of a mixed variational formulation based on the green function of the substrate, which assumes as independent fields the structure displacements and the contact pressure, a simple and efficient finite elementboundary integral equation coupling method is derived and applied to the stability analysis of beams and frames resting on an elastic halfplane. Coupled flight dynamics, aeroelasticity and control, cambridge press, new york, in. The results are compared with a classical waving flag result in twodimensional flow. Effect of aerodynamic loads on dynamic stability of.
Flutter prediction, suppression and control in aircraft. Stability of towed, totally submerged flexible cylinders. The calculation of lateral stability derivatives of slender wings at incidence, including fin effectiveness, and correlation with experiment by a. Pdf of segment reynolds number based on slip velocity in hit. Dynamic stability of deep and slender wide flange steel. Pdf studies on aeroservoelasticity semiphysical simulation test. Shearer, usaf the author is an assistant professor in the aeronautical and astronautical department, air force institute of technology, wrightpatterson afb, ohio. Stability of towed, totally submerged flexible cylinders volume 34. Any flexible rotor with permanent energy supply maintaining a constant rotation speed starts to exhibit orbital motion of its deflected form around the axis placed between the supports. For particular shapes of the ends and length of towrope, it is shown that the body may be subject to oscillatory and nonoscillatory instabilities for u 0. Theoretic analysis and experiment on aeroelasticity of very fl exible wing. Nonlinear dynamics of a slender flexible cylinder in axial. Jaworski department of mechanical engineering and materials science duke university date.
Axially moving material problems consider the dynamic response, vibration and stability of long, slender members which are in a state of translation. Flutter of slender bodies under axial stress springerlink. Yet, the starting point in any hydrodynamic stability. Firstly, it is assumed that two concentrated aerodynamic loads act on the flight body at its nose and tail.
The slender body result for the flutter speed is compared with values obtained from wind tunnel. The structure is modeled by a completely undamped shear beam model. Stability of flexible slender cylinders in pulsatile axial. Nonlinear aeroelastic analysis of complete aircraft in. Perhaps the most common understanding of stability is not moving or stillness. Theory and experiment agree qualitatively in most essential features of the dynamical behaviour of the. Nonlinear aeroelastic analysis of flexible high aspect ratio wings including correlation with experiment by justin w. Open loop transfer function test and closed loop stability test are carried out in sequence. Paidoussisdynamics and stability of flexible cylinders subjected to liquid. The governing equation for a geometrically perfect column is eiwiv.
The design is a combination of the classical damping boundary feedback idea with backstepping boundary control. Both theory and experiment show that with increasing flow the system loses. Axial leakage flowinduced vibration of the elastic rod as. Communicated by the deputy controller aircraft research and development, ivinistry of aviation reports and memoranda no. Note on the swimming of slender fish, journal of fluid. Although conceptually similar, the stability and dynamical properties of the. Concept of structural stabilityinstability key item is transition, with increasing load, from a stable mode of deformation stable equilibrium for all possible small displacements. Dynamics and stability of spinning flexible space tether systems. The dynamics of flexible slender circular cylinders in axial flow having regard to their fluidelastic instability characteristics is an extensively studied problem in the literature. The fluidstructure interactions of wallmounted slender structures, such as cilia.
The dynamic stability derivat ives of a slender wing, a comparison of theory with freeflight model tests at nearzero. Stability of towed, totally submerged flexible cylinders journal of. A ground experimental model is developed for verification of different stabilization strategies. Buoyancy and s tability of a floating body 3 school of engineering science mechatronic systems engineering the floating object is stable when the metacentric height. An investigation into the hydrodynamics of a flexible riser undergoing vortexinduced vibration. Full text views reflects the number of pdf downloads, pdfs sent to. The experimental set up duplicates planar motion of flexible launch vehicles as a coupled hybrid dynamics of rigid body pitching motion and flexible vibration. Stability of a floating body principle a floating body is said to be stable at its position, if it returns to that position following a small disturbance.
Dynamic stability of deep and slender wide flange steel columns full scale experiments ahmed elkady1, dimitrios g. Flight dynamics of highly flexible flying wings journal. Wakebody resonance of long flexible structures is dominated by counterclockwise. Maynard, who tested both rigid and flexible parachute models. The stability based on the stiffness of the fiber segments is derived as follows 69. The flexible booms typically used on spacecraft are long and slender with a. Numerical modeling of long flexible fibers in inertial flows. The evaluation methodologies for the flowinduced vibration instability of a long flexible rod due to axial leakageflow are reported. The test object is a flexible slender missile model with. We identify a dominant mechanism in the interaction between a slender flexible structure undergoing. Lignos2 abstract in north america, a common design practice for steel frame buildings with perimeter steel special moment frames smfs is to employ deep and slender wideflange steel columns i.
This work is motivated by the interests in stabilizing vibrating slender bodies. The stability of a flexible cantilevered plate subjected to an axial flow is investigated. The dynamic stability derivatives of a slender wing, a. A finite element formulation of the problem is presented in this paper. China 2department of civil engineering, tamkang university, tamsui, taiwan 251, r. We denote the typical size of the crosssection by h and the other length scale by l. Aerodynamic stability and performance of nextgeneration. A method for nonlinear aeroelasticity trim and stability analysis of very flexible aircraft based on corotational theory journal of fluids and structures, vol. The dynamics and stability of a pinnedfree cylinder in axial. Nonlinear aeroelastic analysis of flexible high aspect. To investigate the stability behavior of columns, we will begin by considering a long slender column with pinned joints at each end. Dynamic stability of deep and slender wideflange steel. An influencecoefficient approach to static aeroelastic. The use of nonlinear methods for design of slender concrete columns by european standards.
Flexible long slender wing standing large aerodynamic. Introduction laboratory experiment 2 is an exercise in hydrostatics. Stability and dynamics of the laminar wake past a slender bluntbased axisymmetric body p. The proof of concept experiment showed us that it is possible to obtain several milliwatts s of power using the centimeter scale device, with an output power of. The dynamics of clusters of flexible cylinders in axial flow. Theory and experiment for flutter of a rectangular plate with a fixed leading edge in three. In this paper an experimental investigation into the stability of a largescale, curved, 3span bridge model isolated by 12 leadrubber bearings is described. Aeroelastic stability of a slender missile with constant. Indeed, if the pipe used in the experiment is highly flexible, then it is possible to store work in the system the pipe by temporarily curving it. Paidoussisdynamics of flexible slender cylinders in axial flow. The equations of motion of flexible slender bodies with constant body sections immersed in a uniform axial flow are discussed and used to derive some simple results for the divergence speed and the flutter speed. The stability and nonlinear dynamics are studied for a slender flexible cylinder subjected to axial flow.
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