Modal analysis of a nonuniform string with end mass and variable tension

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National Aeronautics and Space Administration, Scientific and Technical Information Branch, For sale by the National Technical Information Service] , Washington, D.C, [Springfield, Va
Structural analysis (Engineering), Structural engine
StatementMario H. Rheinfurth and Zachary J. Galaboff
SeriesNASA technical paper -- 2198
ContributionsGalaboff, Zachary J, United States. National Aeronautics and Space Administration. Scientific and Technical Information Branch
The Physical Object
Paginationiii, 20 p. :
ID Numbers
Open LibraryOL14933421M

Modal analysis of a nonuniform string with end mass and variable tension. Washington, D.C.: National Aeronautics and Space Administration, Scientific and Technical Information Branch.

Modal analysis of a nonuniform string with end mass and variable tension / (Washington, D.C.: National Aeronautics and Space Administration, Scientific and Technical Information Branch.

Reduced-order mass weighted proper orthogonal decompo-sition (RMPOD), smooth orthogonal decomposition (SOD), and state variable modal decomposition (SVMD) are used to extract modal parameters from a nonuniform experimen-tal beam.

The beam was sensed by accelerometers. Ac-celerometer signals were integrated and passed through a high-pass filter. A nonuniform, horizontal bar of mass m is supported by two massless wires against gravity. The left wire makes an angle ϕ1 with the horizontal, and the right wire makes an angle bar has length L.

(Figure 1) Part A Find the position of the center of mass of the bar, x, measured from the bar's left end. Express the center of mass in terms of L, ϕ1, and ϕ2. Modal Analysis of Interpolation Constraint Elements and Concentrated Mass Model Description: The goal of this example is to examine the effect of rigid and interpolation contraint elements.

The rigid element, RBE2, will maintain a circular cross section at the rigid end of the tube, while the interpolation constraint. It depends on the properties you are evaluating.

For example, if you are working on the influence of superior modes in the structure's response, it would be better consider more than three. A rod of length L and mass M has a nonuniform mass distribution. The linear mass density (mass per length) is λ=cx2, where x is measured from the center of the rod and c is a constant.

What are the units of c. Mastering physics says the answer is: kg/m^3 but i don't understand where they got this answer. The vibration of continuous structures [Ch.

4 where o = clwavelength. These are the natural frequencies. If the initial displacement is zero, D = 0 and where B = B x C.

Hence the mode shape is determined. Example 30 A uniform vertical rod of length 1 and cross-section S is fixed at the upper end and is. Abstract This thesis presents two novel nonlinear modal analysis methods, aimed at the identification of representative engineering structures.

The overall objective is to detect, localize, identify and quantify theCited by: Table 1: Parameters of the nonuniform string Parameter Description Value L Length of string 1m (x) Mass per unit length (x + 5)kg/m Ms Mass of the tip payload 1kg T0 (x) Initial tension 10(x + 1)N (x) Elastic modulus (x + 1) m d where µ4 = min(µ3, 2, t, 2) is a positive constant and 2 m d¯ = 2 Ms 2 + t T0 2 (L) + 2 d2 +.

Details Modal analysis of a nonuniform string with end mass and variable tension PDF

2 Cited by: 1. Modal Analysis of Interpolation Constraint Elements and Concentrated Mass MSC/NASTRAN Exercise Workbook - Version 70 (MSC/PATRAN ) Proceed with the Reverse Translation process, that is importing the lessonop2 results file into MSC/PATRAN. To do this, return to the Analysis form and proceed as follows:   This is just a practice problem, not actual homework.

I'm studying for my final but am having a bit of difficulty in understanding this concept. Homework Statement Consider a solid of non-uniform density ρ=x2+y+z, consisting of all points inside the sphere x2+y2+z2=1 a) Find the mass of the. The method is highly accurate and computationally efficient, as verified by comparison with other techniques such as exact theory, modal analysis method, and.

A cantilevered beam of length L and mass M b, is clamped at x = 0 and loaded at its free end by a concentrated mass M which is assumed to be much larger than M b (see Figure ). In such a system, most of the kinetic energy is related to the motion of the end mass and most of the potential energy is related to the bending of the : François Axisa, Philippe Trompette.

A nonuniform bar is suspended at rest in a horizontal position by two massless cords. On cord makes the angle θ = ° with the vertical; the other makes the angle φ = ° with the vertical. If the length L of the bar is m, compute the distance x from the left-hand end of the bar to its center of mass.

The Answers is m but I don't know how to get this. Modal Analysis - Free download as Powerpoint Presentation .ppt /.pptx), PDF File .pdf), Text File .txt) or view presentation slides online. modal analysis. ximate solutions for the static and dynamic behaviour of nonuniform beams.

Using Ritz method, Sato [1] studied the transverse vibration of linearly tapered beams. Lee and Ke [2] proposed a fundamental solution for nonuniform beams with general end conditions. Vi-bration of nonuniform beams was analysed by Abrate [3] by transforming the equation of. A compact two-dimensional finite-difference time-domain method is developed for the modal analysis of nonuniform dielectric waveguides.

The unsplit-field perfectly-matched-layer absorbing boundary condition has also been extended to this approach. The proposed method approximates the maxwell equations by using the semivectorial wave equations, and the Cited by: 2. Modal Mass is very low A0 = g. V0 = 12 ft/s. Modal Mass is very high A0 = 50 g.

V0 = 4 ft/s. Input Acceleration will be in this range, dependent on Modal Mass. (After Scavuzzo and Pusey ; Naval S hock Analysis and Design SAVIAC )File Size: 2MB.

In case of uniform velocity, both the magnitude and direction of velocity is constant. If the velocity is not uniform, either the magnitude or direction or both change. Some examples of non-uniform velocity are 1. Uniform circular motion - the mag.

2 MODAL ANALYSIS PROCEDURE BASED ON THE MASS NORMALIZED COMPLEX RIGHT EIGENVECTORS The procedure, briefly reviewed here, has been presented in details in [2] – [4]. The single mass oscillator The equation of motion of a damped single degree of freedom system (SDOFS) (b) canFile Size: 1MB.

Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It only takes a minute to sign up. If the mass distribution is uniform, the POD produces the normal modes of a structure [27{30], including 2-D structures [31].

If the mass distribution is not uniform, but known, or if the stifiness matrix is known, the POD can be weighted to produce the normal modes [27]. POD can be used for modal analysis if the damping is light, and if the Cited by: Complex Non-Linear Modal Analysis for Mechanical Systems: Application to Turbomachinery Bladings With formalism of the complex non-linear modal analysis method.

The third illustrates it on a two for which the implicit variable z reprensents the displacement of. Example Problem A top spins at 30rev/s about an axis that makes an angle of 30 deg with the vertical.

The mass of the top is kg, the rotational inertia is kgm2, and its center of mass is 4cm from the pivot point.

Description Modal analysis of a nonuniform string with end mass and variable tension PDF

If the spin is clockwise from an overhead view, what are the a) precession rate?File Size: KB. Uniform Acceleration and Non-uniform Acceleration by Heba Soffar Published Febru Updated Septem If the velocity of an object is changed from one point to another either in magnitude or direction, This change in velocity with time is known as acceleration and such motion is called accelerated motion.

One cord makes the angle θ = ° with the vertical; the other makes the angle φ = ° with the vertical. If the length L of the bar is m, compute the distance x from the left end of the bar to its center of mass. tension in the string (T), the normal force (N) of the constraining k M W ℓ X Figure A more general end condition for a string.

Transverse Vibrations of Strings kw (ℓ, t) N Q M T w (ℓ, t) Equilibrium position Figure A free body diagram of a mass connected at a string end and attached to a spring.

Defining Nonuniform Pressure Loads.

Download Modal analysis of a nonuniform string with end mass and variable tension PDF

To apply nonuniform pressure normal to a face: In the Simulation study tree, right-click the External Loads icon and select Pressure. The Pressure PropertyManager appears. Under Type, select Normal to selected face. In the graphics area, click the face on which the pressure is applied.

Nonlinear modal analysis of a one-dimensional bar undergoing unilateral contact via the time-domain boundary element method Jayantheeswar Venkatesh, Anders Thorin, Mathias Legrand To cite this version: Jayantheeswar Venkatesh, Anders Thorin, Mathias Legrand. Nonlinear modal analysis of a one-Cited by: 1.

The stiffness of externally pressurized air bearing is nonlinear, so it is difficult for nonlinear modeling and modal analysis with Finite Element Modal Analysis(FEMA). In this paper, the spring-mass system method which use linear springs in place of nonlinear air bearing has been developed to make FEMA of externally pressurized air bearing workbench more easier and Author: Bo Zhang, Ping Ma, J.J.

Huang.The ABAQUS analysis cannot be executed. Attached is my input file. Can anyone tell me what I have done wrong? Any other instruction as to the best way to do this or what the various option mean/the right thing to put in when you are using Abaqus CAE would be very much appreciated. Thank you for your time, Liz modal_analysis_17_inp.Modal Analysis of CSLDV Measurements Using the Multiple Discrete Time Systems Method The signal y(t) measured by a scanning LDV on a freely vibrating, linear, time-invariant structure, can be expressed as a sum of decaying exponentials in terms of the state space modal parameters of the structure as follows () () 2 1 22, 1, 1 r = +.