MEEN 617 - Mechanical Vibrations – SPRING 2008
Dr. Luis San Andrés

Last update:
April 11, 2008, assumed modes method – Handwritten notes,
                      HD 15 – Identification of parameters in mechanical systems
March 28, 2008, HD 13 Numerical integration MDOF systems

March 21, 2008: handout 14 vibes of continuum systems + addendum to HD 9
March 17, 2008: handout 9 evaluation of eigenvalues
March 3, 2008: handouts (6,7,8,11), Issues with FRF
January 23, 2008 (handout 4 & 10-vibration absorber)

January 16, 2008  (handouts 2c, 2d, recommended problems from textbook

 

Course Description:   Linear Theory of vibrations of Single and Multiple degree of freedom (DOF) systems via Newtonian and Lagrangian formulations, and with emphasis on analytical methods and computer applications. Prerequisites:         MEEN 364, MATH 308.

 

OBJECTIVES: To provide the fundamental analytical and numerical tools for analysis and modeling of vibration phenomena in discrete and continuum SDOF and MDOF linear systems. Learning of advanced analytical tools and methods for experimental identification of system parameters using recorded data, i.e. frequency domain parameter identification methods.

 

Class Time:  T, R 2:20 – 3:35 pm, ZACH 119D

 

Instructor: Dr. Luis San Andrés, ENPH 118, Phones : 862 4744, LsanAndres@Mengr.tamu.edu

                Office hours: T, R 10:-11:00 am, or by scheduled appointment (phone call or e-mail in advance).

 

References:    Mechanical and Structural Vibration: Theory and Applications, J. H. Ginsberg

SYLLABUS

Recommended problems from your textbook

week

chapter

Problem numbers

1

1

5, 8, 13, 14, 15, 20, 43, 44, 56

2

2

 

3&4

3

3, 7, 19, 20, 22, 25, 50, 52

5

1

Derive EOMs MODF systems: 25, 27, 30, 33, 36, 38, 39, 44, 49

6

4

10/19, 21, 30, 36, 39,34, 55

7

5

14, 18, 29

8

7

3, 11, 43, 49

10

6

3, 9, 11, 14, 15, 28, 38, 54

NEW release in 2008 - Spring

Class Notes (handouts)

            NEW Introduction to the analysis of vibrations in mechanical systems.

Introduction to motion in mechanical systems. Definition of design, analysis, and testing. Steps in Modeling. Continuous and lumped parameter systems. Second Order Systems and differential equations of motion. Definitions of Free and Forced Responses. The purpose of analysis and the relevant issues to resolve.

 

1.     NEW Handout 1 Modeling of mechanical (lumped parameter) elements

       Fundamental elements in mechanical systems: inertias, stiffness and damping elements. Equivalent spring coefficients and associated potential energy. Equivalent mass or inertia coefficients and associated kinetic energy. Equations of motion of a rigid body in a plane. Equivalent damping coefficients and associated dissipation energy. Types of damping models (linear or viscous and nonlinear).

NEW Appendix A. Equivalence of principles of conservation of mechanical energy and conservation of linear momentum.

      NEW Appendix B. Linearization

      NEW Appendix C. Derivation of equations of motion for a multiple degree of freedom system

NEW Appendix D. Note on assumed modes

NEW Appendix E. Vibration sensors and their applications

 

2.     Dynamic response of second order mechanical systems

NEW Handout 2a Free response to initial conditions: viscous and coulomb damping systems. Forced response: impulse and step loads.

NEW Handout 2b Periodic forced response and Frequency response function of second order systems.

NEW Handout 2c Interpretation of forced periodic response. Transmissibility (forces transmitted to base or foundation). Frequency Response due to base or foundation motions

NEW Handout 2d Fourier series. Forced response to a periodic forced excitation. Response to a unit impulse. Convolution integral and response to arbitrary loading (7 pages).
NEW Uses of the FRF on the design of mechanical systems

 

4.     NEW Handout 4: Elements of analytical dynamics. Work and Energy – Single particle. Constraints – degrees of freedom. Principle of virtual work. D’Alembert Principle. Hamilton Principle. Lagrange’s equations of motion. (20 pages)

 

5.     EXAMPLES:  Solutions to a bunch of 1_DOF problems: derivation of Equations of Motion and Initial Conditions in Simple Mechanical Systems, Free and Forced Responses, Frequency response Functions
(distributed via e-mail to students registered in class)

 

6.     NEW Numerical solution of EOM for a single degree of freedom (SDOF) system.  ().


Vibrations of multiple degree of freedom (MDOF) systems

7.     NEW Undamped Modal Analysis of MDOF systems: Free & Force Vibrations of undamped MDOF systems. Orthogonality properties of natural modes. Rayleigh energy methods. Mode superposition (displacement and acceleration methods)

8.     NEW  Modal Analysis of MDOF systems with Proportional Damping.
NEW Addendum: Mode acceleration method

 

 

9.     NEW Numerical evaluation of natural modes and frequencies. ().

 

10.            NEW The dynamic vibration absorber (11 p).

 

11.            NEW Modal Analysis of MDOF Systems with Viscous Damping (10 pages).

 

12.            Finite element modeling of mechanical systems (OLD).

13.            NEW Numerical methods for the dynamic response of MDOF damped systems ().

 

14.            NEW Dynamic response of continuum systems ().

OLD: Rayleigh-Ritz energy Methods (assumed modes method) – Handwritten notes

 

15.             NEW  Identification of parameters in mechanical systems

 

 


The handouts and textbook used in this course are copyrighted. By "handouts," I mean all materials generated for this class, which include but are not limited to syllabi, quizzes, exams, lab problems, in-class materials, review sheets, and additional problem sets. Because these materials are copyrighted, you do not have the right to distribute freely the handouts, unless the author expressly grants permission.


Send all comments or questions to LsanAndres@Mengr.tamu.edu