Download PDF Vibration Simulation Using MATLAB and ANSYS by Michael R. Hatch

Sinopsis

This book has three main purposes. The first purpose is to cc..-ct in one document the various methods of constructing and representing dynamic mechanical models. The second purpose is to help the reader develop a strong understanding of the modal analysis technique, where the total response of a system can be constructed by combinations of individual modes of vibration. The third purpose is to show how to take the results of large finite element models and reduce the size of the model (model reduction), extracting lower order state space models for use in MATLAB.

We will see that the nature of damping in the system will determine which representation will be required. In lightly damped structures, where the damping comes from losses at the joints and the material losses, we will be able to use “modal analysis,” enabling us to restructure the problem in terms of individual modes of vibration with a particular type of damping called “proportional damping.” For systems which have significant damping, as in systems with a specific “damper” element, we will have to use the original, coupled differential equations for solution.
 

The left-hand block in represents a damped dynamic model with coupled equations of motion, a set of initial conditions and a definition of the forcing function to be applied. If damping in the system is significant, then the equations of motion need to be solved in their original form. The option of using the normal modes approach is not feasible. The three methods of solving for time and frequency domain responses for highly damped, coupled equations are shown.

Content

1. INTRODUCTION
2. TRANSFER FUNCTION ANALYSIS
3. FREQUENCY RESPONSE ANALYSIS
4. ZEROS IN SISO MECHANICAL SYSTEMS
5. STATE SPACE ANALYSIS
6. STATE SPACE: FREQUENCY RESPONSE, TIME DOMAIN
7. MODAL ANALYSIS
8. FREQUENCY RESPONSE: MODAL FORM
9. TRANSIENT RESPONSE: MODAL FORM
10. MODAL ANALYSIS: STATE SPACE FORM
11. FREQUENCY RESPONSE: MODAL STATE SPACE FORM
12. TIME DOMAIN: MODAL STATE SPACE FORM
13. FINITE ELEMENTS: STIFFNESS MATRICES
14. FINITE ELEMENTS: DYNAMICS
15. SISO STATE SPACE MATLAB MODEL FROM ANSYS MODEL
16. GROUND ACCELERATION MATLAB MODEL FROM ANSYS MODEL
17. SISO DISK DRIVE ACTUATOR MODEL
18. BALANCED REDUCTION
19. MIMO TWO-STAGE ACTUATOR MODEL

Click here to download