## 7.1 PREFACE

The notes are based on the book “Industrial Noise and Vibration Control” by Irwin and Graf. Whenever figures, table, questions, etc. are referred to that are not in these notes, they may be found there. The notes generally follow the order of the text, except for the vibration component of the notes. Sets of questions follow the applicable note sections, these are from previous assignments, midterms, and finals. Where available answers are provided, but at this point the only promise about their value is that they will contain mistakes (hopefully many of these mistakes will be corrected in future revisions). Please take note of mistakes in the notes, and indicate them to me later. I will upgrade the notes for the benefit of future years. Please keep track of additional topics you think would be of value, and I will endeavor to add those if possible. A set of log graph paper sheets are provided near the front of the notes. These can be used for some of the vibration, and sound problems.

A note of value is that the problems do tend to focus on industrial noise and vibration control, but the approaches discussed are directly applicable to other areas, such as vibration in an airframe.

The selection of topics, first vibration then sound might apparently seem distant at best. But, when considered, these phenomenon are natural complements. In fact the underlying mathematical concepts are identical, the major difference is that the transmission medium is varied. This rationale leads the review of vibrations concepts, to lay a familiar basis for the student to consider the nature of sound. The essential nature of these problems cannot be underplayed, as environmental issues are becoming an essential component of all engineering design. It is for this reason that the scientific properties of sound will be related to various existing legal statutes for noise control.

### 7.1.1 Theoretical Fundamentals

The student is expected to have a grasp of a number of basic topics,

- Properties of logarithms

- Laplace and Fourier transforms

- Wave properties

- A knowledge of statics and dynamics

- A basic background in material properties

- A previous course in vibration