• Svenska

# SD2110 Introduction to Noise Control 3.0 credits

The course covers the fundamentals of the science of sound and vibration.

### Choose semester and course offering

Choose semester and course offering to see current information and more about the course, such as course syllabus, study period, and application information.

## Application

### For course offering

Autumn 2024 Start 28 Oct 2024 programme students

### Application code

50271

Headings with content from the Course syllabus SD2110 (Spring 2022–) are denoted with an asterisk ( )

## Content and learning outcomes

### Course contents

Definition of sound – sound pressure and velocity. Upper, mean, mean square and root mean square values. Frequency, period, wave length, wave number, phase velocity. Plane, cylindrical and spherical waves.

Diffraction of waves – Huygen’s Principle. Reflection of waves. D’Alembert Principle. Harmonic and periodic signals. Fourier series analysis. Frequency spectrum – audible frequency range, octave band, one-third octave band, upper and lower frequency limit, band-width, centre frequency. Frequency filter – low-pass, high-bass, band-pass and band-stop filters. Measures of sound – sound pressure, sound intensity and sound power levels. Addition of sound fields – correlated and uncorrelated sources. Addition of frequency components. Weighted frequency spectrum – A, B, C and D-filters.

Standing and travelling waves. Longitudinal and transversal waves in infinite solids. Wave equation and its solutions in fluids.

### Intended learning outcomes

After the course, the participant shall be able to:

• Know basic acoustic definitions:
- Define peak value of sound pressure.
- Define mean value of sound pressure.
- Define root mean square value of sound pressure.
• Comprehend basic wave types in fluids:
- Explain the characteristics of plane waves.
- Give an example of plane waves from the ‘real world’.
- Explain the characteristics of cylindrical waves.
- Give an example of cylindrical waves from the ‘real world’.
- Explain the characteristics of spherical waves.
- Give an example of spherical waves from the ‘real world’.
• Comprehend basic wave types in infinite solids:
- Explain the characteristics of longitudinal waves.
- Give an example of longitudinal waves from the ‘real world’.
- Explain the characteristics of transversal waves.
- Give an example of transversal waves from the ‘real world’.
• Comprehend Huygen’s Principle:
- State the principle in his or her own words.
- Identify an example of the principle.
• Comprehend D’Alembert Principle:
- State the principle in his or her own words.
- Identify an example of the principle.
- Predicts an outcome based on the principle for harmonic waves.
• Apply acoustical methods to new situations:
- Predict the total A-weighted sound power level for the whole audible frequency range from known third-octave band levels
- Calculate the harmonic components of an arbitrary periodic signal
- Computes the resulting sound level of a broad band sound when passed through a frequency filter
• Synthesize complex waves from simple waves:
- Combines longitudinal and transversal waves to form bending waves
- Creates standing waves from travelling waves using reflections
- Combines longitudinal and transversal waves to form quasi-longitudinal waves
• Comprehend the wave equation:
- Derive the wave equation in fluids
- Determine the solution of wave equation in fluids:

## Literature and preparations

### Specific prerequisites

Basic courses in mechanics and mathematics.

English B / English 6

### Recommended prerequisites

No information inserted

### Equipment

No information inserted

### Literature

No information inserted

## Examination and completion

If the course is discontinued, students may request to be examined during the following two academic years.

P, F

### Examination

• TEN1 - Examination, 3.0 credits, grading scale: P, F

Based on recommendation from KTH’s coordinator for disabilities, the examiner will decide how to adapt an examination for students with documented disability.

The examiner may apply another examination format when re-examining individual students.

### Other requirements for final grade

Oral examination (TEN1; 3 university credits).

### Opportunity to complete the requirements via supplementary examination

No information inserted

### Opportunity to raise an approved grade via renewed examination

No information inserted

### Ethical approach

• All members of a group are responsible for the group's work.
• In any assessment, every student shall honestly disclose any help received and sources used.
• In an oral assessment, every student shall be able to present and answer questions about the entire assignment and solution.

## Further information

### Course room in Canvas

Registered students find further information about the implementation of the course in the course room in Canvas. A link to the course room can be found under the tab Studies in the Personal menu at the start of the course.

### Main field of study

This course does not belong to any Main field of study.

### Education cycle

Second cycle

SD2165 Acoustical Measurements
SD2150 Experimental Structure Dynamics
SD2155 Flow Acoustics
SD2175 Numerical Methods for Acoustics and Vibration
SD2180 Non-Linear Acoustics
SD2190 Vehicle Acoustics and Vibration

### Contact

Leif Kari, leifkari@kth.se, tel. 790 7974

### Supplementary information

Not scheduled and can be taken during all periods.

The course SD2110 cannot be counted in your Degree if you have studied SD1116, SD1120, and SD2111.