Advanced Aircraft Noise Modelling and Measurement

The course AE4463P-23 aims at providing students with a solid background in the modelling and measurement of aircraft noise.

The course consists of lectures and a number of assignments that focus on:

A. Noise metrics

Microphone data, consisting of measured pressures as a function of time will be provided. From these data both the overall sound pressure level (OSPL) and the A-weighted OSPL should be determined as a function of time. Based on this, the Sound Exposure Level (SEL) must be calculated.

B. Digital Signal Processing (DSP)

Lecture notes on this topic will be provided. The corresponding assignments focus on resolution in the frequency domain after Fourier Transforming the time signals, the effect of weighting the signals, sampling and cyclic convolution.

C. Analog Signal Processing

Lecture notes on this topic will be provided. For circuits related to acoustic measurements, an important element is the operational amplifier. The assignment focuses on a circuit containing this element and aims at providing an understanding of the properties of this amplifier circuit. The assignment is partly written, but also contains the actual building and testing of the circuit and also applying it for acoustic measurements.

D. Aircraft noise source modelling

For this assignment a program needs to be developed for calculating the noise levels for the various airframe components (clean wing, slat, flap, main landing gear).

E. Calculating noise footprints from Noise-Power-Distance tables

Current noise monitoring is based on models using the so-called Noise-Power-Distance (NPD) tables, specifying noise levels as a function of aircraft engine settings and distance. In the assignment such NPD table is used, together with an aircraft flight profile, to calculate the noise footprint for a certain aircraft.

F. Acoustic imaging

A series of assignments that focus on acoustic imaging, ranging from calculating the theoretical directivity of acoustic arrays, to imaging the noise from a real aircraft fly-over.

Out of all above assignments, A, B, C and F are required. A choice can be made between D and E.