NPTEL Courses

Acoustic Instabilities in Aerospace Propulsion

Introduction to acoustics and combustion driven oscillations. Derivation of the wave equation. Traveling wave solutions. Acoustic energy corollary. Impedance and admittance. Standing wave solutions. Reflection and transmission. Impedance tube technique. Effect of area and temperature variation on wave propagation. Wave equation in cylindrical coordinates and its applications. Basic principles of combustion driven oscillations. Rayleigh criteria. Mechanisms for instability in solid and liquid rockets, ramjets, gas turbines. Pulse combustors and their analysis using Galerkin technique. Modal analysis. Nonmodal stability analysis. Passive and active control of combustion instability. (from nptel.ac.in )


Prof. R. I. Sujith, Department of Aerospace Engineering, IIT Madras.
Aeronautics and astronautics

Record ID


Lecture 01 - Introduction to Thermoacoustic Instabilities