Sökning: "Harmonic Balance Method"
Visar resultat 1 - 5 av 15 avhandlingar innehållade orden Harmonic Balance Method.
1. Acoustic source characterisation for non-linear in-duct sources
Sammanfattning : Different ways to model acoustic in-duct sources have beenanalysed. Measurements were conducted on two diesel truckengines. It was found that for steady state oscillations, onecould linearise in the neighbourhood of a given linearisationpoint, i.e. LÄS MER
2. Numerical Methods for Aeroacoustic Analysis of Turbomachines
Sammanfattning : Numerical simulations are important tools for developing new aircraft that can meet future needs. When numerical simulations are used to compute aircraft noise, a two-step procedure is often employed. In the first step, the noise sources are determined using, e.g. LÄS MER
3. Numerical Methods for Aeroacoustic Analysis of Turbomachinery
Sammanfattning : Air transportation is today an integral part of many peoples life and it continuously grow to serve more of us in new and ingenious ways. There are however negative sides to this growth as well, such as increased noise around airports and more CO2 emissions, which must be addressed if aviation is to be part of a sustainable future. LÄS MER
4. Control and Analysis of Pulse-Modulated Systems
Sammanfattning : The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. LÄS MER
5. Turbomachinery Aeroacoustic Calculations using Nonlinear Methods
Sammanfattning : Noise regulations for aircraft that fly over populated areas are becoming continuously stricter. This in combination with increasing computational capabilities has boosted interest in aeroacoustic computations in the aerospace industry. LÄS MER