Sökning: "wave equation"

Visar resultat 16 - 20 av 96 uppsatser innehållade orden wave equation.

1. 16. Computation of Acoustic Wave Propagation Under Water

   Master-uppsats, KTH/Matematik (Avd.)

   Författare :Frida Thörn; [2022]
   Nyckelord :Wave equation; Helmholtz equation; Waveholtz iteration; finite difference method; summation by parts; energy method; point source; curvilinear coordinates; vågekvationen; helmholtz ekvation; waveholtz iteration; finita differens methoden; energimetoden; punktkälla; kurvlinjära koordinater; kroklinjiga koordinater; SBP;

   Sammanfattning : In this thesis we look at acoustic wave propagation under water. We look in particular at waves generated by a point source and what happens with the propagation when we model the bottom as flat or as curvilinear. We assume the source to be working at a certain frequency and therefore we model this problem by solving the Helmholtz equation. LÄS MER

3. 17. Finite Difference Approximations for Wave Propagation

   Kandidat-uppsats, Linköpings universitet/Tillämpad matematik; Linköpings universitet/Tekniska fakulteten

   Författare :Sebastian Lindqvist; [2022]
   Nyckelord :Finite Difference; Maxwell’s equations; wave propagation; advection equation; partial differential equations;

   Sammanfattning : Finite difference approximations are methods for solving differential equations by approximating derivatives. This work will begin with how to solve a partial differential equation (PDE) called the advection equation, ut + cux = 0. LÄS MER

4. 18. A unified view of a family of soliton equations related to spin Calogero-Moser systems

   Master-uppsats, KTH/Fysik

   Författare :Anton Ottosson; [2022]
   Nyckelord :Soliton equations; Solitons; Integrable systems; Spin Calogero-Moser systems; Exact solutions; Benjamin-Ono-type equations; Solitonekvationer; Solitoner; Integrerbara system; sCM-system; Exakta lösningar; Ekvationer av Benjamin-Ono-typ;

   Sammanfattning : We study the interconnections between the spin Benjamin-Ono (sBO) and half-wave maps (HWM) equations, a pair of nonlinear partial integro-differential equations that have recently been found to permit multi-soliton solutions, where the time evolution of the constituent solitons can be described in terms of the well-known, completely integrable, spin Calogero-Moser (sCM) system. By considering a symmetry transformation of the sCM dynamics we are led to introduce a scale parameter into the sBO equation, yielding what we call the rescaled sBO (rsBO) equation, which has both the sBO and HWM equations as special cases. LÄS MER

5. 19. Modeling of optical microresonator frequency combs

   Uppsats för yrkesexamina på avancerad nivå, Linköpings universitet/Institutionen för fysik, kemi och biologi

   Författare :Michael Ekström; [2022]
   Nyckelord :Optical frequency combs; Nonlinear optics; Temporal cavity solitons;

   Sammanfattning : An optical frequency comb is a structure of equidistant, coherent spectral components which can be thought of as a large array of individual phase-locked laser sources. Their utilization in precision spectroscopy garnering part of the 2005 Nobel prize, optical frequency combs constitute a relatively novel technology with a large number of potential and actual applications. LÄS MER

7. 20. Numerical simulation of acoustic wave propagation with a focus on modeling sediment layers and large domains

   Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Avdelningen för beräkningsvetenskap

   Författare :Elias Estensen; [2022]
   Nyckelord :Helmholtz; wave equation; acoustics; ocean acoustics; numerical analysis; computational science; finite differences; summation by parts; sbp; waveholtz; cylindrical coordinates; sediment layers; interface; super-grid; super grid; absorbing layer; Helmholtz; vågekvationen; akustik; undervattensakustik; numerisk analys; beräkningsvetenskap; finita differenser; summation by parts; sbp; cylindriska koordinater; waveholtz; sedimentskikt; interface; super-grid; absorberande lager;

   Sammanfattning : In this report, we study how finite differences can be used to simulate acoustic wave propagation originating from a point source in the ocean using the Helmholtz equation. How to model sediment layers and the vast size of the ocean is studied in particular. LÄS MER