Sökning: "time-domain methods"

Visar resultat 1 - 5 av 172 avhandlingar innehållade orden time-domain methods.

1. 1. Time-Domain Methods for the Maxwell Equations

   Författare :Ulf Andersson; KTH; []
   Nyckelord :Computational Electromagnetics; time-domain methods;

   Sammanfattning : .... LÄS MER

3. 2. Time Domain Boundary Element Methods for Acoustic Scattering

   Författare :Georgios Natsiopoulos; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time domain; curved surface; room acoustics; boss model; boundary element method; regularization; transient; Hermite interpolation; hypersingular; acoustic scattering; vector potential;

   Sammanfattning : In room acoustics, numerical computation of scattering phenomena is an important subject, since it is needed to accurately predict the influence of reflectors, the audience, balconies, etc, on the perceived acoustic quality of auditoria. The large physical volumes of auditoria and the wide frequency content of music and speech, together with the complicated geometries involved however, makes predictions in room acoustics a challenging task from a computational point of view. LÄS MER

4. 3. Hybrid Solvers for the Maxwell Equations in Time-Domain

   Författare :Fredrik Edelvik; Per Lötstedt; Jan Hesthaven; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Maxwell s equations; time-domain; finite volume methods; finite element methods; hybrid solver; dispersive materials; thin wires; Beräkningsvetenskap; Scientific Computing;

   Sammanfattning : The most commonly used method for the time-domain Maxwell equations is the Finite-Difference Time-Domain method (FDTD). This is an explicit, second-order accurate method, which is used on a staggered Cartesian grid. The main drawback with the FDTD method is its inability to accurately model curved objects and small geometrical features. LÄS MER

5. 4. Time Domain Methods for Load Identification of Linear and Nonlinear Systems

   Författare :Patrik Nordberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; inverse problem; ill-conditioning; upper block triangular Toeplitz matrix; regularization; wavelet parameterization; least squares problem; input estimation; time domain; linear and nonlinear systems; load identification;

   Sammanfattning : The automotive industry faces an increasing demand for virtual prototyping to simulate the operation conditions of vehicles and subsystems. Each component, as well as the complete vehicle, must meet the desired design requirements in a time- and cost-efficient development process. LÄS MER

7. 5. Efficient time-domain modelling suitable for optimising thermoacoustic devices

   Författare :Stig Kleiven; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; finite-difference; thermoacoustics; time domain; optimisation; equivalent source method; active control;

   Sammanfattning : Thermoacoustic heat pumps use acoustic work to transfer heat from cold to hot temperatures. Such devices benefit from being environmentally friendly, robust and simple. However, in practice these devices have too low efficiency and power compared to their conventional counterparts. LÄS MER