Sökning: "Time domain solutions"

Visar resultat 1 - 5 av 173 avhandlingar innehållade orden Time domain solutions.

  1. 1. 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

  3. 2. 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

  4. 3. Time-domain modelling of high-frequency wheel/rail interaction

    Författare :Astrid Pieringer; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wheel rail interaction; railway noise; roughness; time domain; frictional instability; discrete irregularities; transient contact; non-Hertzian contact;

    Sammanfattning : The interaction between wheel and rail is the predominant source of noise emission from railway operations in a wide range of conventional speeds. On the one hand, this wheel/rail noise concerns rolling noise and impact noise caused by the vertical interaction excited by roughness and discrete irregularities of the wheel/rail running surfaces, respectively. LÄS MER

  5. 4. Partitioned methods for time-dependent thermal fluid-structure interaction

    Författare :Azahar Monge; Numerisk analys; []
    Nyckelord :thermal FSI; Conjugate heat transfer; Domain decomposition; Time adaptivity; Coupled problems; multirate;

    Sammanfattning : The efficient simulation of thermal interaction between fluids and structures is crucial in the design of many industrial products, e.g. turbine blades or rocket nozzles. LÄS MER

  7. 5. Fully Printed Chipless RFID Tags towards Item-Level Tracking Applications

    Författare :Botao Shao; Lirong Zheng; Smail Tedjini; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Chipless RFID tag; configurability; inkjet printing; time domain; frequency domain; paper substrate; tag antenna; linearly tapering; LC resonator;

    Sammanfattning : An ID generating circuit is unquestionably the core of a chipless RFID tag. For convenience of printing process and cost consideration, the circuit should be kept as simple as possible. LÄS MER