Sökning: "Acoustic Coupling"

Visar resultat 1 - 5 av 59 avhandlingar innehållade orden Acoustic Coupling.

1. 1. Computational Aeroacoustics Based on Large Eddy Simulation and Acoustic Analogies

   Författare :Mihai Mihaescu; Laszlo Fuchs; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Mechanical engineering; hydraulics; plasma; Technological sciences; Teknik; fluiddynamik; plasmas; Gaser; fluid dynamics; Gases; Inhomogeneous Wave Equation; Acoustic Boundary Conditions; Acoustic Source Terms; LES; Computational Aeroacoustics; Turbulent Flows; vacuum technology; vibration and acoustic engineering; Maskinteknik; hydraulik; vakuumteknik; vibrationer; akustik; Computational Aeroacoustics;

   Sammanfattning : The thesis presents a numerical method developed by the author and its applications for computing the generated sound by an unsteady flow field and its propagation. The full equations of motion for compressible and unsteady flows describe both flow field and sound generation and propagation. LÄS MER

3. 2. Numerical Simulations of Turbulent Flows at Widely Different Mach Numbers

   Författare :Dragos Moroianu; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vibration and acoustic engineering; Maskinteknik; hydraulics; vacuum technology; Mechanical engineering; plasma; Energy research; Energiforskning; fluiddynamik; plasmas; Gaser; fluid dynamics; Gases; computational fluid dynamics; Acoustic; hydraulik; vakuumteknik; vibrationer; akustik; compressible flow;

   Sammanfattning : The present thesis mainly focuses on the numerical simulation of the turbulent flow field and acoustics developed in different industrial applications. The study covers a large range of Mach numbers, starting from incompressible regimes and ending with a fully compressible flow. LÄS MER

4. 3. Acoustic scattering in ducts and influence of flow coupling

   Författare :Susann Boij; KTH; []
   Nyckelord :sound; vortex sheet; flow separation; end correction; Strouhal number; non-orthogonal modes; energy balance; TECHNOLOGY; TEKNIKVETENSKAP;

   Sammanfattning : The subject of this thesis is the acoustic properties offlow duct area expansions and the influence of flow-acousticcoupling at sharp edges. For low Mach number flow, significantinteraction between the sound field and the flow field canoccur at such points of flow separation. LÄS MER

5. 4. Acoustic source characterisation for non-linear in-duct sources

   Författare :Fredrik Albertson; KTH; []
   Nyckelord :in-duct source; source characterisation; non-linear source; linearity test; hybrid method; IC-engine; muffler; coupling method;

   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

7. 5. Finite Element Procedures for Fluid-structure Interaction

   Författare :Joakim Hermansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nitsche s method; stabilized Crouzeix-Raviart; Winslow s method; Raviart-Thomas; space-time FE; stretched elements; FSI; FEM; weak coupling; mesh smoothing; acoustic FSI; ALE;

   Sammanfattning : This thesis concerns finite element (FE) methods for solving fluid-structure interaction (FSI) problems. Two types of fluid-structure interaction are considered. A finite element method for solving the interaction between a flowing incompressible fluid and a linear elastic structure is proposed. The flow is assumed to be laminar. LÄS MER