Sökning: "transonic flow"

Visar resultat 6 - 10 av 36 avhandlingar innehållade orden transonic flow.

  1. 6. Numerical Computations of Internal Combustion Engine related Transonic and Unsteady Flows

    Författare :Olle Bodin; Laszlo Fuchs; Daniel Lörstad; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; Transonic flow; Hysteresis; Shock boundary-layer interaction; Exhaust valve; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Vehicles with internal combustion (IC) engines fueled by hydrocarbon compounds have been used for more than 100 years for ground transportation. During the years and in particular in the last decade, the environmental aspects of IC engines have become a major political and research topic. LÄS MER

  3. 7. Modal Decomposition of Separated Nozzle Flow

    Författare :Ragnar Larusson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Arnoldi; axisymmetric convergent-divergent nozzle; Mode Decomposision; Flow Separation; Resonance.; Dynamic Mode Decomposision; Computational Fluid Dynamics;

    Sammanfattning : The applicability of two different eigenvalue algorithms coupled with an axisymmetric RANS solver to predict the eigenmodes of separated supersonic flow inside an axisymmetric convergent-divergent nozzle was investigated. These are the Arnoldi and the Dynamic Mode Decomposition (DMD) algorithms, respectively. LÄS MER

  4. 8. On Multistage Analysis of Transonic Compressors: From Axisymmetric Throughflow Time-Marching to Unsteady Three-Dimensional Methods

    Författare :Stephane Baralon; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; shock; time-marching; deterministic; average-passage; multistage; fan; axisymmetric; 3D; unsteady; transonic; viscous; body force; stress; singularity; perturbation; throughflow; mixing-plane; modelling; finite-volume;

    Sammanfattning : A throughflow time-marching finite-volume solver, capable of computing viscous transonic multistage compressor flows with embedded shocks, is presented. The behavior of the blade model, based on the blade mean surface flow tangency condition, was investigated for transonic flows. LÄS MER

  5. 9. Experimental Investigation of Velocity Gust in High Pressure Turbines

    Författare :Kai Freudenreich; KTH; []
    Nyckelord :turbomachinery; unsteady aerodynamics; gust; forcing function; forced response; transonic flow; annular cascade; Laser-Two-Focus Anemometer; experiments;

    Sammanfattning : This thesis investigates the unsteady three-dimensional gustfield in high subsonic and transonic turbine stages based onexperimental velocity data. The generation, propagation andinteraction mechanisms of the velocity gust in high pressureturbines are studied. LÄS MER

  7. 10. Numerical methods for load and response prediction for use in acoustic fatigue

    Författare :Johan Nilsson; Byggnadsmekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustic fatigue; Sonic fatigue; Computational Fluid Dynamics; Large Eddy Simulation; Finite Element Method; Random response analysis; Separated flow; High Re; Backward-facing step; Fence flow; Aircraft; Proper Orthogonal Decomposition; Acoustic fatigue; Sonic fatigue; Computational Fluid Dynamics; Large Eddy Simulation; Finite Element Method; Random response analysis; Separated flow; High Re; Backward-facing step; Fence flow; Aircraft; Proper Orthogonal Decomposition;

    Sammanfattning : Acoustic fatigue can occur in structural elements of an aircraft exposed to very high sound pressures. To deal with acoustic fatigue, mainly empirical methods have been applied and often late in the design phase. Current design guidelines have three main limitations. First, they do not say anything about the load intensities. LÄS MER