Sökning: "RANS simulations"

Visar resultat 1 - 5 av 73 avhandlingar innehållade orden RANS simulations.

  1. 1. Methodologies for RANS-LES interfaces in turbulence-resolving simulations

    Författare :Sebastian Arvidson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; zonal RANS-LES; aeronautics; RANS-LES interfaces; Hybrid RANS-LES; grey-area mitigation; log-layer mismatch; embedded LES; LES length scale; LES;

    Sammanfattning : Hybrid Reynolds-Average Navier-Stokes (RANS)-Large-Eddy Simulations (LES) techniques are now seen by the aeronautical industry as the most promising turbulence-resolving approaches for complex high-Reynolds-number turbulent flows with regard to cost and accuracy. However, connecting RANS and LES simulated flows is a challenging task and needs special attention in order to increase simulation robustness and accuracy. LÄS MER

  3. 2. Mooring dynamics for wave energy applications

    Författare :Johannes Palm; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hp adaptivity; Wave energy; Coupled simulations; CFD; Discontinuous Galerkin methods; OpenFOAM; Mooring dynamics; Snap loads; RANS;

    Sammanfattning : This work aims to increase the modelling accuracy of two important problems for the wave energy industry. One concerns the mooring dynamics in the presence of snap loads (shock waves in cable tension). The other is related to nonlinear effects in the resonance region of moored wave energy converters (WECs). LÄS MER

  4. 3. Optimization of Chemical Kinetic Mechanisms and Numerical Simulations of Industrial Gas Turbine Burners

    Författare :Abdallah Abou-Taouk; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SAS-SST; LES; Gas Turbine Combustion; Swirling Flow; Global Mechanism; Finite Rate Chemistry; Partially Premixed Flames; Chemistry Reduction; RANS;

    Sammanfattning : Increasing demands on environmentally friendly energy conversion indicate that pollutants need to be reduced. Computational Fluid Dynamics is efficiently used today in turbulent reaction flow simulations to gain a deeper understanding of the combustion process and consequently be able to improve combustor design and reduce emissions. LÄS MER

  5. 4. Turbulence-resolving simulations for engineering applications

    Författare :Bastian Nebenführ; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; Aeroacoustics; Forest canopy; Airframe noise; hybrid RANS LES; Turbulence-resolving simulation; Wind-turbine fatigue loads; Wind power;

    Sammanfattning : Most fluid flows of industrial interest are turbulent and their accurate representation may be of vital importance for the design process of new products. To date, steady RANS methods are usually employed for the simulation of turbulent flows of everyday engineering problems. LÄS MER

  7. 5. Efficient Full-Scale CFD for Ship Hydrodynamics

    Författare :Michal Orych; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; CFD; Self-propulsion; Ship; Verification; Uncertainty; Full-scale; Validation; Seakeeping; Energy-Saving Device; Roughness; RANS;

    Sammanfattning : An efficient numerical approach for ship hydrodynamics, involving a hybrid free-surface potential flow/RANS method, is explored. The work focuses on estimating the delivered power of ships in calm water and in waves, highlighting the benefits of full-scale simulations, particularly for ships with Energy Saving Devices. LÄS MER