Sökning: "Detached Eddy Simulation"

Visar resultat 1 - 5 av 20 avhandlingar innehållade orden Detached Eddy Simulation.

1. 1. Detached Eddy Simulation for Aerospace Applications

   Författare :Gonzalo Montero Villar; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Evolutionary algorithms; Synthetic turbulence; Chorochronic; POD based phase-lag; Sliding grid; Nozzle flow separation; Hybrid RANS LES; Phase-lagged boundary conditions; Stochastic optimization; CFD; LODI;

   Sammanfattning : With the continuous growth in air traffic that we see nowadays, comes an increase in the requirements needed to be satisfied in order to certify an aircraft for operation. These stricter regulations affect aspects such as CO2 emissions, sound pollution and so on, pushing manufacturers to aim for lighter, more efficient, more robust designs. LÄS MER

3. 2. Large eddy simulation of cavitating and non-cavitating flow

   Författare :Tobias Huuva; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high Reynolds number; Cavitation; turbulence; RANS; hydrodynamics; numerical simulation; modelling; DES; LES;

   Sammanfattning : Most marine configurations are subject to a number of complex and important hydrodynamic phenomena affecting the overall performance of the vessel, both regarding resistance and propulsive efficiency. In this thesis, the possibility of numerically simulating some of these phenomena is investigated. LÄS MER

4. 3. Investigation of Tonal Noise Sources from Centrifugal Fan using Detached Eddy Simulation

   Författare :Martin Ottersten; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Computational aeroacoustics; Blade passing frequency; Centrifugal fan; Low-frequency rotation; Tonal noise.;

   Sammanfattning : Since we spend the majority of our time indoors, heating, ventilation, and air conditioning (HVAC) systems have become a more and more important part of many people´s life. They provide a sufficient amount of airflow with the correct temperature, quality, and humidity. LÄS MER

5. 4. Numerical Simulation of High Reynolds Number Wall Bounded Flow

   Författare :Tobias Persson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; subgrid model; DES; high; validation; LES; numerical simulation; near-wall;

   Sammanfattning : In this thesis, four different numerical methods are used for predictions of high Reynoldsnumber (Re), wall bounded flows; Large Eddy Simulation (LES) with two different subgrid(turbulence) models, the One Equation Eddy Viscosity model (OEEVM) and the MixedModel (MM), Monotone Integrated LES (MILES), Detached Eddy Simulation (DES) andReynolds Averaged Navier Stokes (RANS). The LES calculations are combined with a wallmodel based on the law-of-the-wall and in DES a hybrid RANS/LES method is used forhandling the near wall region. LÄS MER

7. 5. Numerical and modelling aspects of large-eddy and hybrid simulations of turbulent flows

   Författare :Matteo Montecchia; Arne V. Johansson; Gert Brethouwer; Stefan Wallin; Dominic Von Terzi; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; wall-bounded flows; large-eddy simulation; SGS modelling; OpenFOAM; hybrid RANS-LES; Engineering Mechanics; Teknisk mekanik;

   Sammanfattning : In this study, the explicit algebraic sub-grid scale (SGS) model (EAM) has been extensively validated in wall-resolved large-eddy simulations (LES) of wall-bounded turbulent flows at different Reynolds numbers and a wide range of resolutions. Compared to eddy-viscosity based models, the formulation of the EAM is more consistent with the physics and allows to accurately capture SGS anisotropy,which is relevant especially close to walls. LÄS MER