Search for dissertations about: "Embedded Boundary methods"

Showing result 1 - 5 of 8 swedish dissertations containing the words Embedded Boundary methods.

2. 1. Compressible Turbulent Flows : LES and Embedded Boundary Methods

   Author : Marco Kupiainen; Bjorn Engquist; William Henshaw; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; Embedded Boundary methods; Compressible flow; turbulent flow; Numerical analysis; Numerisk analys; Computational physics; Beräkningsfysik; Fluid mechanics; Strömningsmekanik;

   Abstract : .... READ MORE

4. 2. Assessment and Some Improvements of Hybrid RANS-LES Methods

   Author : Sebastian Arvidson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; hybrid RANS-LES; zonal RANS-LES; embedded LES; PDH-LRN; log-layer mismatch; LES length scale; shock boundary-layer interaction;

   Abstract : Motivated by numerical analysis of a shock/boundary-layer interacting (SBLI) flow in a duct, where some typical existing hybrid RANS-LES methods become awkward to give accurate predictions of the shock-induced corner separation bubble, a new hybrid RANS-LES method, has been proposed. The model is based on a low-Reynolds-number (LRN) $k-\omega$ RANS model, which is one of the few models that are capable of giving reasonable predictions for the SBLI flow in RANS computations. READ MORE

5. 3. Construction of Adaptive Multistep Methods for Problems with Discontinuities, Invariants, and Constraints

   Author : Fatemeh Mohammadi; Numerisk analys; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; multistep methods; Initialization; beta-blocking; Discontinuity; Time adaptivity; Strong stability preserving; Differential algebraic equations;

   Abstract : Adaptive multistep methods have been widely used to solve initial value problems. These ordinary differential equations (ODEs) may arise from semi-discretization of time-dependent partial differential equations(PDEs) or may combine with some algebraic equations to represent a differential algebraic equations (DAEs). READ MORE

6. 4. Methodologies for RANS-LES interfaces in turbulence-resolving simulations

   Author : Sebastian Arvidson; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE

7. 5. Efficient Simulation of Wave Phenomena

   Author : Martin Almquist; Ken Mattsson; Gianluca Iaccarino; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; finite difference method; high-order accuracy; stability; summation by parts; simultaneous approximation term; quantum mechanics; Dirac equation; local time-stepping; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

   Abstract : Wave phenomena appear in many fields of science such as acoustics, geophysics, and quantum mechanics. They can often be described by partial differential equations (PDEs). As PDEs typically are too difficult to solve by hand, the only option is to compute approximate solutions by implementing numerical methods on computers. READ MORE