Search for dissertations about: "unsteady CFD"

Showing result 1 - 5 of 60 swedish dissertations containing the words unsteady CFD.

2. 1. Realistic simulations of delta wing aerodynamics using novel CFD methods

   Author : Stefan Görtz; Arthur Rizzi; Miguel Visbal; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Space and plasma physics; CFD; aerodynamics; flow physics; steady; unsteady; delta wing; vortical flow; Rymd- och plasmafysik; Space physics; Rymdfysik;

   Abstract : The overall goal of the research presented in this thesis is to extend the physical understanding of the unsteady external aerodynamics associated with highly maneuverable delta-wing aircraft by using and developing novel, more efficient computational fluid dynamics (CFD) tools. More specific, the main purpose is to simulate and better understand the basic fluid phenomena, such as vortex breakdown, that limit the performance of delta-wing aircraft. READ MORE

4. 2. Accurate physical and numerical modeling of complex vortex phenomena over delta wings

   Author : Simone Crippa; Arthur Rizzi; Stefan Wallin; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; computational fluid dynamics; CFD; vortical flow; delta wing; aerodynamics; flow physics; steady; unsteady; Vehicle engineering; Farkostteknik;

   Abstract : With this contribution to the AVT-113/VFE-2 task group it was possible to prove the feasibility of high Reynolds number CFD computations to resolve and thus better understand the peculiar dual vortex system encountered on the VFE-2 blunt leading edge delta wing. Initial investigations into this phenomenon seemed to undermine the hypothesis, that the formation of the inner vortex system relies on the laminar state of the boundary layer at separation onset. READ MORE

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

   Author : Michal Orych; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE

6. 4. Design, Optimization and Evaluation of a Transonic Aeroelastic Rig

   Author : Simeng Tian; Andrew R. Martin; Mauricio Gutierrez Salas; Dieter Peitsch; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transonic compressor; Aeroelastic rig; Design; CFD; Unsteady flow; Energiteknik; Energy Technology;

   Abstract : The compressor is one of the most essential components of a modern turbomachinery engine. This component is exposed to vibrations that without proper design can damage structural integrity and lead to failure. READ MORE

7. 5. Numerical Investigation of Aerodynamic Blade Excitation Mechanisms in Transonic Turbine Stages

   Author : Björn Laumert; KTH; []
   Keywords : Transonic Turbines; CFD; Forced Response; Unsteady Aerodynamics;

   Abstract : With the present drive in turbomachine engine developmenttowards thinner and lighter bladings, closer spaced blade rowsand higher aerodynamic loads per blade row and blade, advanceddesign criteria and accurate prediction methods for vibrationalproblems such as forced response become increasingly importantin order to be able to address and avoid fatigue failures ofthe machine early in the design process. The present worksupports both the search for applicable design criteria and thedevelopment of advanced prediction methods for forced responsein transonic turbine stages. READ MORE