Search for dissertations about: "allmaras"

Found 5 swedish dissertations containing the word allmaras.

2. 1. Integrated Duct Aerodynamics

   Author : Elias Siggeirsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DDES; RANS; CFD; Compressor duct; Spalart-Allmaras;

   Abstract : Air traffic is rapidly increasing, with no sign of slowing down, resulting in increased green-house gases emission. With emission criteria becoming stricter every year, the aircraft design is subjected to continuous improvements. The development of more efficient aircraft engines plays a central role in the strive towards lower emission levels. READ MORE

4. 2. Turbine Outlet Guide Vane Flows

   Author : Johan Hjärne; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Spalart-Allmaras model; k-ω SST model; linear cascade; secondary flows; turbine exhaust casing; RSM; k-ε realizable model; turbine rear frame; engine mount bump; tail bearing housing; Outlet guide vane;

   Abstract : New design goals on modern jet engines often leads to more highly loaded turbines with fewer stages in order to save weight and cost. This gives higher swirl angles into the outlet guide vane (OGV), implying a more difficult aerodynamic design. READ MORE

5. 3. Aspects of the recursive projection method applied to flow calculations

   Author : Joakim Möller; Jesper Oppelstrup; Per Weinerfelt; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Datorteknik; applied mechanics; computer science; aerospace; Datorteknik; Computer engineering; Datorteknik;

   Abstract : In this thesis, we have investigated the Recursive Projection Method, RPM, as an accelerator for computations of both steady and unsteady flows, and as a stabilizer in a bifurcation analysis.The criterion of basis extraction is discussed. READ MORE

6. 4. Analysis of the Unsteady Flow Field of a Passenger Vehicle

   Author : Lennert Sterken; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind tunnel; Wake; CFD; Pressure measurements; Extensions; Yaw response; External aerodynamics; Aerodynamic forces;

   Abstract : Political legislation and consumer requirements for a sustainable society require that vehicle manufacturers focus on reduced fuel consumption and lower emissions. Areduction in the overall energy consumption can be directly linked to a decrease of the driving resistance, where the aerodynamic drag significantly contributes at velocities above 70km/h. READ MORE

7. 5. Numerical Simulation of Some Heat Transfer and Fluid Flow Phenomena for Gas Turbine Blades and a Transonic Turbine Stage

   Author : Fadil Mumic; Värmeöverföring; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluiddynamik; plasma; Thermal engineering; applied thermodynamics; plasmas; Gaser; fluid dynamics; Gases; transonic; numerical; heat transfer coefficient; shroud surface; squealer blade tip; flat blade tip; leakage flow; Termisk teknik; termodynamik; turbulence modeling;

   Abstract : With the attempts to achieve higher thermal efficiency, turbine blades are exposed to very high temperature gases and may undergo severe thermal stress and fatigue. Thus, in order to develop optimal cooling strategies and reduce the heat transfer it is important to obtain a good understanding of both the complex flow field and the heat transfer characteristics in turbine rotor/stator hot-gas passages. READ MORE