Sökning: "Secondary flow"

Visar resultat 16 - 20 av 268 avhandlingar innehållade orden Secondary flow.

1. 16. Experimental study of the rotating-disk boundary-layer flow

   Författare :Shintaro Imayama; Henrik Alfredsson; Rebecca Lingwood; Benoît Pier; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; boundary layer; rotating disk; laminar-turbulent transition; convective instability; absolute instability; secondary instability; crossflow instability; hot-wire anemometry.;

   Sammanfattning : Rotating-disk flow has been investigated not only as a simple model of cross flow instability to compare with swept-wing flow but also for industrial flow applications with rotating configurations. However the exact nature of laminar-turbulent transi- tion on the rotating-disk flow is still major problem and further research is required for it to be fully understood, in particular, the laminar-turbulent transition process with absolute instability. LÄS MER

3. 17. Aerodynamic Investigation of Leading Edge Contouring and External Cooling on a Transonic Turbine Vane

   Författare :Ranjan Saha; Torsten Fransson; Jens Fridh; Tony Arts; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gas turbine; aerodynamics; secondary flow; external cooling; trailing edge cooling; film cooling; aerodynamic loss; high pressure turbine; nozzle guide vane; Aerospace Engineering; Flyg- och rymdteknik; Energiteknik; Energy Technology;

   Sammanfattning : Efficiency improvement in turbomachines is an important aspect in reducing the use of fossil-based fuel and thereby reducing carbon dioxide emissions in order to achieve a sustainable future. Gas turbines are mainly fossil-based turbomachines powering aviation and land-based power plants. LÄS MER

4. 18. Thermal and Hydraulic Performance of Enhanced Rectangular Tubes for Compact Heat Exchangers

   Författare :Carl-Olof Olsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; LDV; heat exchanger; enhanced heat transfer; radiator; smoke visualization; pressure drop; secondary flow;

   Sammanfattning : The thermal and hydraulic performance of rib-roughened, dimpled and offset strip fin tubes has been investigated experimentally. Results from measurements on commercially manufactured tubes have shown that rib-roughened tubes have best potential for heat transfer enhancement with moderate pressure drop increase. LÄS MER

5. 19. Turbulence Transport Modelling in Gas Turbine Related Applications

   Författare :Andreas Sveningsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; RANS; secondary flow; realizability; V2F; transition;

   Sammanfattning : Computational fluid dynamics is a cornerstone in gas turbine engine design. It is used to optimize shapes of turbine and compressor airfoils, to predict heat transfer to gas turbine hot parts, to reduce the amount of pollutants that form when fuel is burnt, to reduce gas turbine noise and so on. LÄS MER

7. 20. Numerical Studies of Mixing in Pipes and Static Mixers

   Författare :Mårten Regner; Livsmedelsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent mixing; Secondary flow; Viscosity ratio; Computational fluid dynamics; Food and drink technology; Livsmedelsteknik; Rate of striation thinning; Static mixer; Laminar mixing;

   Sammanfattning : The objective of the present work was to investigate the mixing process in static mixers under laminar flow conditions, and in pipes during the displacement of dissimilar liquids. A numerical scheme and a method of characterizing static mixers were developed. LÄS MER