Sökning: "turbulence structure"

Visar resultat 16 - 20 av 115 avhandlingar innehållade orden turbulence structure.

1. 16. On the modelling of turbulent flow and mixing in stirred reactors

   Författare :Johan Revstedt; Strömningsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; CFD; stirred reactors; impeller modelling; Energy research; mixing; LES; Energiforskning;

   Sammanfattning : This thesis concerns the numerical simulations and modelling of the flow structure and scalar transport in stirred reactors. For this Large Eddy Simulations (LES) have been used. The flow situation in a stirred reactor includes several flow phenomena that are not well predicted by "standard" two-equation models, e.g. LÄS MER

3. 17. Flow and Rheology of Pulp Suspensions at Medium Consistency

   Författare :Tomas Wikström; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fluidisation; yield stress; agitation; pulp suspension; computational fluid dynamics; fibre properties; turbulence; screening; Bingham model;

   Sammanfattning : Traditionally, development of pulp processing equipment has been based on the accumulation of qualitative knowledge (experience) with respect to the interaction of equipment and pulp suspensions. This way of developing equipment requires several trials and prototypes before the final product and process data can be established. LÄS MER

4. 18. Time-accurate Turbulence Modeling of Swirling Flow for Hydropower Application

   Författare :Ardalan Javadi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hybrid RANS-LES; Swirling Flow; DES; Vortex Breakdown; Turbulence Modeling; Hydropower; LES;

   Sammanfattning : Hydraulic turbomachines have played a prominent role in the procurement of renewableenergy for more than a century. Embedded in the context of general technological progress,their design for efficiency and reliability has reached an outstanding level of quality. LÄS MER

5. 19. Numerical studies of turbulent flames in wall-jet flows

   Författare :Zeinab Pouransari; Arne V. Johansson; Yves D'Angelo; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; combustion; direct numerical simulation; wall-jet; heat release effects; mixing scales; non-premixed flame; wall heat transfer; Teknisk mekanik; Engineering Mechanics;

   Sammanfattning : The present thesis deals with the fundamental aspects of turbulent mixing and non-premixed combustion in the wall-jet flow, which has a close resemblance to many industrial applications. Direct numerical simulations (DNS) of turbulent wall-jets with isothermal and exothermic reactions are performed. LÄS MER

7. 20. Simulations of Coastal Atmospheric Dynamics and Transport Processes

   Författare :Ragothaman Sundararajan; Dimitris Melas; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; coastal atmosphere; dynamics; transport; Lagrangian particle dispersion model; mesoscale model; turbulence; Geovetenskap; Earth sciences; Geovetenskap; Meteorology; meteorologi;

   Sammanfattning : The marine atmosphere can be highly variable in space and time, and the coastal terrain plays a crucial role in influencing its properties. These, in turn, determine the atmospheric transport in the coastal zone. LÄS MER