Sökning: "Fluid Flow"

Visar resultat 1 - 5 av 1348 avhandlingar innehållade orden Fluid Flow.

1. 1. Wings, turbulent boundary layers and flow separation

   Författare :Fermin Mallor; Philipp Schlatter; Ricardo Vinuesa; Ramis Örlü; Manuel García Villalba; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wings; turbulent boundary layers; adverse pressure gradients; flow separation; numerical simulations; wind-tunnel experiments; flow control.; Vingar; turbulenta gränsskikt; negativa tryckgradienter; avlösning; numeriska simuleringar; vindtunnel-experiment; flow control; Aerospace Engineering; Flyg- och rymdteknik; Teknisk mekanik; Engineering Mechanics;

   Sammanfattning : The present doctoral thesis investigates the turbulent flow developing around wing sections, focusing on the impact of adverse-pressure-gradient (APG) conditions on turbulent boundary layers (TBLs) and the physics of flow separation. Both experimental and numerical methods are employed to generate high-fidelity data sets and provide an in-depth analysis of the flow. LÄS MER

3. 2. Non-Spherical Particle Interaction in Duct and Jet Flow

   Författare :Ammar Hazim; Matthias Mandø; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Solid-gas flow; turbulence modulation; duct flow; coaxial jets flow; swirl jet flow; active flow control; synthetics jet; biomass powder; non-spherical particles; PIV measurement; Strömningslära; Fluid Mechanics;

   Sammanfattning : Wood waste is the most popular biomass recourse for many nations. Burned wood can, direct or indirect, release one of the greenhouse gases, carbon dioxide. The process can still be seen as a renewable source of energy since replanting of the trees and crops are consuming nearly the same amount of carbon dioxide through photosynthesis. LÄS MER

4. 3. Near wall fibre orientation in flowing suspensions

   Författare :Allan Carlsson; Daniel Söderberg; Fredrik Lundell; Helge I. Andersson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid mechanics; fibre orientation; shear flow; wall effect; fibre suspension; papermaking; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : This thesis deals with fibre orientation in wall-bounded shear flows. The primary application in mind is papermaking. The study is mainly experimental,but is complemented with theoretical considerations.The main part of the thesis concerns the orientation of slowly settlingfibres in a wall-bounded viscous shear flow. LÄS MER

5. 4. Turbulent Boundary Layer Separation and Control

   Författare :Ola Lögdberg; P. Henrik Alfredsson; Jens Fransson; Guido Buresti; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flow control; adverse pressure gradient APG ; flow separation; vortex generators; jet vortex generators; pulsed jet vortex generators; Fluid mechanics; Strömningsmekanik;

   Sammanfattning : Boundary layer separation is an unwanted phenomenon in most technical applications, as for instance on airplane wings, ground vehicles and in internal flow systems. If separation occurs, it causes loss of lift, higher drag and energy losses. It is thus essential to develop methods to eliminate or delay separation. LÄS MER

7. 5. Numerical investigation of the flow and instabilities at part-load and speed-no-load in an axial turbine

   Författare :Jelle Kranenbarg; Michel Cervantes; Lisa Prahl Wittberg; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Speed-no-load; vortical flow structures; flow instabilities; rotating stall; mitigation; independent guide vanes; axial turbine; swirling flow; off design operation; URANS; parametric study; blade clearance; head losses; diffusor; GEKO model; flow separation; hydraulic turbine; Strömningslära; Fluid Mechanics;

   Sammanfattning : Global renewable energy requirements rapidly increase with the transition to a fossil-free society. As a result, intermittent energy resources, such as wind- and solar power, have become increasingly popular. However, their energy production varies over time, both in the short- and long term. LÄS MER