Sökning: "boundary layer separation"

Visar resultat 1 - 5 av 12 uppsatser innehållade orden boundary layer separation.

1. 1. Testing aerosol vertical profiling methods with portable instruments on unmanned and manned aircraft

   Master-uppsats, Lunds universitet/Institutionen för naturgeografi och ekosystemvetenskap

   Författare :Ellen Grace Soroka; [2023]
   Nyckelord :Physical Geography; Ecosystem Analysis; Aerosols; Vertical Profile; Black Carbon; PM2.5; Nanoparticles; UAV; Drone; Master degree thesis; 30 credits in Atmospheric Science Biogeochemical Cycles; Earth and Environmental Sciences;

   Sammanfattning : This thesis employed several portable sensors on board an unmanned aerial vehicle (UAV) and manned aircraft in order to test new methods of measuring vertical profiles of aerosol particles and contribute to knowledge of aerosol distributions in the atmosphere. More data in this area is required to improve atmospheric modelling and future climate scenarios. LÄS MER

3. 2. Development of a CFD Boundary Condition to Simulate a Perforated Surface

   Uppsats för yrkesexamina på avancerad nivå, Umeå universitet/Institutionen för fysik

   Författare :Medet Kiflemariam; [2021]
   Nyckelord :Computational Fluid Dynamics; CFD; Boundary Condition; Bleed; Aerospace Engineering; Aeronautical Engineering; Physics;

   Sammanfattning : In aircraft with jet propulsion engine intakes at supersonic speed, strong pressure waves referred to as shockwaves occur, which may interact with any present boundary layers along the intake surface. The adverse pressure gradients associated with Shock Wave-Boundary Layer Interaction (SWBLI) may cause boundary layer flow separation, which can result in disturbances of the flow that can be harmful to the device or decrease engine performance. LÄS MER

4. 3. Development and validation of an improved wall-function boundary condition for computational aerodynamics

   Master-uppsats, KTH/Strömningsmekanik och Teknisk Akustik

   Författare :Carlo Loris Palombo; [2021]
   Nyckelord :Wall Functions; Wall Treatment; M-Edge; Computational Fluid Dynamics; Turbulent Boundary Layer; Turbulence Models; Väggfunktionsranvillkor; M-Edge; Strömningsmekaniska beräkningar; Turbulent Gränsskikt; Turbulensmodeller;

   Sammanfattning : Computational Fluid Dynamics is a powerful and widely used tool for developing projectsthat concern flow motion, in very different fields. Industrial CFD solvers are continuouslydeveloped with the aim of improving accuracy and reducing the computational cost of thesimulations. LÄS MER

5. 4. RANS & WMLES Simulations of Compressor Corner Separation

   Master-uppsats, KTH/Mekanik

   Författare :Arthur Poulain; [2019]
   Nyckelord :Corner Separation; Compressor Linear Cascade; RANS; Wall-Modeled LES; Boundary Layer; Anisotropy; Hörnseparation; Kompressor Linjär Kaskad; RANS; Vägg-Modell LES; Gränsskikt; Anisotropi;

   Sammanfattning : In axial compressor, corner separation phenomenon can occur between the blade surface and the hub. This leads to high total pressure losses, blockage and may worsen to surge. Various studies on NACA65-009 blade were previously performed experimentally and numerically to predict the corner separation. LÄS MER

7. 5. Enabling high-fidelity measurements of turbulent boundary layer flow over wing sections in the MTL wind tunnel.

   Master-uppsats, KTH/Mekanik

   Författare :Fermin Mallor; [2019]
   Nyckelord :Fluid mechanics; aerodynamics; turbulence; RANS; wind-tunnel experiments; insert design; Strömningsmekanik; aerodynamik; turbulens; RANS; vindtunnel experiment; inlaga designen;

   Sammanfattning : A reinforced fiber-glass model of a NACA 4412 wing profile is designed and set-up in the Minimum Turbulence Level (MTL) wind tunnel facility at KTH. The model has 65 pressure taps orifices, and the set-up includes two mounting panels designed to allow for particle image velocimetry (PIV) and hot wire anemometry (HWA) measurements of the boundary layer (to be performed in a future campaign). LÄS MER