Sökning: "bluff body flows"

Visar resultat 1 - 5 av 14 avhandlingar innehållade orden bluff body flows.

  1. 1. Under-body and Diffuser Flows of Passenger Vehicles

    Författare :Ture Jesper Marklund; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Bluff bodies; Vehicle aerodynamics; CFD; Wake flow; Boundary layer;

    Sammanfattning : Energy efficient vehicles will be required to meet future emission and fuel consumption requirements. Customers require reduced fuel consumption due to increasing fuel prices and the environmental issues, are drivers to reduce CO2. LÄS MER

  3. 2. Dynamics of Exhaust Valve Flows and Confined Bluff Body Vortex Shedding

    Författare :Marcus Winroth; P. Henrik Alfredsson; Knud Erik Meyer; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : This thesis can be divided into two interconnected topics; engine exhaust-valve flows and confined bluff-body vortex shedding. When optimising engine flow systems it is common to use low order simulation tools that require empirical inputs, for instance with respect to flow losses across the exhaust valves. LÄS MER

  4. 3. Experimental design and vortex analyses in turbulent wake flows

    Författare :Bengt E. G. Fallenius; Jens H. M. Fransson; Henrik Alfredsson; Marianna Braza; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bluff bodies; wake flow; experimental design; vortex detection; flow control; asymptotic suction boundary layer;

    Sammanfattning : A new experimental setup for studies on wake flow instability and its control that successfully has been designed and manufactured, is introduced and de- scribed. The main body is a dual-sided flat plate with an elliptic leading edge and a blunt trailing edge. LÄS MER

  5. 4. Active Flow Control for Aircrafts and Heavy Vehicles

    Författare :Mohammad El-Alti; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Trucks; Drag reduction; Bluff-body; Large-eddy Simulation; Wake; Tilt-rotor wing; optimization; Aircrafts; Heavy vehicles; Active and Passive Flow Control; Response surface methodology; Synthetic-jet Actuator;

    Sammanfattning : Bluff-body flows are dominated by large dissipative vortex-shedding wakes with low mean pressure compared to the high pressure on their frontal area. This induced pressure difference is the major contribution to the total aerodynamic drag. LÄS MER

  7. 5. Active Flow Control for Drag Reduction of Heavy Vehicles

    Författare :Mohammad El-Alti; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Active and Passive Flow Control; Tilt-rotor wing; Large-eddySimulation; Heavy vehicles; optimization; Full-scale road test; Trucks; Bluff-body; Wake; Drag reduction; Aircrafts; Response surface methodology; Synthetic-jet Actuator;

    Sammanfattning : This thesis considers the aerodynamics of trucks. The work focuses on the aerodynamic drag caused by the wake. Bluff-body flows are dominated by large dissipative vortex-shedding wakes with a low mean pressure compared to the high pressure on their frontal area. LÄS MER