Search for dissertations about: "drag force"

Showing result 1 - 5 of 74 swedish dissertations containing the words drag force.

2. 1. Drag reduction using plasma actuators

   Author : Romain Futrzynski; Gunilla Efraimsson; P. Henrik Alfredsson; Charles Mockett; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flow control; drag reduction; plasma actuator; DMD; LES; optimization; pulsating flow; strömningskontroll; motståndsminskning; plasma ställdon; DMD; LES; optimering; pulserande flöde; Engineering Mechanics; Teknisk mekanik;

   Abstract : This thesis is motivated by the application of active flow control on the cabin of trucks, thereby providing a new means of drag reduction. Particularly, the work presented strives to identify how plasma actuators can be used to reduce the drag caused by the detachment of the flow around the A-pillars. READ MORE

4. 2. Effect of drag reducing plasma actuators using LES

   Author : Romain Futrzynski; Gunilla Efraimsson; P. Henrik Alfredsson; Emma Alenius; Johan Revstedt; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flow control; drag reduction; plasma actuator; DMD; LES; optimization; pulsating flow; strömningskontroll; motståndsminskning; plasmaaktuator; DMD; LES; optimering; pulserande strömning; Engineering Mechanics; Teknisk mekanik;

   Abstract : The work performed in this thesis explores new ways of reducing the drag of ground vehicles. Specifically, the effect of plasma actuators are investigated numerically with the intention to delay separation around a half-cylinder, a geometry chosen to represent a simplified A-pillar of a truck. READ MORE

5. 3. Passenger Car Wheel Aerodynamics

   Author : Christoffer Landström; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; tyres; wind tunnel; Passenger car aerodynamics; ground simulation; wheel rotation; drag; wheels;

   Abstract : Current and future requirements for efficiency force the automotive industry to consider all aspects of reducing the energy consumption of road going vehicles. An important aspect of reducing fuel consumption is reduced aerodynamic drag, which at highway cruising speeds is dominating the total drag force for both cars and heavy goods vehicles. READ MORE

6. 4. Computational hydrodynamics applied to an America's Cup class keel - best practice and validation of methods

   Author : Sofia Werner; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CFD; America s Cup; induced drag; wind tunnel; winglet; validation; keel; vortex drag; wake survey;

   Abstract : Numerical predictions of the flow around yacht keels can be performed with various types of methods. In this work computational fluid dynamic (CFD) computations are validated against wind tunnel studies of an America's Cup Class keel with the purpose of investigating the accuracy that can be achieved with CFD, which methods that are suitable and how they should be used in the best way. READ MORE

7. 5. The Hydrodynamics of Waterjet/Hull Interaction

   Author : Arash Eslamdoost; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; trim angle; vena-contracta; transom clearance; net thrust; waterjet hull interaction; waterjet propulsion; capture area; exit drag; non-linear free-surface; intake drag; gross thrust; sinkage; streamtube; RANS; thrust deduction; potential flow; VOF;

   Abstract : The objective of the present investigation is to explore the physics behind the waterjet/hull interaction, and in particular the negative thrust deduction often reported in the semi-planing speed range. Another objective is to propose a validated numerical technique for computing the hydrodynamics of waterjet-driven hulls. READ MORE