Search for dissertations about: "optimal perturbations"

Showing result 1 - 5 of 28 swedish dissertations containing the words optimal perturbations.

2. 1. Optimisation and control of boundary layer flows

   Author : Antonios Monokrousos; Dan S. Henningson; Per Lötstedt; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary layer; control; estimation; optimal disturbances; Lagrange method; Engineering mechanics; Teknisk mekanik;

   Abstract : Both optimal disturbances and optimal control are studied by means of numerical simulations for the case of the flat-plate boundary-layer flow. The optimisation method is the Lagrange multiplier technique where the objective function is the kinetic energy of the flow perturbations and the constraints involve the linearised Navier–Stokes equations. READ MORE

4. 2. Optimisation and control of shear flows

   Author : Antonios Monokrousos; Dan S. Henningson; Laurette Tuckerman; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shear flows; flow control; optimal disturbances; Lagrange method; transition to turbulence; non-linear dynamics; Engineering mechanics; Teknisk mekanik;

   Abstract : Transition to turbulence and flow control are studied by means of numerical simulations for different simple shear flows. Linear and non-linear optimisation methods using the Lagrange multiplier technique are employed. READ MORE

5. 3. Optimization-based coordination strategies for connected and autonomous vehicles

   Author : Robert Hult; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Model Predictive Control; Optimization; Optimal Control; Connected Automated Vehicles; Intersection Coordination;

   Abstract : Automated vehicles (AV) are expected to reach the consumer market within the next decade. Once AVs become ubiquitous, they could resolve difficult traffic situations through communication-based cooperation. READ MORE

6. 4. Active Control and Modal Structures in Transitional Shear Flows

   Author : Onofrio Semeraro; Dan Henningson; Bernd Noack; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flow control; flat-plate boundary layer; optimal controllers; model reduction; turbulent jet; POD; DMD; Koopman modes;

   Abstract : Flow control of transitional shear flows is investigated by means of numerical simulations. The attenuation of three-dimensional wavepackets of Tollmien-Schlichting (TS) and streaks in the boundary layer is obtained using active control in combination with localised sensors and actuators distributed near the rigid wall. READ MORE

7. 5. On stability, transition and turbulence in three-dimensional boundary-layer flows

   Author : Seyed Mohammd Hosseini; Ardeshir Hanifi; Spencer Sherwin; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Receptivity; stability; optimal growth; three-dimensional bound- ary layers; crossflow instability; roughness control; freestream turbulence; sec- ondary instability; transition; turbulence;

   Abstract : A lot has changed since that day on December 17, 1903 when the Wright brothers made the first powered manned flight. Even though the concepts behind flying are unaltered, appearance of stat-of-the-art modern aircrafts has undergone a massive evolution. READ MORE