Base Flow Modification by Plasma Actuation for Swept Wing Transition Control

In the upcoming decades, a substantial growth in the commercial aviation market is anticipated, accompanied by an increasing societal awareness of global warming. This circumstance necessitates a technological development for emission reduction in future transport aircraft. A method for aerodynamic efficiency improvement is the so-called Laminar...

The Effect Of Wall Heating On Stability And Laminar Breakdown Of Three-Dimensional Boundary Layers: An Experimental Study

An important challenge in the electrification of aircraft propulsion systems is the design of thermal management systems because of an increased heat load that needs to be dissipated. As an alternative to high-drag external heat exchangers, one can consider surface heat exchangers to dissipate the extra thermal energy. This reduces the size of...

Receptivity of Swept Wing Boundary Layers to Surface Roughness: Diagnostics and extension to flow control

The research presented in this thesis focuses on the receptivity to surface roughness of swept wing boundary layers dominated by crossflow instabilities (CFI), providing insights into how surface roughness can be used to passively control the developing instabilities. Discrete roughness elements (DRE) arrays and distributed randomized roughness...

Non-Modal Growth Induced by Discrete Roughness Elements in a Swept Wing Boundary Layer: Modelling and Diagnostics

Laminar-to-turbulent boundary layer transition on the wings and stabilizers of aircraft leads to a large increase in the skin-friction drag they experience during flight. This has motivated prolific research into understanding and delaying the transition process, in an effort to improve the economic and ecological impact of air travel. The swept...

Influence of a forward-facing step on crossflow instability and transition: An experimental study in a swept wing boundary-layer

The market growth expected for commercial aviation in the coming decades and the increasing social awareness regarding the effects of global warming are driving significant technological developments necessary for emission reduction in future transport aircraft. From the aerodynamics perspective, a significant increase in aircraft efficiency can...

An experimental investigation of interaction of crossflow instability with forward facing steps

Experimental measurements are performed on a 45 degree swept flat plate model at the low speed laboratory (LSL) at the Delft University of Technology, in a low turbulence environment to stimulate the development of stationary crossflow. The swept flat plate model is equipped with two linear manual stages to create forward and backward facing...

BiGlobal Stability of Shear Flows: Spanwise & Streamwise Analyses

Laminar-turbulent transition dictates an increase in skin friction. The resulting turbulent skin friction contributes to approximately 40% of the total drag of commercial aircraft. Reducing the turbulent flow region by postponing transition can therefore significantly reduce the carbon footprint and costs of flying. Transition prediction is...