Application of Acoustic Metamaterials in Boundary Layer Instability Control

To achieve delay of laminar-to-turbulent transition of boundary layers, the application of acoustic metamaterial concepts is investigated. This is done analytically, numerically and experimentally by studying the interaction between a Helmholtz resonator and a TS wave. A Helmholtz resonator can serve as a meta-atom in a metamaterial. The desired...

Aerodynamics of Platooning Ahmed Bodies: An experimental analysis using large-scale PIV, pressure, and force measurements

Heavy-Duty Vehicles (HDVs) are responsible for a measurable and growing portion of the worldwide greenhouse gas emissions. As aerodynamic drag constitutes the single biggest source of engine power demand for HDVs at highway speeds, aerodynamic improvements are an effective measure to reduce fuel consumption and thus greenhouse gas emissions....

Surface Pressure Measurements using Coaxial Volumetric Velocimetry: Investigation on an Inverted Wing in Ground Effect

In experimental aerodynamics, pressure is an important parameter which provides insight into the various features of the flow around the test object. By obtaining the surface pressure information, various inferences can be drawn such as flow separation, local flow velocity etc. Traditionally, the most common method of obtaining pressure has been...

Time-averaged pressure from Robotic Volumetric PIV

Pressure represents a physical magnitude which allows the characterisation of flow behaviour. Its study is<br/>of great interest for engineering purposes and is broadly reported in the literature. The practical implementation of pressure measurements in industrial wind tunnel facilities involves the use of intrusive pressure probes only able to...

Characterization of junction flow under the influence of passive flow control devices: An experimental study with large-scale tomographic PTV technique

Junction flow denotes the fluid phenomenon where the flow on a flat surface encounters a protuberance. This type of flow, which is highly three-dimensional, turbulent and unsteady, usually leads to the generation of a Horseshoe vortex at the obstacle's leading edge. Existing extensive experimental and numerical studies focus on the inception of...

Drag analysis of full scale cyclist model using large scale 4D-PTV: An accuracy assessment

Laser diagnostic techniques such as Particle Image Velocimetry and Particle Tracking Velocimetry to measure the flow of a fluid around an object have been in prevalence for a few decades. Typically, the fluid, whose motion is of interest, is seeded with micron scale particles and illuminated with a laser. Due to scattering inefficiencies of...