Integrated Aerodynamic and Structural Measurements of the Gust Response of a Flexible Wing with Robotic PIV

Experimental aeroelastic data is often needed in order to validate the output of fluid-structure interaction numerical simulations or to gain insight into the physics of a problem without the need of intermediate modelling. Traditional measurement approaches in wind tunnels have relied on the simultaneous use of several measurement systems ...

On-site drafting aerodynamics of cyclists using the Ring of Fire

Aerodynamics plays a significant role in the field of cycling as it is the dominant resistive force at racing speeds of 50 km/h. Sporting events involving multiple cyclists leads to aerodynamic interactions between the cyclists and these interactions have been exploited for performance benefits. One such aerodynamic interaction is drafting,...

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...

Accuracy assessment of the Ring of Fire system for on-site aerodynamic drag measurements

The continuous pursuit of reducing drag in many speed sports, such as cycling and ice-skating, demands novel approaches to gain further insight into flow phenomena around athletes. In recent years, the Ring of Fire measurement technique has emerged as a feasible option to visualise and analyse flow structures of transiting objects based on...

Advances and assessment of the Ring of Fire concept for on-site cycling aerodynamics

Aerodynamics investigations in speed sports generally consist of measurements of aerodynamic loads through wind tunnel experiments. Lately, a new technique has emerged, known as the Ring of Fire. It is the only drag measurement technique capable of retrieving flow field data on-site, by using Large-Scale PIV. In this Ring-of-Fire project a Low...

The Flow Topology of the Ahmed Body in Cross-Wind: An Experimental Investigation by means of Robotic Volumetric PIV

The near wake of the Ahmed reference body in the presence of steady cross-wind is investigated experimentally by means of large-scale three-dimensional Particle Image Velocimetry (PIV). A novel experimental technique is employed which exploits coaxial imaging and illumination while relying on Helium Filled Soap Bubble (HFSB) seeding as well as...

Aerodynamic investigation of the near wake flow topology on a two-man bobsleigh

Drag measurements on bluff-bodies such as bobsleighs using force balance systems have been in prevalence for a few decades. However these studies do not reveal anything on the flow behaviour around the body. In the recent past, various flow visualization techniques have been applied to investigate the flow behaviour around bobsleighs. Even...

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...

Robotic Volumetric Particle Tracking Velocimetry by Coaxial Imaging and Illumination

Aerodynamics research and development often involves large-scale and turbulent flows; may this be a rotor flow, the wake of a car, or the flow passing a human athlete to name a few examples. Volumetric particle image velocimetry (PIV) is well suited for the study of such flows. The introduction of Helium Filled Soap Bubbles (HFSB) for wind...

Analysis of an Actuator Disc under Unsteady Loading: Validation of Engineering Models using Experimental and Numerical Methods

Wind turbines operate in the earth's atmospheric boundary layer - an environment where the climate is turbulent and unsteady. In addition, wind turbines usually operate in clusters (wind farms) and are thus subjected to the unsteady wakes generated by upstream turbines. Because of the unsteady inflow, wind turbines suffer from structural fatigue...