William Thielicke

• Doctor of Philosophy
• Engineer at Optolution GmbH

Wind data collection in the atmospheric boundary layer benefits from short-term wind speed measurements using unmanned aerial vehicles. Fixed-wing and rotary-wing devices with diverse anemometer technology have been used in the past to provide such data, but the accuracy still has the potential to be increased. A lightweight drone for carrying an i...

PIVlab is a free toolbox and app for MATLAB®. It is used to perform Particle Image Velocimetry (PIV) with image data: A light sheet illuminates particles that are suspended in a fluid. A digital camera records a series of images of the illuminated particles. The input images are divided into sub-images (interrogation areas), and for each of these,...

Unlike the majority of sauropsids, which breathe primarily through costal and abdominal muscle contractions, extant crocodilians have evolved the hepatic piston pump, a unique additional ventilatory mechanism powered by the diaphragmaticus muscle. This muscle originates from the bony pelvis, wrapping around the abdominal viscera, extending craniall...

Low-cost illumination systems for Particle Image Velocimetry, such as pulsed laser diodes and LEDs are becoming increasingly popular. Due to the lower power output of these devices in comparison with flashlamp-pumped Nd:YAG lasers, they often have to be operated with longer pulse lengths to achieve a sufficient particle illumination. At some point,...

Low-cost illumination systems for Particle Image Velocimetry, such as pulsed laser diodes and LEDs are becoming increasingly popular. Due to the lower power output of these devices in comparison with flashlamp-pumped Nd:YAG lasers, they often have to be operated with longer pulse lengths to achieve a sufficient particle illumination. At some point,...

In diesem Beitrag wird ein neuartiges, laserbasiertes Messverfahren zur Erfassung der Temperatur von Flüssigkeiten vorgestellt. Das Verfahren basiert auf der temperaturabhängigen Brillouin-Streuung von Laserlicht kombiniert mit einem optischen Filter in Form molekularen Joddampfes. Das Verfahren kann beispielsweise zur örtlich und zeitlich aufgelös...

A laser measuring system was developed and built that allows to optically measure temperature in water using the method of Filtered Brillouin Scattering (FBS). First time-resolved optical temperature measurements were demonstrated. Furthermore, the FBS-system was combined with an LDV to enable simultaneous measurement of flow velocity and therefore...

A laser measuring system was developed and built that allows to optically measure temperature in water using the method of Filtered Brillouin Scattering (FBS). First time-resolved optical temperature measurements were demonstrated. Furthermore, the FBS-system was combined with an LDV to enable simultaneous measurement of flow velocity and therefore...

Crocodilians ventilate their lungs using a novel respiratory mechanism called the hepatic-piston apparatus. Previous work presumes that the hepatic-piston pump is facilitated by a smooth thoracodorsal ceiling. However, the sliding and displacement of the pleura has never been confirmed in living crocodilians. Using ultrasound we recorded images of...

Das von der PTB entwickelte bistatische Doppler-Lidar-System erlaubt die optische Bestimmung des Geschwindigkeitsvektors von Aerosolen in einer Messhöhe von 5 m bis über 250 m. Es wurde eine Vergleichsmessung zwischen dem hochauflösenden Doppler-Lidar der PTB und dem Drohnen-basierten Ultraschall-Anemometer OPTOkopter der OPTOLUTION Messtechnik Gmb...

The OPTOkopter has been developed for airborne, three-dimensional wind measurements and air quality monitoring. A high-precision, 3D wind sensor is carried by a drone that was built from scratch for this purpose. The drone was optimized for long flight times and precision flight. All wind measurements werde validated with the new wind lidar system...

PIVlab ist eine freie MATLAB Implementierung von „Digital Particle Image Velocimetry“ (DPIV), einem berührungslosen Verfahren zur Analyse von Strömungsgeschwindigkeiten. Die Methode nutzt Bilder, die mit einem bekannten Zeitabstand aufgenommen wurden. Aus diesen Bildern wird orts- und zeitaufgelöst die Bewegung von Texturen durch Kreuzkorrelation e...

In aircraft propellers that are used to propel aircraft forward at some speed, propeller blade twist is important to make the individual propeller ‘wings’ operate at a relatively constant effective angle of attack over the full span. Wing twist is sometimes also assumed to be essential in flapping flight, especially in bird flight. For small insect...

The effect of airfoil design parameters, such as airfoil thickness and camber, are well understood in steady-state aerodynamics. But this knowledge cannot be readily applied to the flapping flight in insects and birds: flow visualizations and computational analyses of flapping flight have identified that in many cases, a leading-edge vortex (LEV) c...

It was thought that the aerodynamics of flapping flight in birds is fully understood for quite some time, but recent studies have shown that this is not the case. Bird flight uses aerodynamic mechanisms to generate lift and thrust that differ significantly from conventional aircraft. In slow speed situations, the aerodynamics of bird flight becomes...

Digital particle image velocimetry (DPIV) is a non-intrusive analysis technique that is very popular for mapping flows quantitatively. To get accurate results, in particular in complex flow fields, a number of challenges have to be faced and solved: The quality of the flow measurements is affected by computational details such as image pre-conditio...

Die aerodynamischen Eigenschaften eines Flügels werden maßgeblich durch das Flügelprofil bestimmt. Unter stationären aerodynamischen Bedingungen-welche für die bemannte Luftfahrt bedeutsam sind-ist der Einfluss von Profilwölbung und-dicke im Wesentlichen aufgeklärt. Weitgehend unabhängig von der Reynoldszahl (Re) erhöht die Profilwölbung den Auftri...

Vertical and horizontal force of a flapping-wing micro air vehicle (MAV) has been measured in slow-speed forward flight using a force balance. Detailed information on kinematics was used to estimate forces using a blade-element analysis. Input variables for this analysis are lift and drag coefficients. These coefficients are usually derived from st...

Vertical and horizontal force of a flapping-wing micro air vehicle (MAV) has been measured in slow-speed forward flight using a force balance. Detailed information on kinematics was used to estimate forces using a blade-element analysis. Input variables for this analysis are lift and drag coefficients. These coefficients are usually derived from st...

Flapping-wing MAV designs can potentially benefit from the morphological optimizations of natures flyers, especially in situations where the maximal force-and not the maximal efficiency-is most important: during maneuvering, takeoff and landing. At those moments, unsteady aerodynamics potentially provides the necessary extra forces that keep birds...

Three-dimensional flow field around a flapping bird wing E.J.Stamhuis,W. Thielicke, I. Ros, andJ.Videler (Universityof Groningen) Unsteady effects are more important during flapping flight than previously thought, as studies on hovering insects and more recently on flapping artificial bird wings and on flying bats have shown. Here we present a time...