Development of an experimental apparatus for flat plate drag measurements and considerations for such measurements

Accurately measuring small changes in aerodynamic drag over a flat surface stands at the core of the development of technologies capable of reducing turbulent friction drag. A wind tunnel drag measurement system was developed which improves significantly on the state of the art. Experimental tests demonstrated that an uncertainty of less than...

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...

Transparent silicon carbide/tunnel SiO₂ passivation for c-Si solar cell front side: Enabling J_sc > 42 mA/cm² and iV_oc of 742 mV

N-type microcrystalline silicon carbide (μc-SiC:H(n)) is a wide bandgap material that is very promising for the use on the front side of crystalline silicon (c-Si) solar cells. It offers a high optical transparency and a suitable refractive index that reduces parasitic absorption and reflection losses, respectively. In this work, we...

Design and Fabrication of on-chip Midinfrared Emitter and LVOF

In this thesis,two essential parts of microspectrometer are designed, fabricated and measured. They are a hot wire of polysilicon with constant temperature profile that used as the IR light source, and the LVOF which is aimed at IR spectral range. In order to have the desired IR source, the hot wire should have temperature distribution as...

External Flow Effects in the Engine/Airframe Integration Testing Technique: A New Thrust/Drag Bookkeeping Approach at the German-Dutch Wind Tunnels

The integration of the engine with the airframe is investigated in the German-Dutch Wind tunnels (DNW) using special scale engines called Turbofan Powered Simulators (TPS). The bookkeeping of thrust and drag must be clear. The TPS thrust is determined under static conditions in a calibration facility, and then subtracted in the wind tunnel test...

Flow visualization of swept wing boundary layer transition

In this work the flow visualization of the transition pattern occurring on a swept wing in a subsonic flow is presented. This is done by means of fluorescent oil flow technique and boundary layer hot-wire scans. The experiment was performed at Reynolds number of 2:15 . 106 and at angle of attack of -3º. At these conditions, three different flows...

Designing the Negative: An exploration of robotic fabrication for customized concrete formworks

Designing the Negative was the title of a Master Studio that took place at the Institute of Architecture and Media of Graz University of Technology during the summer semester of 2012. Students designed and fabricated prototypes of customized concrete formwork as part of their studio assignment. The studio theme forced students to think about...

Wind turbine aerodynamics in yaw: Unravelling the measured rotor wake

Flow measurements for an afterbody in a vertical wind tunnel

Measurements in a 2-D wake and in a 2-D wake merging into boundary layer: Data report

Extensive measurements of mean and fluctuating quantities in a 2-D wake shed from a flat plate and in the flow field of a 2-D wake merging into a boundary layer are described. The 'results are given in tabular and graphical form.

Measurements of the Reynolds stress tensor in a three-dimensional turbulent boundary layer under infinite swept wing conditions

On a wind tunnel model measurements have been made of the six components of the Reynolds stress tensor in a three-dimensional incompressible turbulent boundary layer under infinite swept wing conditions in an adverse pressure gradient, with a three-dimensional separation near the trailing edge. These measurements complement the mean velocity...

Measurement of the Reynolds Stresses in a Circular Pipe as a Means of Testing a DISA Constant-Temperature Hot-Wire Anemometer

Measurements of the turbulent stresses in fully-developed pipe flow have been made as an overall test of the DISA constant-temperature hot-wire anemometer. The measurements were made with single slanting wires and a normal wire. The shearing stress was measured at two Reynolds numbers and compared with values computed from the pressure drop down...