nowadays, we live in a world which quality, speed, accuracy and cost are the most important parameters in parts' design and manufacturing. due to the complexity of part manufacturing, traditional and nontraditional manufacturing techniques are used. aerodynamic tests usually requires one or several models for testing in wind tunnels and these models typically have particular complexities in whi...

A primary air velocity meter calibration standard comprising of a precisely controlled wind tunnel system and a Laser Doppler Anemometry (LDA) system was developed for the calibration of air velocity meters from 0.2 m/s to 60 m/s with measurement uncertainties of less than 0.18% to 0.63%. The LDA system is used to verify the wind speed in the test section of the wind tunnel, and provide traceab...

Numerous vibration control techniques, employing both passive and active methods, have been developed and tested over the last several decades. Some of these techniques are in widespread use, while others have rarely or never left the laboratory. This paper considers the value that vibration damping and control of aircraft fins and appendage structures can have in reducing loads and subsequent ...

Wind-flow pattern over embankments involves an overexposure of the rolling stock travelling on them to wind loads. Windbreaks are a common solution for changing the flow characteristic in order to decrease unwanted effects induced by the presence of cross-wind. The shelter effectiveness of a set of windbreaks placed over a railway twin-track embankment is experimentally analysed. A set of two-d...

Our study is based on a great number of CFD (computational fluid dynamics) simulations to evaluate wind comfort at the pedestrian level. This article explains the method used to validate our CFD simulations carried out with the FLUENT software. This validation is based on a comparison between our simulated results and wind tunnel tests for three different building contexts: a single building, t...

Wind erosion threatens soil productivity and air quality in the Columbia Plateau region of the Pacific Northwest United States. Management practices are sought that will abate erosion, but limitations exist in measuring the effectiveness of these practices in reducing erosion. Portable wind tunnels are ideal tools that can be used to assess the impact of management practices on erosion. A porta...

Structural instability caused by self exciting aerodynamic forces (flutter) can be used as an effective input source for small scale energy harvesters. The self exciting aerodynamic force exerted on a T-shape cantilever causes periodic vibration, which can be converted into electric power through an electromagnetic transducer. Due to the complexities inherent in the fluid-structure interaction ...

In the early design phase of automotive sector, the flow field around the vehicle is important in decision making on design changes. It would consume a lot of money and time for multiple prototypes development if adopt traditional testing method which is wind tunnel test. Thus, numerical method such as Computational Fluid Dynamics (CFD) simulation plays an important role here. It is very often ...

Due to their size, small rotorcraft are vulnerable to external flow disturbances that are challenging to flight stability and control. This paper describes preliminary results from using onboard flow measurements to augment inertial sensors for attitude control. We derive a dynamic model that captures the aerodynamic effects of wind on a single degree-of-freedom tandem-rotor test stand. A pair ...

A dedicated 4-m-high vertical wind tunnel has been designed and constructed at the University of Geneva in collaboration with the Groupe de compétence en mécanique des fluides et procédés énergétiques. With its diverging test section, the tunnel is designed to study the aero-dynamical behavior of non-spherical particles with terminal velocities between 5 and 27 ms(-1). A particle tracking veloc...