A heavy truck wind tunnel test program is currently underway at the Langley Full Scale Tunnel (LFST). Seven passive drag reducing device configurations have been evaluated on a heavy truck model with the objective of understanding the practical limits to drag reduction achievable on a modern tractor trailer through add-on devices. The configurations tested include side skirts of varying length,...

In the German Aerospace Center, DLR, an internal project has been launched to investigate different UCAV configurations. One aspect, covered by the Institute of Aeroelasticity and the Institute of Aerodynamics and Flow Technology, is the wind tunnel test of a UCAV wing in subsonic and transonic flow. The model shall show measurable static aeroelastic deformations. Main goals of the tests will b...

Research is underway to evaluate the aerodynamic performance of two different wind tunnel test sections. These test sections are the hardwall test section and the hybrid anechoic test section, a novel design where the port and starboard walls are replaced by tensioned Kevlar fabric with the goal of making the walls acoustically transparent yet aerodynamically impervious. Having applications in ...

In this paper, wind tunnel results of a real time optimization of a morphing wing in wind tunnel for delaying the transition towards the trailing edge are presented. A morphing rectangular finite aspect ratio wing, having a wind tunnel experimental airfoil reference cross-section, was considered with its upper surface made of a flexible composite material and instrumented with Kulite pressure s...

The theory, methods, and applications of the videogrammetric model deformation (VMD) measurement technique used at NASA for wind tunnel testing are presented. The VMD technique, based on non-topographic photogrammetry, can determine static and dynamic aeroelastic deformation and attitude of a wind-tunnel model. Hardware of the system includes a video-rate CCD camera, a computer with an image ac...

A computer program has been developed to calculate inviscid transonic flow over a swept wing in a wind tunnel with specified normal flow at the walls. An approximately orthogonal computational grid which conforms to the wing and the tunnel walls was developed for application of the JamesonCaughey finite volume algorithm. the full potential equations in fully conservative form using line relaxat...

By field investigation, it is found that the lower section of transmission tower body is the critical position for insuring tower’s integral stability under strong wind. For improving tower’s wind-resistant performance, the scheme of adding diaphragms at mid-height of diagonal members in lower tower body was proposed and its static effectiveness was researched by static loading tests. Taking th...

Centrospazio has recently developed a small archeated wind tunnel (High Enthalpy Arc-heated Tunnel, HEAT) whose flexible configuration is particularly suited for cost-effective experimentation and research on a wide variety of aerothermodynamic phenomena occurring in high speed flows. The design and operation of the HEAT has involved a number of critical aspects, ranging from the feasibility an...

Hydroelectric power plants’ open-type surge tanks may be built in mountains subject to the provision of atmospheric air. Hence, a ventilation tunnel is indispensable. The air flow in the ventilation tunnel is associated with the fluctuation of water-level in the surge tank. There is a great relationship between the wind speed and the safe use and project investment of ventilation tunnels. To ob...

A three dimensional numerical wind tunnel based on the Navier-Stokes equations for viscous, incompressible fluid and LES method is established. Incoming wind field is generated based on the AIJ guidelines (2004). The numerical wind tunnel is validated against experimental results. A low-rise building with green roof is tested in the numerical wind tunnel. The results show that the green roof re...