A videogrammetric technique developed at NASA Langley Research Center has been used at five NASA facilities at the Langley and Ames Research Centers for deformation measurements on a number of sting mounted and semispan models. These include high-speed research and transport models tested over a wide range of aerodynamic conditions including subsonic, transonic, and supersonic regimes. The tech...

The lining of operating high-speed-railway tunnels suffers from cracks, the peeling material, and other deteriorations defects, all which seriously affect driving safety. However, trajectory a falling block tunnel in train wind environment its impact on safety are unknown. To study movement blocks under coupling effect local flow field blocks, three-dimensional gas–solid-coupling numerical calc...

Wind tunnels are being used to study the aerodynamic properties of race cars, fighter planes etc. It allows us to make a reusable prototype and test it in the tunnel. Hypersonic wind tunnels operate at hypersonic speeds ie, with a mach number greater than 6. For doing experiments, it is necessary to maintain a constant pressure in the settling chamber of the tunnel so that we get the desired Ma...

Analysis of the slipstream development around the high-speed trains in tunnels would provide references for assessing the transient gust loads on trackside workers and trackside furniture in tunnels. This paper focuses on the computational analysis of the slipstream caused by high-speed trains passing through double-track tunnels with a cross-sectional area of 100 m2. Three-dimensional unsteady...

The safety of river-crossing tunnels is an important aspect of urban road traffic systems. Previous studies concerning traffic safety mainly focused on urban roads. Given the absence of a number of variables, such as speed and real-time traffic volume, in traffic accident databases, the traffic safety of urban river-crossing tunnels has rarely been studied. This study used the microscopic traff...

It is desirable to test sportswear and sports equipment at exactly the same conditions experienced during use. Although outdoor tests are in many cases the most adequate, they are at the same time quite complex, demand special measurement technology and wearable equipment. Results of such tests are often hard to interpret due to large variations because of rapidly varying ambient conditions and...

a = speed of sound e = integrated amplification ratio for a linear instability, usually from location of first instability to transition k = roughness height Mw = Mach number at the nozzle wall, at the boundarylayer edge M1 = Mach number in the freestream N factor = ln A=A0, the linear-theory amplification ratio from onset of instability A0 usually to measured transition A Pmean = mean pitot pr...

Wind-driven surficial oxygen transfer into stationary water bodies has become increasingly important because the fate of many pollutants in these water bodies is strongly influenced by oxygen mass transfer. There are many existing correlations that can be used for predicting wind-driven surficial oxygen transfer; however, the actual prediction has been difficult because there are large variatio...