SUMMARY : The validity of wind-tunnel simulation of the noise radiated bv a moving source is studied. Theoretical corrections are derived thai allow acoustic measurements in a wind tunnel with microphones outside of the flow to be transposed to a real flight situation. Some corrected coaxial jet data are then compared with real flight data, CONTENTS

The objective of obtaining a spatially standardized steady stream of air across and along the test section of a wind tunnel has been considered by several researchers. When a wind tunnel is manufactured or montage or move to another position, the study about variation of pressure, Mach number, density and temperature distribution, the variation of pitch and yaw components of flow angularity, bo...

An experimental study has been conducted to investigate the static and wind-on performance of two in-house-developed polymer-based pressure-sensitive paints. Platinum tetrakis (pentafluorophenyl) porphyrin and tris-bathophenanthroline ruthenium II are used as the luminophores of these two polymer-based pressure-sensitive paints. The pressure and temperature sensitivity and the photo-degradation...

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...

Wind tunnel experiments have been carried out on a small-scale physical model of a municipal waste landfill (MWL) in the CRIACIV (Research Centre of Building Aerodynamics and Wind Engineering) “environmental” wind tunnel in Prato (Italy). The MWL model simulates a landfill whose surface is higher than the surrounding surface, applying a 1:200 scaling factor. Modelling an area source such as lan...

An investigation into the total blockage effects on aerodynamic drag in closed-wall wind tunnel testing has been carried out by computational fluid dynamics (CFD). The simulation of flow past two different realistic, full-scale, heavy-duty truck models was conducted. The models were placed at different yawing angles in the virtual wind tunnels with blockage ratio of about 10%; which is exactly ...

A boundary layer wind tunnel facility has been adopted in order to conduct experimental measurements of the flow field around a model of the Panorama Giustinelli Building, Trieste (Italy). Information on the main flow structures has been obtained by means of flow visualization techniques and has been compared to the numerical predictions of the vortical structures spread on top of the roof, in ...

In this paper, we present a gas dispersal simulation package which integrates OpenFOAM flow simulation and a filament-based gas propagation model to simulate gas dispersion for compressible flows with a realistic turbulence model. Gas dispersal simulation can be useful for many applications. In this paper, we focus on the evaluation of statistical gas distribution models. Simulated data offer s...

An extensive experimental investigation to understand the aerodynamic behavior of wrap around fin (WAF) missile configuration has been conducted. Various tests using at first a standard model (TTCP) in the trisonic wind tunnel of Imam Hossein University has been performed. The tunnel has attest section of 60×60 cm2 and can operate at Mach numbers of 0.4≤M∞≤2.2 and at attack angles of -4˚≤α≤10˚....

An experimental study was performed to examine the wake characteristics and aeromechanic performance of an innovative twin-rotor wind turbine (TRWT) in comparison with those of a conventional single-rotor wind turbine (SRWT). The comparative study was conducted in a large-scale Aerodynamic/Atmospheric Boundary Layer (AABL) wind tunnel with the TRWT and SRWT model sited in simulated atmospheric ...