Wing sails offer a different design challenge to those of more conventional soft sail rigs. This study was undertaken in order to assess which parameters influence wingsail performance of C-Class catamarans, and to what extent, the results from the wind tunnel can be applied in the design developments of future wingsails. A combined wing sail and Cclass catamaran was tested in the low-speed sec...

In current design practice, spatiotemporally varying wind loads on buildings are modeled as equivalent static wind loads. This loading description serves as pivotal information for estimating response under the combined action of wind and other loads. This paper presents a framework for evaluating the equivalent static wind load for any given peak response of buildings with uncoupled responses ...

New rotor blades are to be fabricated for the 24 foot diameter, 3-stage axial compressor which provides airflow in the 11by 11-Foot Transonic Wind Tunnel Facility at NASA Ames Research Center in Moffett Field, California. This presents an opportunity to increase the peak Mach number capability of the tunnel by redesigning the compressor for increased pressure ratio. Simulations of the existing ...

The development of Doppler global velocimetry is described. Emphasis is placed on the modifications necessary to advance this nonintrusive laser based measurement technique from a laboratory prototype to a viable wind tunnel flow diagnostics tool. Several example wind tunnel flow field investigations are described to illustrate the versatility of the technique. Flow conditions ranged from incom...

In this study a new passive, large particle impactor (PLPI) (PM<10) was developed and evaluated in a wind tunnel. The PLPI is designed to be isoaxial and isokinetic to enable large particles sampling without bias. The PLPI can provide representative sampling without requiring a mass flowmeter controller or pump. The PLPI is especially useful for aerosol wind tunnel studies to evaluate particle ...

The dynamic longitudinal-stability characteristics of a st,andard wind tunnel interference model have been investigated in free flight over a Mach number range of 0.92 to I, 35.. Measurements of lift-curve slope and manoeuvre margin were obtained, and are compared vjith results from transonic-tunnel tests under low blockage conditions. The analysis was extended to obtain damping derivatives to ...

The aerodynamic behavior of a 48’ yacht rig 3D scale model was characterized by means of wind tunnel tests. The experimental program, performed in the Politecnico di Milano Twisted Flow Wind Tunnel, allowed the aerodynamic forces to be characterized using forced motion tests and the aeroelastic behavior of the sail plan to be studied. Preliminary results are presented with reference to the typi...

The purpose of this paper is to analysis the basic aerodynamic theory of wings and the provide an introduction to wind tunnel testing. This is followed by the result from the wind tunnel testing of a NACA4412 and the analysis of the data. Lift increase at the angle of attack increase at certain point and at this point it become maximum. After that if the angle of attack is increased by further,...

CFD requires validation for complicated flow problems involving complex physics such as turbulence. Wind tunnels are still the most commonly used validation tools for CFD including physical modelling although some limited use of reliable DNS data base for simple geometries is recently becoming possible. One can observe the trend that a higher and higher demand on the accuracy of the wind tunnel...

The aerial transport of tiny arthropods including wing-less species has been well documented. The initiation of aerial dispersal in most instances is not a passive phenomenon, but involves identifiable behaviors in response to specific stimuli. Here we describe a construction of wind tunnel suitable for close-up observation of micro-arthropods behavior under various conditions. The tunnel was m...