Full-scale Pressure Measurements Research Articles

PRESSURE MEASUREMENT OF INDUCED EXTERNAL ATMOSPHERE ON THE RUSSIAN SEGMENT OF THE INTERNATIONAL SPACE STATION IN EXPERIMENT «CONTROL»

The goals and objectives of space experiment Control to study parameters of the induced external atmosphere of the Russian Segment of the International Space Station are presented. The processing and analysis procedure for telemetry data obtained using scientific equipment Indicator - ISS is described. Numerical calculations were performed by direct statistical modeling of the flow around the pressure sensor by incoming flotation the Earth's outer atmosphere in the background measurement conditions, as well as in disturbed conditions with two vernier engines of the Zvezda module being operated. A correction function of the pressure sensor is obtained depending on the orientation, temperature factor and selected model of interaction of incident flow molecules with the internal and external device surfaces. The results of numerical modeling of the jet discharges of the the Zvezda vernier engine were compared with the data obtained in full-scale pressure measurements in experiment Control. Key words: pressure sensor, orbital station, induced external atmosphere, direct statistical modeling method.

Sail pressures from full-scale, wind-tunnel and numerical investigations

The main results of a two-year project aimed at comparing full-scale tests, wind tunnel tests, and numerical analysis predictions are presented. Pressure measurements were obtained from both full-scale tests and wind tunnel tests, in upwind and downwind conditions. The upwind wind tunnel test condition was modelled using a Vortex Lattice code, while the downwind wind tunnel test was modelled using a Navier–Stokes code. The pressures obtained from the three different methods are compared on three horizontal sections of the headsail, mainsail and asymmetric spinnaker. In general the pressure from the three experiments showed good agreement. In particular, very good agreement was obtained between the numerical computations and the wind tunnel test results. Conversely, the results from the downwind full-scale pressure measurements showed less similarity due to a slightly tightened trim being used for the spinnaker in the on-water tests. Full-scale tests allow the action of unsteadiness due to the wind, wave and yacht movements to affect the results. This unstable environment caused the asymmetric spinnaker to move around, and a tightened trim was required to prevent the spinnaker from collapsing.

Full-scale pressure measurements on a Sparkman and Stephens 24-foot sailing yacht

The aerodynamics of a Sparkman and Stephens 24-foot sailing yacht was investigated. Full-scale pressure measurements were performed on the mainsail and the genoa in upwind condition. Pressure taps were adopted to measure the pressures on three horizontal sections on the windward and leeward sides of the two sails. Several trims and apparent wind angles were tested. The present paper shows the pressure distributions on the sails and correlates the measured pressures with the flow pattern. In particular, leading-edge laminar separation bubble, turbulent reattachment and turbulent separation are discussed. Pressure measurements are also adopted to draw some trim guidelines.

Equivalent static wind loads on low-rise buildings based on full-scale pressure measurements

This paper addresses the modeling of equivalent static wind loads (ESWLs) on low-rise buildings based on full-scale pressure measurements. The wind load effects of different building frames under alongwind excitations are quantified and compared with those based on the wind loads specified in ASCE 7-05 to examine the adequacy of current design wind load. The ESWLs causing different peak wind load effects of building frames are investigated using a number of approaches, which include the gust response factor (GRF), gust loading envelope (GLE) and load–response-correlation (LRC) approaches. This investigation points out the challenges faced in seeking advanced ESWLs on low-rise buildings which are physically meaningful and insensitive to individual response. Finally, a new approach for modeling ESWLs based on the proper orthogonal decomposition of wind loading field is proposed. The new approach provides a set of ESWLs associated with a small number of important loading modes which are independent of individual response and structural systems, and is able to give accurate prediction of all responses. The proposed approach offers a physically meaningful and convenient modeling of wind loads on low-rise buildings with great potential of design applications.

The distribution and correlation of fluctuating pressures on the Texas Tech Building

Full scale pressure measurements at the Texas Tech Field Research Laboratory have been used to investigate the distribution and correlation of fluctuating pressures on a low rise building. Eigenvector analysis of the covariances indicate that longitudinal and lateral turbulence are responsible for the majority of pressure fluctuations. However, a significant second eigenvector for flow normal to the roof edges corresponds with the rollup and discrete shedding of the separation bubble as a whole. Conditional sampling of peak pressures shows that they are better correlated spatially than the time averaged fluctuations.

Aerodynamic optimization of a group-5 racing car

Aerodynamic aspects of the design of racing cars with low drag and high negative lift are described and their realization shown for the Ford Zakspeed Turbo Capri, a Group-5 racing car. For the aerodynamic shape-optimization, numerous wind-tunnel tests with a 1 5 scale model have been conducted, the results of which are given. The validity of the wind-tunnel tests was confirmed by full-scale pressure measurements and by practical experience with the full-size Ford Zakspeed Turbo Capri car.

Experience in statistical processing of data from full-scale surveys of pressure on sectional linings of town collector tunnels

The suggested method of processing the data from full-scale pressure measurements has a number of advantages over that used at present, as it enables one to display more clearly the laws of pressure distribution. The use of an asymmetrical distribution law and the separate consideration of the distributions for qmax and qmin enables one to set the calculated support pressures more rigorously. This will give rather high values for qmax, which will allow for reserve strength.