Search results for "Pitot tube"

A mathematical model of the self-averaging Pitot tube

2005

Abstract Flowmeters with self-averaging Pitot tubes are more and more often applied in practice. Their advantages are practically no additional flow losses, usability in the case of high temperature of fluids and simplicity of fitting. A mathematical model of a self-averaging Pitot tube including the influence of the probe shape, selected constructional features and flow conditions on the quantity of differential pressure gained has been given in this paper. The values and ranges of variations of the coefficients established for the model have been assessed on the basis of the numerically computed velocity and pressure fields around and inside the probe. Velocity and pressure fields were ca…

Low-cost underwater navigation systems by multi-pressure measurements and AHRS data

2017

This paper deals with accurate navigation for underwater remotely operated vehicles. A feasibility study for a multi-pressure device to be mounted on an ROV is presented. The device can provide accurate estimates of a ROV orientation and angular speed. It is based on the well-known total pressure principle, also used in a Pitot tube, and allows reconstruction of static and dynamic pressures, which in turn provide good estimates of the ROV's orientation and rotational speed, respectively. An appealing feature of the proposed device is its ability to provide accurate estimates even for low-speed movements.

Validity of a novel device for indoor analysis of cyclists' drag area

2021

Cyclists need to measure aerodynamic resistance accurately and reliably, as well as economically. Devices such as Notio Aerostick, an equipment device that includes one pitot tube, have appeared for this purpose. The aim of this study is, therefore, to test the reliability and degree of agreement in the evaluation of the CdA (coefficient of aerodynamic drag), assessed by means of the Notio Aerostick compared to the Virtual Elevation (VE) and Martin mathematical models.Seventeen professional cyclists rode in a 250-metre-long velodrome covered with a concrete surface with their own time trial bikes. Each cyclist completed three rides of 15 laps at constant speed for the evaluation of the CdA,…

2016

Abstract. Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular, for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable to different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions i…

Gas jet studies towards an optimization of the IGISOL LIST method

2011

Abstract Gas jets emitted from an ion guide have been studied as a function of nozzle type and gas cell-to-background pressure ratio in order to obtain a low divergent, uniform jet over a distance of several cm. The jet has been probed by imaging the light emitted from excited argon or helium gas atoms. For a simple exit hole or converging-diverging nozzle, the jet diameter was found to be insensitive to the nozzle shape and inlet pressure. Sonic jets with a FWHM below 6 mm were achieved with a background pressure larger than 1 mbar in the expansion chamber. The measurements are supported by the detection of radioactive 219 Rn recoils from an alpha recoil source mounted within the gas cell.…