Estimation of laser-Doppler anemometry measuring volume displacement in cylindrical pipe flow

Abstract

Laser-Doppler anemometry application in measurements of the 3-D swirl turbulent flow velocity in the cylindrical pipe, behind the axial fan, have been analysed. This paper presents a brief overview of uncertainty sources in the laser-Doppler anemometry measurements. Special attention is paid to estimation of laser-Doppler anemometry measuring volume positioning in cylindrical pipe flow due to optical aberrations, caused by the pipe wall curvature. The hypothesis, that in the central part of the pipe (r/R < 0.6) exists a small, or negligible pipe wall influence on laser- -Doppler anemometry measuring position, is investigate. The required corrections, for measurements of axial, tangential, and radial velocity components such: shift of measuring volume and its orientation are analyzed and determined for used test rig and for some other pipe geometries. [Projekat Ministarstva nauke Republike Srbije, br. TR 35046

Randomness Representation of Turbulence in Canopy Flows Using Kolmogorov Complexity Measures

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Boundary-layer transition detection by thermography and numerical method around bionic train model in wind tunnel test

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Refraction Effect from Beam Refraction by Annular Wall Window in LDA Applications

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