Comparison of Particle Image Velocimetry and Laser Doppler Anemometry measurement methods applied to the oil–water flow in horizontal pipe

A particle image velocimetry (PIV) and laser Doppler anemometry (LDA) study of a scaled short take-off and vertical landing (STOVL) ground vortex flow is presented. The scaled flow features a compressible impinging jet in cross-flow with a moving ground plane. Mean and transient PIV and LDA velocity data are recorded from the ground vortex about the jet centre-line over a range of nozzle pressure ratios (NPR s) from 2.3 to 3.7, nozzle height—diameter ratios ( h/dn) from 3 to 10 (where dn = 12.7 mm) and cross-flow velocities (V∞) from 10 to 20 m/s, corresponding to effective velocity ratios of 19 < Ve−1 < 38. For each condition, 72 PIV vector maps were taken from the ground vortex region to generate an instantaneous and time-average data set. From the instantaneous data, a cinematic sequence was used to track the ground vortex position, which was found to fluctuate longitudinally by a root mean square distance of up to 4.47 dn and vertically by up to 2.18 dn. From the time-averaged PIV measurements, selected LDA pointwise data were taken at the average ground vortex core. Subsequent spectral analysis of the PIV time series showed the ground vortex position to fluctuate at dominant frequencies of between 2.5 and 5 Hz while the LDA data showed the velocity to fluctuate by dominant frequencies ranging between 1 and 30 Hz.

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Laser Doppler anemometry (LDA) and particle image velocimetry (PIV) for marine environments

Subsea Optics and Imaging ◽

10.1533/9780857093523.3.353 ◽

2013 ◽

pp. 353-379e ◽

Cited By ~ 1

Author(s):

J.K. Sveen

Keyword(s):

Particle Image Velocimetry ◽

Particle Image ◽

Laser Doppler Anemometry ◽

Laser Doppler ◽

Marine Environments ◽

Image Velocimetry

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Investigations on Slug Flow in a Horizontal Pipe Using Stereoscopic Particle Image Velocimetry and CFD Simulation With Volume of Fluid Method

Volume 3: Thermal-Hydraulics; Turbines, Generators, and Auxiliaries ◽

10.1115/icone20-power2012-54591 ◽

2012 ◽

Cited By ~ 1

Author(s):

Marek Czapp ◽

Matthias Utschick ◽

Johannes Rutzmoser ◽

Thomas Sattelmayer

Keyword(s):

Particle Image Velocimetry ◽

Slug Flow ◽

Particle Image ◽

Volume Of Fluid ◽

Stereoscopic Particle Image Velocimetry ◽

Horizontal Pipe ◽

Pressurized Water ◽

Cooling Circuit ◽

Image Velocimetry ◽

Slug Flows

Investigations on gas-liquid flows in horizontal pipes are of immanent importance for Reactor Safety Research. In case of a breakage of the main cooling circuit of a Pressurized Water Reactor (PWR), the pressure losses of the gas-liquid flow significantly govern the loss of coolant rate. The flow regime is largely determined by liquid and gas superficial velocities and contains slug flow that causes high-pressure pulsations to the infrastructure of the main cooling circuit. Experimental and numerical investigations on adiabatic slug flow of a water-air system were carried out in a horizontal pipe of about 10 m length and 54 mm diameter at atmospheric pressure and room temperature. Stereoscopic high-speed Particle Image Velocimetry in combination with Laser Induced Fluorescence was successfully applied on round pipe geometry to determine instantaneous three-dimensional water velocity fields of slug flows. After grid independence studies, numerical simulations were run with the open-source CFD program OpenFOAM. The solver uses the VOF method (Volume of Fluid) with phase-fraction interface capturing approach based on interface compression. It provides mesh refinement at the interfacial area to improve resolution of the interface between the two phases. Furthermore, standard k-ε turbulence model was applied in an unsteady Reynolds averaged Navier Stokes (URANS) model to resolve self-induced slug formation. The aim of this work is to present the feasibility of both relatively novel possibilities of determining two-phase slug flows in pipes. Experimental and numerical results allow the comparison of the slug initiation and expansion process with respect to their axial velocities and cross-sectional void fractions.

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