Investigation of Cathodic-Arc-Jet Influence on Cross Flow using Particle Image Velocimetry

2015 ◽  
Author(s):  
Igal Kronhaus
Keyword(s):  
Particle Image Velocimetry ◽  
Particle Image ◽  
Cross Flow ◽  
Image Velocimetry ◽  
Cathodic Arc

A Flow Study of Pulsed Jet Cross-Flow Interaction by Micro Particle Image Velocimetry

2006 ◽  
Author(s):  
Kenichi Watanabe ◽  
Tomonori Nakatsuka ◽  
Daichi Suzuki ◽  
Takashi Nagumo ◽  
Masahiro Motosuke ◽  
...  
Keyword(s):  
Reynolds Number ◽  
Particle Image Velocimetry ◽  
Flow Control ◽  
Particle Image ◽  
Low Reynolds Number ◽  
Cross Flow ◽  
Synthetic Jet ◽  
Pulsed Jet ◽  
Micro Particle Image Velocimetry ◽  
Image Velocimetry

Recent development of micro devices is remarkable as in the examples of Micro-TAS, Lab-on-a-chip or ultra micro gas turbine. In order to make the micro devices smaller and more effective, an appropriate use of a micro scale jet as an actuator can be a key technology. Aiming at the development of a measurement system of the micro flow control devices in the future micro aerodynamics, we have established a system to measure a continuous jet, a pulsed jet and a synthetic jet for the flow control in the low Reynolds number air flow with a micro length scale. The two-dimensional flow field around the micro jet using micro particle image velocimetry (PIV) was measured. The jet was injected through the device using an acoustic speaker. It was observed that a saddle point existed at the certain phase where the velocity is 0 at the boundary of the jet blowing and suction phase for the synthetic jet into a still air. It was found that the pulsed jet and the synthetic jet are more effective in the fluid mixing in the low Reynolds number flow than the continuous jet. The dead water region was observed downstream of the jet in case of the jet injection into cross flow. It was recognized that the synthetic jet at the certain oscillation frequency generated a vortex pair near the jet hole.

Research Methodology of Cross-Flow Cylinder Pipe Hydrodynamical

2013 ◽  
Vol 8 (4) ◽  
pp. 110-117
Author(s):  
Konstantin Dobroselsky
Keyword(s):  
Particle Image Velocimetry ◽  
Flow Visualization ◽  
Turbulent Flows ◽  
Research Methodology ◽  
Particle Image ◽  
Cross Flow ◽  
Velocity Fields ◽  
Experimental Setup ◽  
Flow Around A Cylinder ◽  
Image Velocimetry

Experimental setup (hydrodynamic pipe) for the study of turbulent flows has been upgraded. Test experiments with a cross-flow around a cylinder have been carried out. Using the method of flow visualization PIV (Particle Image Velocimetry) the velocity fields around the cylinder for precavitational and cavitation regimes (Re = 2,8 · 105 ) have been obtained

scholarly journals Study on the Application of Particle Image Velocimetry with Resin and Rhodamine B as Alternative Seeding Particles in Pico Hydro Cross Flow Hydro Turbine

2021 ◽  
Vol 85 (1) ◽  
pp. 1-11
Author(s):  
Warjito ◽  
Elang Pramudya Wijaya ◽  
Budiarso ◽  
Sanjaya Baroar Sakti Nasution ◽  
Agil Fadhel Kurnianto
Keyword(s):  
Particle Image Velocimetry ◽  
Rhodamine B ◽  
Particle Image ◽  
Fluid Model ◽  
Cross Flow ◽  
Piv Measurement ◽  
Image Velocimetry ◽  
Flow Phenomena ◽  
Blade Tip ◽  
Volume Of Fluid Model

One of the solutions to overcome the lack of electricity problem in rural area is Crossflow pico-scale hydropower. In improving cross-flow turbine performance, understanding fluid phenomena is needed. Particle image velocimetry (PIV) measurement is one of the methods used to visualize the fluid flow phenomena inside the turbine. Expensive price of seeding particle leads to find the solution for this PIV method. The objective of this study is to use a cheap seeding particle from cheaper materials, mainly resin and rhodamine B. Besides that, in this study, PIV measurement is compared to 2D computational fluid dynamics (CFD) with multiphase volume of fluid model. From the results, several phenomenon can be observed at both of the methods (PIV and CFD) such as separation in the blade tip. Therefore, this study showed that an inexpensive material resin and rhodamine B as a seeding particle has a potential and ability to represent flow inside pico-hydro cross-flow turbine.

Particle image velocimetry and laser Doppler anemometry experimental studies of a compressible short take-off and vertical landing ground vortex flow

2002 ◽  
Vol 216 (4) ◽  
pp. 171-187 ◽  
Author(s):  
N J Lawson ◽  
J M Eyles ◽  
K Knowles
Keyword(s):  
Particle Image Velocimetry ◽  
Vortex Flow ◽  
Particle Image ◽  
Laser Doppler Anemometry ◽  
Cross Flow ◽  
Laser Doppler ◽  
Data Set ◽  
Image Velocimetry ◽  
Vertical Landing ◽  
Dominant Frequencies

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.

scholarly journals Time-resolved particle image velocimetry measurements of a tandem jet array in a cross flow at low velocity ratios

2020 ◽  
Author(s):  
Paul Kristo ◽  
Mark L. Kimber
Keyword(s):  
Particle Image Velocimetry ◽  
Particle Image ◽  
Velocity Ratio ◽  
Cross Flow ◽  
Velocity Fields ◽  
Instantaneous Velocity ◽  
Low Velocity ◽  
Time Resolved ◽  
Turbulent Statistics ◽  
Image Velocimetry

Investigation of the near field dynamics of a single and tandem array of three jets are provided by 2-D time-resolved particle image velocimetry (TR-PIV) measurements. Instantaneous velocity fields are examined in the transverse and spanwise planes with jet to cross flow velocity ratios in the range from 0.9 to 1.7. Previous studies have shown that for high ratios (≥2), the leading jet provides sufficient shielding to ensure that all jets downstream exhibit nearly identical flow characteristics. The current transverse plane measurements exhibit more unique and localized features as a result of the competing effects of pressure gradients and vortex mechanisms assessed via the jet exit profiles, first and second order turbulent statistics, streamline trajectories, recirculation areas, and penetrations depths. Proper orthogonal decomposition (POD) is applied to the spanwise plane instantaneous velocity fields to determine the statistically dominant features of the single and tandem jet configurations at equivalent velocity ratios. The velocity fields are then reconstructed using the truncated POD modes to provide further insight into the shear layer and wake vortices that drive these configurations. Vortex identification algorithms are applied to the reconstructed velocity fields to determine the statistical characteristics of the vortices, including their centroids, populations, areas, and strengths, each of which exhibit largely different dependencies on jet configuration and velocity ratio. Several of the investigated metrics are found to exhibit different behaviors below and above a velocity ratio of unity, and also as a function of increasing velocity ratio between 1 and 2, implying that several transitions mechanisms are present in the low velocity ratio regime investigated herein.

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