The Application of Particle Image Velocimetry (PIV) in a Short Duration Transonic Annular Turbine Cascade

A series of experiments have been performed to demonstrate the application of Particle Image Velocimetry (PIV) to turbomachinery flows. The tests were performed at transonic speeds on a fully annular engine size turbine nozzle guide vane. The vane cascade was installed in a short duration Isentropic Light Piston Cascade (ILPC) test facility operating with high inlet turbulence levels. The technique has been shown to map the whole flow field with a resolution of 0.5 mm. The quality of the results obtained are not significantly affected by local turbulence rates. The accuracy of the measurements is put at around 4% of absolute velocity and is limited by the quality of the image on the film plane. The velocities derived from the PIV images have been compared with predictions from a three-dimensional viscous numerical calculation. It is shown that the experimental and predicted results are in good agreement. It is considered that this technique has considerable potential in application to turbomachinery flow field diagnostics.

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The Application of Particle Image Velocimetry (PIV) in a Short-Duration Transonic Annular Turbine Cascade

Journal of Turbomachinery ◽

10.1115/1.2929173 ◽

1992 ◽

Vol 114 (3) ◽

pp. 504-509 ◽

Cited By ~ 17

Author(s):

P. J. Bryanston-Cross ◽

C. E. Towers ◽

T. R. Judge ◽

D. P. Towers ◽

S. P. Harasgama ◽

...

Keyword(s):

Particle Image Velocimetry ◽

Flow Field ◽

Short Duration ◽

Particle Image ◽

Guide Vane ◽

Three Dimensional ◽

Film Plane ◽

Test Facility ◽

Image Velocimetry

A series of experiments have been performed to demonstrate the application of Particle Image Velocimetry (PIV) to turbomachinery flows. The tests were performed at transonic speeds on a fully annular engine size turbine nozzle guide vane. The vane cascade was installed in a short-duration Isentropic Light Piston Cascade (ILPC) test facility operating with high inlet turbulence levels. The technique has been shown to map the whole flow field with a resolution of 0.5 mm. The quality of the results obtained is not significantly affected by local turbulence rates. The accuracy of the measurements is put at around 4 percent of absolute velocity and is limited by the quality of the image on the film plane. The velocities derived from the PIV images have been compared with predictions from a three-dimensional viscous numerical calculation. It is shown that the experimental and predicted results are in good agreement. It is considered that this technique has considerable potential in application to turbomachinery flow field diagnostics.

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Simultaneous Measurement of Free Surface Elevation and Three-Component Velocity Field Around a Translating Surface-Piercing Foil

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.4038586 ◽

2018 ◽

Vol 140 (3) ◽

Author(s):

James Schock ◽

Jason Dahl

Keyword(s):

Particle Image Velocimetry ◽

Free Surface ◽

Velocity Field ◽

Numerical Methods ◽

Flow Field ◽

Particle Image ◽

Laser Sheet ◽

Three Dimensional ◽

Dynamic Mode ◽

Image Velocimetry

Two methods are investigated to simultaneously obtain both three-dimensional (3D) velocity field and free surface elevations (FSEs) measurements near a surface piercing foil, while limiting the equipment. The combined velocity field and FSE measurements are obtained specifically for the validation of numerical methods requiring simultaneous field data and free surface measurements for a slender body shape. Both methods use stereo particle image velocimetry (SPIV) to measure three component velocities in the flow field and both methods use an off the shelf digital camera with a laser intersection line to measure FSEs. The first method is performed using a vertical laser sheet oriented parallel to the foil chord line. Through repetition of experiments with repositioning of the laser, a statistical representation of the three-dimensional flow field and surface elevations is obtained. The second method orients the vertical laser sheet such that the foil chord line is orthogonal to the laser sheet. A single experiment is performed with this method to measure the three-dimensional three component (3D3C) flow field and free surface, assuming steady flow conditions, such that the time dimension is used to expand the flow field in 3D space. The two methods are compared using dynamic mode decomposition and found to be comparable in the primary mode. Utilizing these methods produces results that are acceptable for use in numerical methods verification, at a fraction of the capital and computing cost associated with two plane or tomographic particle image velocimetry (PIV).

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Particle Image Velocimetry (PIV) Investigation of Blade and Purge Flow Impacts on Inter-Stage Flow Field in a Research Turbine

Energies ◽

10.3390/en12071240 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1240 ◽

Cited By ~ 1

Author(s):

Zhenyang Zhang ◽

Hongwei Ma

Keyword(s):

Particle Image Velocimetry ◽

Flow Field ◽

Rotor Blade ◽

Particle Image ◽

Guide Vane ◽

Measurement Techniques ◽

Inlet Guide Vane ◽

Pressure Probe ◽

Image Velocimetry ◽

Purge Flow

Flow field in the inter-stage is of great importance to jet engine turbine performance and efficiency. Investigation of flow fields is limited by the complex geometrical structure. Traditional measurement techniques, such as hot wire, pressure probe and laser Doppler velocimetry (LDV) can hardly obtain a planar information of the flow field simultaneously. To overcome this difficulty, an instantaneous planar velocimetry technique, the particle image velocimetry (PIV) technique is widely employed. However, there is no publication that studied the detailed flow field by PIV in a turbine inter-stage with the consideration of the influence of rotor blade and purge flow. This paper presents a quasi-three dimensional perspective of flow field between inlet guide vane (IGV) and rotor blade in a research turbine inter-stage by using a 2D PIV system. Coherent structures in the flow field are extracted by the proper orthogonal decomposition (POD) method. Time-averaged results show the ellipsoid structures caused by secondary flow in the inter-stage. Rotor blade influence to axial and radial flow is evaluated by time-averaged data and the first order POD mode. Egress of purge flow (9.4% of main annulus flow rate) leads to a domain with 60% axial velocity loss near hub and a growth over three times in radial velocity. POD analysis of purge flow shows detailed flow migration in the whole measurement plane.

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