Particle image velocimetry and numerical simulations of the hydrodynamic characteristics of an artificial reef

Thrusters working at low advance coefficients are employed in a wide range of offshore and marine applications on Floating, Production, Storage, and Offloading (FPSO) systems; shuttle tankers; tug boats; and mobile offshore units. Therefore, an understanding of the flow around the thrusters is of great practical interest. Despite this interest, there is lack of knowledge in the description of the hydrodynamic characteristics of a ducted thruster’s wake at bollard pull and low advance coefficient values. This work was aimed at providing detailed data about the hydrodynamic characteristics of a Dynamic Positioning (DP) thruster near wake flow at different low advance coefficient values. Wake measurements were made during cavitation tunnel tests carried out on a ducted propeller model at the Italian Ship Model Basin (INSEAN), Rome, Italy. Through these experiments, the DP thruster near wake velocity components at different downstream axial planes, up to 1.5 diameters downstream, were obtained using a Stereoscopic Particle Image Velocimetry (SPIV) system. These experiments were carried out at different advance coefficient (J) values [bollard pull (J=0), J=0.4 and J=0.45].

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Comparison of direct numerical simulations and particle-image velocimetry data of turbulent channel flow rotating about the streamwise axis

Physics of Fluids ◽

10.1063/1.2760278 ◽

2007 ◽

Vol 19 (8) ◽

pp. 085114 ◽

Cited By ~ 9

Author(s):

I. Recktenwald ◽

T. Weller ◽

W. Schröder ◽

M. Oberlack

Keyword(s):

Particle Image Velocimetry ◽

Numerical Simulations ◽

Channel Flow ◽

Particle Image ◽

Particle Image Velocimetry Data ◽

Turbulent Channel Flow ◽

Direct Numerical Simulations ◽

Image Velocimetry

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A Particle Image Velocimetry-Based Investigation of the Flow Field in an Oblique Jet Impingement Configuration

Journal of Turbomachinery ◽

10.1115/1.4025212 ◽

2013 ◽

Vol 136 (5) ◽

Cited By ~ 5

Author(s):

Sebastian Schulz ◽

Simon Schueren ◽

Jens von Wolfersdorf

Keyword(s):

Particle Image Velocimetry ◽

Flow Field ◽

Numerical Simulations ◽

Particle Image ◽

Jet Impingement ◽

High Energy ◽

Geometric Constraints ◽

Image Velocimetry ◽

Pod Analysis ◽

Cooling Passage

Impinging jets have become an indispensable measure for cooling applications in gas turbine technology. The present study seeks to explore the flow field dynamics inside an enigine-relevant cooling passage of trapezoidal cross-section. The investigated geometry produces a highly complex flow field which was investigated employing particle image velocimetry (PIV). The experiments were accompanied by numerical simulations solving the Reynolds-averaged Navier–Stokes (RANS) equations with FLUENT using the low-Re k-ω-SST (shear stress transport) turbulence model. Additionally, time-resolved pressure measurements were performed utilizing Kulite pressure transducers. The spectral analysis of the transient pressure signal in conjunction with a proper orthogonal decomposition (POD) analysis of the PIV data allows for a detailed insight into the effects of geometric constraints on the fluid dynamic processes inside the geometry. The results are presented for a jet Reynolds number of 45,000 and display a qualitatively fair agreement between the experiments and numerical simulations. Nevertheless, the simulations predict flow features in particular regions of the geometry that are absent in the experiments. Despite the lack of conspicuous high energy modes, the flow was well suited for a POD analysis. Depending on the considered PIV plane, it could be shown that up to 25% of the flow field's total turbulent energy is contained in the first ten POD modes. Additionally, using the first 20 to 60 POD modes sufficed to reconstruct the flow fields with its governing features.

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A Particle Image Velocimetry-Based Investigation of the Flow Field in an Oblique Jet Impingement Configuration

Volume 3A: Heat Transfer ◽

10.1115/gt2013-94780 ◽

2013 ◽

Author(s):

Sebastian Schulz ◽

Simon Schueren ◽

Jens von Wolfersdorf

Keyword(s):

Particle Image Velocimetry ◽

Flow Field ◽

Numerical Simulations ◽

Particle Image ◽

Jet Impingement ◽

High Energy ◽

Geometric Constraints ◽

Image Velocimetry ◽

Pod Analysis ◽

Cooling Passage

Impinging jets have become an indispensable measure for cooling applications in gas turbine technology. The present study seeks to unfold the flow field dynamics inside an enigine-relevant cooling passage of trapezoidal cross-section. The investigated geometry produces a highly complex flow field which was investigated employing Particle Image Velocimetry (PIV). The experiments were accompanied by numerical simulations solving the RANS equations with FLUENT using the low-Re k-ω-SST turbulence model. Additionally, time-resolved pressure measurements were performed utilizing Kulite pressure transducers. The spectral analysis of the transient pressure signal in conjunction with a Proper Orthogonal Decomposition (POD) analysis of the PIV data allows a detailed insight into the effects of geometric constraints on the fluid dynamic processes inside the geometry. The results are presented for a jet Reynolds number of 45,000 and display a qualitatively fair agreement between the experiments and numerical simulations. Nevertheless, the simulations predict flow features in particular regions of the geometry that are absent in the experiments. Despite the lack of conspicuous high energy modes, the flow was well suited for a POD analysis. Depending on the considered PIV plane, it could be shown that up to 25% of the flow field’s total turbulent energy are contained in the first ten POD modes. Additionally, using the first 20 to 60 POD modes sufficed to reconstruct the flow fields with its governing features.

Download Full-text