Correlative Experimental Study Between The Results of Circulating Water Channel and Towing Tank Tests

Abstract The benchmark experiment research for the maneuverability of a small-scaled ship model is critical for investigating the scaled effect on the maneuvering hydrodynamic derivatives, and validating the CFD technology. Till now, there is little research on the benchmark study and uncertainty analysis for the small-scaled ship which is frequently used in the Circulating Water Channel (CWC). Therefore, an experimental study of the planar motion mechanism (PMM) tests is performed in the CWC of the SJTU. The PMM tests performed in the CWC can avoid some disadvantages of those in the towing tank, such as the limitations on the acquisition time and frequency due to the size of the towing tank, interference of the carriage on the signal acquisition. In addition, the flow field visualization for the tests in the CWC is easier to achieve compared with the experiments in the towing tank, which helps the scholars to understand the characteristic of the wake field during maneuvers. The benchmark ship is the KVLCC2 with a scaled ratio of 1/128.77. The hull forces are recorded and processed to obtain the maneuvering hydrodynamic derivatives. To assess the quality of the acquired data, randomness analysis, stationarity analysis, normality analysis, and statistical convergence are performed for the PMM tests in the CWC for the first time. Finally, the uncertainty analysis (UA) method for the PMM tests performed in the CWC is also developed.

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Dynamic loads and thrust hysteresis of near-surface open propeller in regular head waves-an experimental study in a circulating water channel

Ocean Engineering ◽

10.1016/j.oceaneng.2020.108359 ◽

2021 ◽

Vol 219 ◽

pp. 108359

Author(s):

Wencan Zhang ◽

Ning Ma ◽

Xiechong Gu ◽

Peiyuan Feng

Keyword(s):

Experimental Study ◽

Water Channel ◽

Dynamic Loads ◽

Near Surface ◽

Circulating Water ◽

Head Waves ◽

Regular Head Waves

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Experimental Study of the Fence Wake Manipulation Using Pulsating Jet

Volume 1: Symposia, Parts A, B and C ◽

10.1115/fedsm2009-78366 ◽

2009 ◽

Author(s):

In-Su Kang ◽

Young-Ho Choi ◽

Chel-Woo Park ◽

Hyoung-Bum Kim

Keyword(s):

Boundary Layer ◽

Experimental Study ◽

Separation Bubble ◽

Water Channel ◽

Separated Flow ◽

Flow Region ◽

Velocity Fields ◽

Circulating Water ◽

Pulsating Jet ◽

Upstream Flow

In this study, we experimentally investigated the effect of rear-located pulsating jet to reduce the separated flow region behind the vertical fence. The separation bubble behind the fence is the representative feature of fence wake. Control of fence wake can be used for various purposes such as the reduction of drag, increasing or decreasing the mixing, etc. The vertical fence was submerged in the turbulent boundary layer in the circulating water channel. Reynolds number based on the fence height and upstream flow velocity was 3000. The parameters used for controlling the pulsating jet included the frequency, jet speed and distance between the fence and slit nozzle. In addition, we investigated the effect of continuous jet on the fence wake. Phase averaged DPIV method was applied to measure the instantaneous velocity fields around the fence. And the obtained results were compared with those of uncontrolled fence flow. The obtained results quantitatively show the decrease of reattachment region brought by the pulsating jet. And the specific jet condition which were effective to reduce the separation bubble behind the fence were found.

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Experimental study of slit cylinder vortex shedding in circulating water channel

Proceedings of 2012 International Conference on Measurement, Information and Control ◽

10.1109/mic.2012.6273318 ◽

2012 ◽

Author(s):

Wang Junwei ◽

Yang Jinwen ◽

He Yi ◽

Bao Feng

Keyword(s):

Experimental Study ◽

Vortex Shedding ◽

Water Channel ◽

Circulating Water

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Study on vertical motion reduction of a trimaran based on collaborative controlled appendages

International Journal of Advanced Robotic Systems ◽

10.1177/1729881420976779 ◽

2020 ◽

Vol 17 (6) ◽

pp. 172988142097677

Author(s):

Zhilin Liu ◽

Linhe Zheng ◽

Guosheng Li ◽

Shouzheng Yuan ◽

Songbai Yang

Keyword(s):

Experimental Study ◽

Vertical Motion ◽

Model Tests ◽

Wave Period ◽

Regular Waves ◽

Towing Tank ◽

Vertical Stability ◽

Stabilization Control ◽

Stability Performance

In recent years, the trimaran as a novel ship has been greatly developed. The subsequent large vertical motion needs to be studied and resolved. In this article, an experimental study for a trimaran vertical stabilization control is carried out. Three modes including the bare trimaran (the trimaran without appendages, the trimaran with fixed appendages, and the trimaran with controlled appendages) are performed through model tests in a towing tank. The model tests are performed in regular waves. The range of wave period is 2.0–4.0 s, and the speed of the carriage is 2.93 and 6.51 m/s. The results of the three modes show the fixed appendages and the actively controlled appendages are all effective for the vertical motion reduction of the trimaran. Moreover, the controlled appendages are more effective for the vertical stability performance of the trimaran.

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Experimental Study of a Tanker Ship Squat in Shallow Water

Jurnal Teknologi ◽

10.11113/jt.v66.2477 ◽

2014 ◽

Vol 66 (2) ◽

Author(s):

Mohammadreza Fathi Kazerooni ◽

Mohammad Saeed Seif

Keyword(s):

Experimental Study ◽

Shallow Water ◽

Experimental Approach ◽

Model Tests ◽

Ship Hull ◽

Experimental Results ◽

Shallow Waters ◽

Towing Tank ◽

Ship Model

One of the phenomena restricting the tanker navigation in shallow waters is reduction of under keel clearance in the terms of sinkage and dynamic trim that is called squatting. According to the complexity of flow around ship hull, one of the best methods to predict the ship squat is experimental approach based on model tests in the towing tank. In this study model tests for tanker ship model had been held in the towing tank and squat of the model are measured and analyzed. Based on experimental results suitable formulae for prediction of these types of ship squat in fairways are obtained.

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Spring-Arrangement Effect on Flow-Induced Vibration of a Circular Cylinder

Journal of Vibration Engineering & Technologies ◽

10.1007/s42417-020-00268-5 ◽

2021 ◽

Author(s):

Koki Yamada ◽

Yuga Shigeyoshi ◽

Shuangjing Chen ◽

Yoshiki Nishi

Keyword(s):

Circular Cylinder ◽

Dynamic Model ◽

Geometric Nonlinearity ◽

Water Channel ◽

Fluid Flows ◽

Flow Induced Vibration ◽

Theoretical Evaluation ◽

Circulating Water ◽

Linear Dynamic ◽

Elastically Supported

Abstract Purpose This study elucidated the effect of an inclined spring arrangement on the flow-induced vibration of a circular cylinder to understand if the effect enhances the harnessing of the energy of fluid flows. Method An experiment was conducted on a circulating water channel. A circular cylinder was partially submerged. It was elastically supported by two springs whose longitudinal directions were varied. With the speed of the water flow varied, the vibrations of the circular cylinder were measured. The measured vibrations were interpreted by la linear dynamic model. Results and discussion In a few cases, a jump in response amplitudes from zero to the maximum was observed with the spring inclination at reduced velocities of 6 to 7, whereas gradually increasing response amplitudes were observed in other cases. The inclined spring arrangement achieved greater velocity amplitudes than in cases without spring inclination. A theoretical evaluation of the measured responses indicates that the effect of the inclined springs was caused by geometric nonlinearity; the effect would be more prominent by employing a longer moment lever.

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DESAIN DAN MANUFAKTUR MINI CIRCULATING WATER CHANNEL TANK UNTUK PENGUJIAN PROTOTYPE KAPAL GUNA MENGETAHUI KARAKTERISTIK HIDRODINAMIKA LAMBUNG KAPAL DAN PERILAKU GERAKAN KAPAL

Jurnal Kelautan Indonesian Journal of Marine Science and Technology ◽

10.21107/jk.v13i2.6243 ◽

2020 ◽

Vol 13 (2) ◽

pp. 67-74

Author(s):

Yeddid Yonatan Eka Darma ◽

Galang Sandy Prayogo ◽

Anggra Fiveriati

Keyword(s):

Water Channel ◽

Circulating Water

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Hydrodynamics Around a Deep-Draft Semi-Submersible With Various Corner Shapes

Volume 9: Offshore Geotechnics; Honoring Symposium for Professor Bernard Molin on Marine and Offshore Hydrodynamics ◽

10.1115/omae2018-77135 ◽

2018 ◽

Author(s):

Yibo Liang ◽

Longbin Tao

Keyword(s):

Numerical Model ◽

Experimental Test ◽

Numerical Study ◽

Water Channel ◽

Hydrodynamic Characteristics ◽

Shape Design ◽

Circulating Water ◽

Fluid Physics ◽

Shape Effects ◽

Geometric Study

A numerical study on flow over a stationary deep-draft semi-submersible (DDS) with various corner shapes was carried out to investigate the corner shape effects on the overall hydrodynamics. Three models based on a typical DDS design with different corner shapes were numerically investigated under 45° incidence. The present numerical model has been validated by an experimental test carried out in a circulating water channel. It is demonstrated that, as the corner shape design changed, the hydrodynamic characteristics alter drastically. In addition, the flow patterns were examined to reveal some insights of the fluid physics due to the changing of different corner shape designs. The detailed numerical results from the geometric study will provide a good guidance for future practical designs.

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