On the Runner and Ingate. (Water Model Test for the Gating System of Marine Propeller Casting, 2nd Report)

Purpose The purpose of this work is to visualize the flow behaviour in critical sections of a pressurized gating system. Design/methodology/approach The investigation was carried out using water models of gating system that were designed, invoking the principles of similitude. Water was used as the filling medium, and the manner of flow through various sections of the gating system and the cavity was recorded with a high-speed camera capable of capturing images up to 10,000 frames per second. This was followed by an analysis of the results obtained from each phase. Finally, computer simulations of flow were carried out using commercial software. The manner of filling as observed during experiments and that during simulation were compared so as to draw some useful conclusions on the utility of flow visualization using water models and the capability of software to predict the filling pattern during casting process. It was understood that water models are powerful aids for understanding the intricacies of flow through critical sections of the gating systems. Findings It was observed that water models are a reliable indicator of the mould-filling process. Further, substantial differences in the filling pattern were observed between water model experiments and filling simulation using commercial software. Research limitations/implications The findings are limited to horizontal plate-type castings. Also, the influence of surface roughness in the flow through the runner is not considered. Originality/value This work facilitates understanding of the importance of flow visualization on the quality and reliability of castings.

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Double Acting Tanker: Experiences from Model Tests and Sea Trials

Proceedings of the Institution of Mechanical Engineers Part M Journal of Engineering for the Maritime Environment ◽

10.1243/147509005x10413 ◽

2005 ◽

Vol 219 (3) ◽

pp. 109-119 ◽

Cited By ~ 1

Author(s):

P Trägärdh ◽

P Lindell ◽

N Sasaki

Keyword(s):

Model Test ◽

Oil And Gas ◽

Single Point ◽

Open Water ◽

Model Tests ◽

Water Model ◽

Research Centre ◽

Sea Trial ◽

Cavitation Performance ◽

Ice Conditions

The acronym DAT stands for double acting tanker, a concept where the ship is designed to run astern in heavy ice conditions while remaining hydrodynamically efficient for ahead propulsion in open water conditions. Two large aframax DATs - 106.000 dwt (deadweight tons) each - have been delivered by Sumitomo Heavy Industries to Fortum Oil and Gas OY. They are the first crude carriers built according to the DAT principle and also the first using pod propulsion from the beginning (Fig. 1). They will also be the world's largest crude carriers with ice class 1A super and are primarily intended for year-round transportation of North Sea crude to Fortum's refineries in the Gulf of Finland. The ships were appointed ‘ship of the year’ in Japan in 2003. SSPA was contracted by Sumitomo Heavy Industries to perform model tests. A comprehensive open water model test programme was used to investigate aspects of resistance and propulsion, manoeuvring, and cavitation performance. As the ship is designed to operate both in ahead and astern conditions for prolonged periods of time, most tests were performed both ahead and astern. Also, a simulation study of dynamic positioning at buoy or floating production, storage offshore (FPSO) loading was made by SSPA. Comprehensive tests of the ship's performance in ice were performed in the ice tank at MARC (Masa-Yards Artic Research Centre). The eight-month model testing and development campaign resulted in a ship with excellent propulsion and manoeuvring performance, especially with regard to the high ice class. Sea trials carried out with ship in August 2002 confirmed the results of the model test. Interesting experiences of the model test campaign and comparison between model test and sea trial results are presented, as well as some examples of single-point mooring simulations.

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Foundry Flow Studies Based on Water Model Gating System

International Journal of Aeronautical Science & Aerospace Research ◽

10.19070/2470-4415-2100032 ◽

2021 ◽

pp. 252-257

Author(s):

Sivaraman P ◽

Keyword(s):

Water Model ◽

Gating System

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Installation of a Submerged Buoy for Supporting Risers (BSR) System in Campos Basin Site

Volume 1: Offshore Technology; Polar and Arctic Sciences and Technology ◽

10.1115/omae2011-50167 ◽

2011 ◽

Author(s):

Jairo Bastos de Arau´jo ◽

Jose´ Carlos Lima de Almeida ◽

Antonio Carlos Fernandes

Keyword(s):

Numerical Analysis ◽

Model Test ◽

Water Depth ◽

Water Model ◽

Floating Platform ◽

Mooring Lines ◽

Sea Bottom ◽

Campos Basin ◽

Steel Catenary Risers ◽

Field Location

The BSR (Buoy for Supporting Risers) concept is composed by a submerged buoy anchored to the sea bottom by tethers and intended to support risers coming from the bottom (probably SCRs — Steel Catenary Risers) and going to the floating platform (probably with flexible jumpers). For the case under analysis here, the main dimensions of the BSR prototype are 27.2 m length × 27.2 m width × 5.0 m depth. The paper describes all final full scale installation step so that the BSR may be considered a suitable technology. The installation indeed was the great challenge of this design due the size of the hull. The present work also evaluates numerically and experimentally a specific new manner to install the BSR with the support of auxiliary mooring lines among with the four tethers connected to it. One of the installation premises was to make use of Anchor Handling Supply Vessels instead of Crane Vessels. After this numerical analysis, the work went on by performing model tests that simulates the operation in a deep water model basin using 1:40 scale. The model test anticipated several problems such as the chain stopper weakness in the operation and others as discussed in this paper. As a conclusion the work was devised the most important parameters during the system installation and suggested ways to improve the methodology. In November 2009 the BSR was installed in 500 m of water depth at Congro field location, Campos Basin, offshore Brazil. The tethers were adjusted in January 2010 and in March 2010 two risers were installed. Thenceforward the last edge of this knowledge was considered over passed.

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Improvements of model-test method for cavitation-induced pressure fluctuation in marine propeller

Journal of Hydrodynamics ◽

10.1016/s1001-6058(11)60401-1 ◽

2013 ◽

Vol 25 (4) ◽

pp. 599-605 ◽

Cited By ~ 3

Author(s):

Jeung-Hoon Lee ◽

Jae-Moon Han ◽

Hyung-Gil Park ◽

Jong-Soo Seo

Keyword(s):

Model Test ◽

Pressure Fluctuation ◽

Test Method ◽

Marine Propeller

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Similarity Laws and Model Test Approaches to Determine Hydrodynamic Performance of a Marine Turbine

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.694-697.665 ◽

2013 ◽

Vol 694-697 ◽

pp. 665-672

Author(s):

Wei Chao Shi ◽

Da Zheng Wang ◽

Mehmet Atlar ◽

Dan Wang

Keyword(s):

Model Test ◽

Rotation Speed ◽

Speed Control ◽

Torque Control ◽

Hydrodynamic Performance ◽

Marine Propeller ◽

Power Extraction ◽

Cavitation Tunnel ◽

Extraction Performance ◽

Similarity Laws

The paper presents the methodologies and approaches used in a Cavitation Tunnel or any other circulation channel to investigate the power extraction performance of a marine stream turbine. The paper first introduced model test similarity laws used in the Emerson Cavitation Tunnel (ECT) of Newcastle University to test a marine turbine in marine propeller cavitation tunnel; then based on these similarity laws to investigate the power extraction performance of a marine turbine in different approaches to control the rotation speed, namely: Torque Control and Rotation-speed control. A comparison was made by the tested experimental results. Torque Control is referred to the speed control strategy of using a generator to absorb the torque building up from the stream, on the other hand Rotation-speed control is to use motor to control rotation speed of the turbine. It indicates that both methods can be employed to investigate the hydro performance of marine stream turbine, with wider range of TSR can Rotation-speed Control test.

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