INSIGHTS INTO THE FLOW WITHIN THE WELL DOCK OF A MOTHERSHIP DURING FEEDER VESSEL DOCKING MANOEUVRES

2021 ◽  
Vol 162 (A1) ◽  
Author(s):  
N T M Johnson ◽  
G J Macfarlane ◽  
J T Duffy ◽  
I Penesis ◽  
R J Ballantyne
Keyword(s):  
Measurement Techniques ◽  
Confined Water ◽  
Water Effect ◽  
Operational Parameters ◽  
Complex Flows ◽  
Sea Transport ◽  
Experimental Campaign ◽  
Feeder Vessel ◽  
Novel Concept ◽  
Optimum Solution

An experimental campaign has been undertaken to explore the flow around a feeder vessel as it manoeuvres in and out of the well dock of a mothership. The parent hulls for this study are drawn from the floating harbour transhipper concept created by Sea Transport Corporation. Laser measurement techniques have been employed to analyse the flow field within the well dock while the feeder vessel both enters and departs. For the Master of the feeder vessel to safely perform these manoeuvres, the complex flows resulting from the highly confined nature of the well dock concept need to be understood and potentially mitigated. It is shown that the inclusion of vents in the well dock can significantly influence the flow and that their effectiveness is determined by the size of the vents. This study further progresses the authors’ recent work on the same novel concept where the confined water effect of the well dock and inclusion of vents is quantified for both the seakeeping behaviour and the docking/departure performance. It is concluded that the use of vents is very beneficial when a feeder vessel docks or departs the well dock, however a compromise on the vent size must be reached in order to reduce adverse effects on feeder vessel motions when docked and exposed to a seaway. It is likely that the optimum solution, that covers all operational parameters, only requires the inclusion of relatively small vents.

Insight into the Flow Within the Well Dock of a Mothership During Feeder Vessel Docking Manoeuvres

2020 ◽  
Vol 162 (A1) ◽  
Author(s):  
N T M Johnson ◽  
G J Macfarlane ◽  
J T Duffy ◽  
I Penesis ◽  
R J Ballantyne
Keyword(s):  
Measurement Techniques ◽  
Confined Water ◽  
Operational Parameters ◽  
Complex Flows ◽  
Sea Transport ◽  
Experimental Campaign ◽  
Feeder Vessel ◽  
Novel Concept ◽  
Optimum Solution ◽  
Insight Into

An experimental campaign has been undertaken to explore the flow around a feeder vessel as it manoeuvres in and out of the well dock of a mothership. The parent hulls for this study are drawn from the floating harbour transhipper concept created by Sea Transport Corporation. Laser measurement techniques have been employed to analyse the flow field within the well dock while the feeder vessel both enters and departs. For the Master of the feeder vessel to safely perform these manoeuvres, the complex flows resulting from the highly confined nature of the well dock concept need to be understood and potentially mitigated. It is shown that the inclusion of vents in the well dock can significantly influence the flow and that their effectiveness is determined by the size of the vents. This study further progresses the authors’ recent work on the same novel concept where the confined water effect of the well dock and inclusion of vents is quantified for both the seakeeping behaviour and the docking/departure performance. It is concluded that the use of vents is very beneficial when a feeder vessel docks or departs the well dock, however a compromise on the vent size must be reached in order to reduce adverse effects on feeder vessel motions when docked and exposed to a seaway. It is likely that the optimum solution, that covers all operational parameters, only requires the inclusion of relatively small vents.

scholarly journals Biosorption of Pb2+ and Cd2+ from Simulated Wastewater Using Melina (Gmelina arborea) Tree Leaves Powder

2018 ◽  
pp. 1-12
Author(s):  
N. O. Ilelaboye ◽  
A. A. Oderinde
Keyword(s):  
Metal Ions ◽  
Waste Treatment ◽  
Anthropogenic Activities ◽  
Freundlich Isotherm ◽  
Solution Concentration ◽  
Isotherm Models ◽  
Operational Parameters ◽  
Solution Ph ◽  
Separation Parameter ◽  
Optimum Solution

Increased anthropogenic activities have led to serious environmental problems due to pollution caused by toxic materials such as heavy metals whose levels are rising in the environment. The inefficiency and high cost of conventional methods of waste treatment have prompted the investigation of environmentally friendly and cheaper methods of treatment using natural products. In this study, G. arborea leaves powder was investigated with a view of using it as cheap material for the biosorption of Pb2+ and Cd2+   from wastewater. The effects of operational parameters like pH, biosorbent dose [g/L], initial metal ions concentration [mg/L], contact time [minutes] and stirring speed [rpm] on the biosorption efficiency [%] were determined. The optimum solution pH for Pb2+ and Cd2+adsorption was 5.0 and peak adsorption of 91.33% and 82.53% for Pb2+ and Cd2+, respectively. 5 g/L Melina leaves were enough to achieve peak removal of both metal ions. The removal of the metal ions was comparatively quick, and stability was achieved after 30 minutes. The optimum stirring speed was 250 rpm for both metal ions. The uptake efficiency of the biosorbent was determined by Langmuir and Freundlich isotherm models. The value of Langmuir isotherm separation parameter [RL] of Pb2+ ion [0.0446 - 0.78125] and Cd2+ [0.1005- 0.9482] were within range of 0 -1 indicating favorable biosorption for both metal ions. The degree of non-linearity [n] values between Pb2+ [12.79] and Cd2+ [11.79] solution concentration and biosorption in Freundlich equation were greater than 1, indicating physical biosorption of Pb2+ and Cd2+ on to G. arborea leaves. G. arborea can serve as efficient biosorbent not only for Pb2+ and Cd2+ ions but also for other heavy metal ions in a wastewater stream

CFD Study of Ship-to-Bank Interaction

2017 ◽  
Vol Vol 159 (A3) ◽  
Author(s):  
Y K Kim ◽  
E Y K Ng
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Pressure Field ◽  
Physical Phenomenon ◽  
Experimental Studies ◽  
Container Ship ◽  
Confined Water ◽  
Water Effect ◽  
Computational Approaches ◽  
Shallow Water Effect

Ship-to-bank interaction is a complex physical phenomenon that involves not only in the asymmetric pressure field near banks or channels but also shallow water effect. Traditionally many experimental studies were carried out in this field. As numerical method is getting popular, there were various computational approaches as well. In this study, flow around a container ship in confined water is investigated with the open source CFD (Computational Fluid Dynamics) toolbox, OpenFOAM. Computations with several bank arrangements and different settings are performed. The OpenFOAM results are also compared to experiment results for validation.

The Floating Harbour Transhipper: New-Generation Transhipment of Bulk Ore Products

2015 ◽  
Author(s):  
Gregor J. Macfarlane ◽  
Nicholas T. M. Johnson ◽  
Lauchlan J. Clarke ◽  
Ross J. Ballantyne ◽  
Kevin A. McTaggart
Keyword(s):  
Deep Water ◽  
Scale Model ◽  
Experimental Program ◽  
Material Transfer ◽  
Mining Operations ◽  
Sea Transport ◽  
Large Bulk ◽  
Physical Scale ◽  
Seakeeping Performance ◽  
Feeder Vessel

Bulk products such as iron ore and coal are usually shipped directly from shore facilities using large bulk carriers. This often involves significant cost due to major dredging operations, long jetties, large storage sheds and the acquisition of large tracts of coastal land. The costs of direct shore to an ocean-going export vessel (OGV) loading often run into billions of dollars — prohibitive for small- to medium-scale mining operations, particularly in remote regions with only distant access to deep water ports. The current industry standard for mitigating these issues is transhipping; the bulk cargo is transported from a smaller shore based facility to the export vessel moored in deep water by a small feeder vessel. Transhipment, while mitigating many of these issues, does introduce other concerns with respect to limiting seastate, environmentally harmful dust and potential spillage during materials transfer. The Australian company Sea Transport Corporation and the Australian Maritime College at the University of Tasmania are developing new technology for bulk ore transhipment: the floating harbour transhipper (FHT). The FHT is essentially a large floating warehouse with an aft well dock to support material transfer operations from the feeder vessel. The major advantages to the mining export industry are in the form of environmental and economic improvements, in some cases completely avoiding expensive dredging while minimising the environmentally invasive onshore infrastructure. In addition, the whole process is enclosed, therefore eliminating grab spillage and dust transport issues common to other transhipping methods. This paper presents an overview of the main hydrodynamic issues currently being investigated: primarily the interaction between multiple floating bodies close to one another in a seaway. The two primary ship-to-ship interactions that are being investigated are the effects experienced by the feeder vessel when it is docking or undocking within the FHT well dock and the interactions between the three vessels when operating in close proximity in an open seaway. A combination of physical scale model experiments and numerical techniques is employed, with a significant portion of the experimental program dedicated to the validation of the numerical simulation codes used to investigate the behaviour of the vessels. ShipMo3D is an object based library developed by DRDC for the purpose of analysing the seakeeping performance of vessels operating in a seaway in either the frequency or time domain. The capabilities of ShipMo3D are applied to this novel application in an attempt to provide realistic simulations of the interaction between the vessels of the FHT system. DualSPHysics, an open source Smoothed Particle Hydrodynamics (SPH) code, is being applied to the domain within the very restricted water environment of the FHT well dock to investigate the fluid flow behaviour and the effect that this has on the feeder vessel when entering/exiting.

Mass transfer in falling film microreactors: measurement techniques and effect of operational parameters

2019 ◽  
Vol 0 (0) ◽  
Author(s):  
Ali Alhafiz Mohammed ◽  
David Lokhat
Keyword(s):  
Mass Transfer ◽  
Measurement Techniques ◽  
Process Intensification ◽  
Liquid Films ◽  
Falling Film ◽  
Operational Parameters ◽  
Transfer Enhancement ◽  
Mass Transfer Enhancement ◽  
The Relationship ◽  
Common Target

Abstract Falling film microreactors have contributed to the pursuit of process intensification strategies and have, over the years, been recognized for their potential in performing demanding reactions. In the last few decades, modifications in the measurement techniques and operational parameters of these microstructured devices have been the focus of many research studies with a common target on process improvement. In this work, we present a review dedicated to falling film microreactors, focusing on the recent advances in their design and operation, with particular emphasis on mass transfer enhancement. Analysis of the recent techniques for the measurement of mass transfer as well as the operational parameters used and their effect on the target objective, particularly in the liquid phase (being the limiting phase reactant), are included in the review. The relationship between the hydrodynamics of falling thin liquid films and the microreactor design, the discrepancies between measured and model results, the major challenges, and the future outlook for these promising microreactors are also presented.

Anomalous response of supported few-layer hexagonal boron nitride to DC electric fields: a confined water effect?

2012 ◽  
Vol 23 (17) ◽  
pp. 175703 ◽  
Author(s):  
C K Oliveira ◽  
M J S Matos ◽  
M S C Mazzoni ◽  
H Chacham ◽  
B R A Neves
Keyword(s):  
Boron Nitride ◽  
Electric Fields ◽  
Hexagonal Boron Nitride ◽  
Confined Water ◽  
Water Effect ◽  
Dc Electric Fields

Improvement of the Delaunay-Tessellation Particle Tracking Algorithm in the Flow Visualization Research

2013 ◽  
Vol 411-414 ◽  
pp. 2134-2137
Author(s):  
Yang Zhang ◽  
Yuan Wang ◽  
Bin Yang
Keyword(s):  
Flow Visualization ◽  
Particle Tracking ◽  
Particle Tracking Velocimetry ◽  
Simple Structure ◽  
High Accuracy ◽  
Tracking Algorithm ◽  
Delaunay Tessellation ◽  
Complex Flows ◽  
Particle Tracking Algorithm ◽  
Novel Concept

The particle tracking velocimetry (PTV) algorithm is one of the most important branches in the flow visualization research. An efficient two-frame PTV based on Delaunay tessellation was updated by a novel concept called Dual Computation. The updated algorithm was tested using CFD flows with changeable parameters and random erasing of particles as perturbation. In addition to the simple structure and the minimal dependence on algorithmic assumptions, the advantages of this updated algorithm also include the high accuracy in addressing complex flows with noticeable ratio of particles having no match.

Turbulence Field Measurements at the Exit of a Combustor Simulator Dedicated to Hot Streaks Generation

2015 ◽  
Author(s):  
Tommaso Bacci ◽  
Bruno Facchini ◽  
Alessio Picchi ◽  
Lorenzo Tarchi ◽  
Charlie Koupper ◽  
...  
Keyword(s):  
Measurement Techniques ◽  
Field Measurements ◽  
Time Correlation ◽  
Test Point ◽  
Lean Burn ◽  
Experimental Campaign ◽  
Turbulence Decay ◽  
Flow Turbulence ◽  
University Of Florence ◽  
Real Scale

In order to deepen the knowledge of the interaction between modern lean burn combustors and high pressure turbines, a real scale annular three sector combustor simulator has been assembled at University of Florence, with the goal of investigating and characterizing the generated flow field. To generate hot streaks and simulate lean burn combustors behavior, the rig is equipped with axial swirlers, fed by main air flow that is heated up to 531 K, and liners with effusion cooling holes that are fed by air at ambient temperature. The three sector configuration is used to reproduce the periodicity on the central sector. Ducts of different lengths have been mounted on the swirlers to reduce the interaction of the mainstream with the coolant. Such configurations have been tested, using different measurement techniques, in order to highlight the differences in the resulting flow fields. The work presented in this paper shows the experimental campaign carried out to investigate the flow turbulence at combustor exit, in isothermal conditions, by means of hot wire anemometry. The goal has been achieved by investigating each test point twice, using an automatic traverse system equipped, in turn, with two split-fiber probes, that allow to measure the velocity components on two planes orthogonal to each other. A method for the time correlation of the signals obtained by the two different tests has been used. In order to analyse the turbulence decay towards the vanes location, such measurements have been performed on two different planes: one located in correspondence of the combustor exit and the further one placed downstream, in the virtual location of the vanes leading edges.

Performance Analysis and Detailed Experimental Results of the First Liquid Air Energy Storage Plant in the World

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
A. Sciacovelli ◽  
D. Smith ◽  
M. E. Navarro ◽  
A. Vecchi ◽  
X. Peng ◽  
...  
Keyword(s):  
Energy Storage ◽  
Storage Capacity ◽  
Storage Systems ◽  
Operational Parameters ◽  
Electricity Storage ◽  
Experimental Campaign ◽  
The World ◽  
Power Storage ◽  
The University ◽  
And Storage

Liquid air energy storage (LAES) is a technology for bulk electricity storage in the form of liquid air with power output potentially above 10 MW and storage capacity of 100 s MWh. In this paper, we address the performance of LAES and the experimental evidences gathered through the first LAES pilot plant in the world developed by Highview power storage at Slough (London) and currently installed at the University of Birmingham (UK). We developed a numerical model of LAES plant and carried out an experimental campaign to gather new results which show the LAES operating principles, the reliability of the technology, the startup/shut down performance, and the influence of operational parameters. In summary, this work (a) contributes to the advancement of thermomechanical storage systems, (b) provides new experimental evidences and results for LAES technology, and (c) highlights the crucial aspects to necessarily improve the performance of LAES.

Monitoring and Performance Evaluation of Plastic Cleanup Systems: Part II — Results and Analysis

2020 ◽  
Author(s):  
Bruno Sainte-Rose ◽  
Hendrik Wrenger ◽  
Ivan Soares ◽  
Cosme Mosneron-Dupin ◽  
Clara Duval ◽  
...  
Keyword(s):  
Linear Model ◽  
Performance Indicator ◽  
Numerical Models ◽  
Measurement Techniques ◽  
Future Generations ◽  
Relative Speed ◽  
Experimental Campaign ◽  
Field Efficiency ◽  
And Performance ◽  
The One

Abstract The Ocean Cleanup Foundation is developing floating barrier systems to concentrate and extract buoyant plastic from the global accumulation zones. In that context, two cleanup systems have been designed, built and deployed in the Great Pacific Garbage Patch since 2018 to evaluate their performance in the field for which a large amount of data has been collected. This data serves to validate and calibrate numerical models that will be used to develop future generations of cleanup systems. The main performance indicator in scrutiny is the field efficiency which can be derived from on the one hand the barrier horizontal motion in terms of displacement and span heading and on the other hand the plastic transport around and inside the barrier. After a first part dedicated to the presentation of the experimental campaign carried out to evaluate the field efficiency of the second cleanup system, this second part is dedicated to the presentation of some results and analysis performed to evaluate the interception efficiency. This paper first focuses on the cross comparison of two measurement techniques to evaluate the barrier span length and heading, second the metocean models in terms of waves and wind are presented and compared against the available metocean measurements. Then, a multi-linear model is proposed to evaluate the barrier dynamics from the background metocean conditions and applied to the analysis of the barrier in the lifting bag configuration. Finally, the multi-linear model is compared to measured relative speed for all the drifter tests carried out in the campaign the whole test campaign.

Sign in / Sign up

Export Citation Format

Share Document