Proceedings of the Thirty-second (2022) International Ocean and Polar Engineering Conference
Shanghai, China, June 5–10, 2022
Copyright © 2022 by the International Society of Offshore and Polar Engineers (ISOPE)
ISBN 978-1-880653-81-4; ISSN 1098-6189

www.isope.org

Research on the Influence of Sliding Piece Dislocation on Construction Parameters and Jet Water
Performance
Mingming Liu, Haifei Zhuang, Tao Guo and Jingzhao Hu

CCCC National Engineering Research Center of Dredging Technology and Equipment Co. Ltd.
Shanghai, China

ABSTRACTcenter and the hull suction center and has a certain impact on thedredging performance. In addition, the connection between the sliding
piece and the outlet pipeline of the jet water pump is sealed through therubber wrist. When it is misaligned, it may cause sealing failure, which
will directly affect the operation state of the jet water pump, and thenreduce the effect of flushing drag head and breaking the soil.

In order to ensure that the dredging performance of the trailing suction
hopper dredger will not be affected when the sliding piece is misaligned
and provide theoretical guidance for installation and maintenance ofsliding piece, taking a 4500 m3 trailing suction hopper dredger as anexample, the influence of different sliding piece dislocation distance on
the construction parameters and jet water performance are simulated
and analyzed. The simulation results of construction parameters
including suction vacuum and output at different dislocation show thatthe influence of dislocation on the suction vacuum and output can bealmost ignored; The simulation results of pressure of jet water system at
different dislocation show that the inlet pressure of jet water pipe anddrag head gradually decreases with the increase of dislocation. Andwhen the rubber wrist fail and the relative dislocation distance reaches
10mm, the inlet pressure of jet water pipe and drag head decreases by
24.7% and 21.8% respectively compared with that without leakage; The
inlet flow of jet water pipe increases and the inlet flow of drag headdecreases with the increase of dislocation. When the rubber wrist failand the relative dislocation distance is 10mm, the inlet flow of jet water
pipe increases by 35.1% and the inlet flow of drag head decreases by
11.6%; When the leakage increases to a certain extent, the speed of jetwater pump will decrease linearly.

At present, the method of numerical simulation has been widely used in
the dredging industry to study complex fluid motion. Zhang(2018) usedsolid-liquid two-phase flow to simulate the flow fields of the cutter
suction dredger cutting system, the research results are helpful to better
understand the particle flow characteristics, it provides theoreticalguidance for related system design and operation parameter
optimization; Luo(2020) analyzed the resistance characteristics of thetrailing suction hopper dredger hull at various speeds by establishing thenumerical model. The calculated results are in good agreement with theexperimental results; Shen(2019) used numerical pool technology toanalyze the drag resistance characteristics of the drag arm pipe structurewith underwater pump, and reasonably evaluated and predicted the dragresistance performance of the drag arm pipe under various working
conditions; Zheng(2017) analyzed the internal flow field of the draghead, and on this basis, modified and optimized the drag head to reduce
the generation of vortex and flow resistance of the drag head. Since
there is no theoretical calculation method for the resistance of thedredge delivery pipe and the pipe of the jet water pump when the sliding
piece is misaligned, our project team plans to use the method ofnumerical simulation to study the matching relationship between thedredge pump, the jet water pump and the pipeline, and then calculate
and analyze the influence of the dislocation between the sliding pieceand the hull side suction on the construction parameters and the jetwater performance, so as to provide theoretical guidance for the
structural design, installation and maintenance of the sliding piece.

KEY WORDS: Sliding piece; numerical simulation; jet water;
trailing suction hopper dredger.
INTRODUCTION
As an important part of the delivery system of the trailing suction
hopper dredger, the sliding piece can be used to connect the drag arm
pipe and the hull side suction on the one hand, and to connect the highpressure flushing pipe with the jet water pump outlet pipeline on theother hand. Its cooperation with the hull side suction and the jet water
pump outlet pipeline directly affects the operation state of the dredger.
In the process of dredging, the sliding piece tends to move downward
and towards the stern due to the wear between the wear ring and thesuction retaining ring and the wear between the adjusting wedge and thehull rigid body wedge and the wear between the wear block and theguide rail, which result in a certain dislocation between the sliding piece

NUMERICAL SCHEME
Dredge Delivery System
Computational Model
The function of dredge delivery system is to convey the slurry dredged

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