Preliminary 3D DEM Simulations on Ridge Keel Resistance on Ships
Published by (International Conference on Port and Ocean Engineering under Arctic Conditions)
Authors: Hanyang Gong, Arttu Polojärvi, Jukka Tuhkuri. Published June 13, 2017
Ice ridge resistance of ships operating on Arctic seas is of importance when estimating the ship traffic emissions and the efficiency of ship transport systems. Here we use 3D discrete element method (DEM) to simulate the interaction between a ridge keel and a ship. In this preliminary study, we will present results from simulations with various ridge keel lengths and accounting for the symmetry of the interaction scenario. We also study the effect of ridge keel widths on the keel resistance in our simulations.
Rigid dynamic performance simulation of an offshore pipeline plough
Published by (Ocean Engineering)
Authors: Wang Liquan, Gong Hanyang, Xing Xiaodong, Yuan Jinru. Published January 01, 2015
Offshore pipeline ploughs are used for laying pipelines in seabed trenches; these devices primarily consist of a plough body and skid and steering systems. Research on the virtual dynamic analysis of this system is essential for predicting the dynamic performance of the plough during trenching and steering. In this work, a 3-D rigid body dynamic simulation model is developed to investigate the performance of the simulated plough under different operating conditions. To verify this simulation model, an onshore field trenching study with a prototype plough was carried out. In terms of the tow force, the simulation results of the plough performance agree with the onshore field results and laboratory data within a certain range of simulation tolerance. We also present the effects of sandwaves and steering adjustment on the plough tow force. In addition, this paper addresses the development process and the dynamic results of the simulation model with a flexible towline. © 2014 Elsevier Ltd. All rights reserved.
Investigation on the dynamic performance of offshore pipeline plough
Published by (International Society of Offshore and Polar Engineers)
Authors: Gong Hanyang, Wang Liquan, Xing Xiaodong.. Published June 15, 2014
Analysis of the rigid body dynamic performance for offshore pipeline plough is important for structural OPP optimization, fatigue strength examination and hydraulic system design. This paper presents a method by which the soil resistance is numerically calculated by smoothed particle hydrodynamics method in ABAQUS. The towing force of the offshore pipeline plough and force in the skid arm are calculated by the rigid body dynamic model using soil resistance as input in ADAMS. This integrated simulation model is validated by the comparison of simulation and land test results. The simulation results show that the towing force at the beginning of trenching process declines as the water wave height increases when the wave has negative amplitude, but there is less impact during deeper trenching. The towing force increases nonlinearly as values of the soil technical parameters rise steadily. Additionally, the different fluid and soil parameters have less impact on the skid force. Copyright © 2014 by the International Society of Offshore and Polar Engineers (ISOPE).
Optimized Design of the Plow of a Submarine Plowing Trencher
Published by (Journal of Marine Science and Application)
Authors: Gong Hanyang, Yuan Ruhua, Xing Xiaodong, et.al. Published December 01, 2013
The plow of the submarine plowing trencher is one of the main functional mechanisms, and its optimization is very important. The design parameters play a very significant role in determining the requirements of the towing force of a vessel. A multi-objective genetic algorithm based on analytical models of the plow surface has been examined and applied in efforts to obtain optimal design of the plow. For a specific soil condition, the draft force and moldboard surface area which are the key parameters in the working process of the plow are optimized by finding the corresponding optimal values of the plow blade penetration angle and two surface angles of the main cutting blade of the plow. Parameters such as the moldboard side angle of deviation, moldboard lift angle, angular variation of the tangent line, and the spanning length are also analyzed with respect to the force of the moldboard surface along soil flow direction. Results show that the optimized plow has an improved plow performance. The draft forces of the main cutting blade and the moldboard are 10. 6% and 7%, respectively, less than the original design. The standard deviation of Gaussian curvature of moldboard is lowered by 64. 5%, which implies that the smoothness of the optimized moldboard surface is much greater than the original. © 2013 Harbin Engineering University and Springer-Verlag Berlin Heidelberg