Voyage optimization using dynamic programming with initial quadtree based route
Abstract This research proposes an integrated voyage optimization algorithm that combines quadtree graph generation, visibility graph simplification, Dijkstra’s algorithm, and a 3D dynamic programming (3DDP) method. This approach enables the determination of a minimum distance initial reference route and the creation of a 2D navigational graph for efficient route optimization. We effectively store and process […]
Stable LBM schemes for acoustic scaling simulations under high Reynolds to Mach ratio: Introduction to the DM-TS operator
Abstract Hydroacoustic analyses using direct methods are challenging in the field of computational physics. To date, hybrid methods are an alternative approach adopted for performing hydroacoustic analysis, although it demonstrates clear limitations in analyzing nonlinear turbulent noise. The lattice Boltzmann method (LBM) provides a solution to address the limitations of the hybrid method and is frequently applied […]
Capturing downstream wake of a marine current turbine by URANS and SST-IDDES
Abstract Unsteady Reynolds-Averaged Navier–Stokes (URANS) and SST-based improved delayed detached eddy simulation (SST-IDDES) are used to compare the performance, flow field characteristics, and downstream turbine installation distance of a Marine Current Turbine (MCT). The flow domain is discretized with unstructured tetrahedral mesh using the Fluent 2020R1 meshing tool, sliding mesh method used for turbine rotation. […]
Analysis of noise attenuation for offshore platform silencer in duct with flow
Abstract Recently, the NORSOK standards, which regulate noise and vibration on offshore platforms, were strengthened by prohibiting the use of glass wool for environmental and safety reasons. In addition, the use of sound-absorbing materials in panels and silencers was prohibited. Therefore, developing a silencer that does not use sound-absorbing materials is necessary. In this study, […]
Numerical investigation of bending-torsion coupling effect on aeroacoustic noise of a flexible unmanned aerial vehicle propeller
Abstract The recent explosion in interest into the use of UAVs for a wide range of commercial applications has also raised awareness of the issue of noise coming from UAVs. This paper introduces a method for predicting the aeroacoustic noise of a flexible UAV propeller while considering bending–torsion coupling. Numerical simulations of a flexible UAV […]
Design of cascade refrigerant process utilizing CO2 and NH3 to remove volatile organic compounds
Abstract Volatile Organic Compounds (VOC) are organic substances that evaporate from crude oil. About 0.08–0.15 % of the crude oil loaded into the ship is released as VOCs, which indicates that 50–200 tons of VOC are generated per loading. The recovery of VOCs generated by crude oil loading is essential to avoid any environmental issues. In […]
Effect of electrolyte solubility and column inclination on the performance of monoethylene glycol regeneration process
Abstract In this study, the solubilities of potassium-chloride (KCl) in aqueous monoethylene glycol (MEG) solution and the vapour pressure of aqueous MEG solution containing KCl were investigated. A thermodynamic model was modified based on the data obtained to predict the solubilities of KCl, which was then applied to optimize the MEG regeneration process that is […]
Comparative analysis of cryogenic distillation and chemical absorption for carbon capture in integrated natural gas liquefaction processes
Abstract Compared with the widely used chemical absorption, cryogenic distillation has a lower thermal energy consumption and smaller footprint of the carbon capture unit. However, the power consumption of cryogenic distillation is higher. This study aims to use the azeotropic properties of ethane-CO2 mixtures to achieve CO2 capture by cryogenic distillation for cleaner LNG production. A single mixed refrigerant LNG process integrated with cryogenic distillation (CD-LNG) or chemical absorption […]
An experimental study on riser hand-over operation between an installation vessel and an FPSO in regular waves
Abstract Experimental and numerical studies were performed on the hand-over operation of a riser between an installation vessel and an FPSO. A series of model tests were conducted in the Ocean Engineering Basin of KRISO. In the model test, a riser truncation model was introduced considering the limited depth of the basin and pit diameter. In […]
Integration of long-term planning and mid-term scheduling of shipbuilding
Abstract A shipyard’s production plan has a hierarchical structure comprising a long-term plan and a mid-term or short-term plan. The mid-term schedule is established based on the major schedules of the long-term plan. However, in the long-term planning stage, the mid-term schedule is not considered owing to timing discrepancies and the lack of data. Therefore, […]
