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Along with developing high-speed craft technology, the planing hull is growing with modifications for better performance. One such technology is stepped hull, both single and double. Planing hull with steps allows the boat to run at a relatively low drag-lift ratio with lower frictional resistance due to reduced wetted area. In this study, the hull...
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... two steps are varied based on the í µí±¥/í µí°¿ value measured from the transom. The length of these variations is presented in Table 2 and illustrated in Fig. 3. The shifting of these steps impacts changes in the displacement (∆) value. ...Similar publications
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... There are several methods to enhance the energy efficiency of ships (Molland et al., 2014;Wang and Lutsey, 2014). Firstly, this can be achieved by designing or modifying the hull shape to be more optimal, which, in turn, can improve the overall performance of the ship (Choi, 2015;Hakim et al., 2023d;Seok et al., 2019;Tran et al., 2022;Trimulyono et al., 2023). Secondly, determining more optimal operational patterns by considering routes in relation to weather conditions can optimize energy consumption (Taskar and Andersen, 2020;Zis et al., 2020). ...
This study investigates the crucial role of surface roughness caused by biofouling in contributing to increased drag in fast planing vessels. Through rigorous computational fluid dynamics (CFD) simulations using a full-scale reference hull, the impact of surface roughness on planing hull performance is examined. The results show that heavy slime roughness on the hull surface causes a significant increase in total resistance, ranging from 10% at low speeds to 80% at high speeds. Skin friction was identified as the most affected component of resistance, with additional changes in residual resistance. Although the change in residual resistance is relatively small, they give rise to dynamic phenomena such as variations in pressure distribution, wave elevation, and wave making formation. The study also explores the influence of surface roughness on dynamic lift forces, observing an increase in upward friction forces but ultimately concludes that overall hull performance was hampered due to the disproportionately higher increase in resistance caused by roughness (biofouling). Changes in dynamic trim, dynamic sinkage, and dynamic wetted surface area due to this roughness are also discussed.
... Maritime Research Institute Netherlands (MARIN) is one organization that provides general ship data such as KVLCC1 & 2, KCS, and DTMB 5415 using the FRMT method. Apart from using the FRMT method, the CFD method to predict ship manoeuvres is starting to develop over time [3,4,5,6]. This approach can simulate the condition of a ship when manoeuvring according to its original requirements but requires quite a large number of resources to complete the simulation. ...
... ( ⁄ ) ⁄ is the ratio of the coefficient Cb which represents the level of hull contrast to L/B and represents the unique characteristics of the hull [3]. Figure 7 and Figure 8 show the relationship between the twenty-six ship's data (thirteen ships from Yoshimura data and thirteen ships from new container data) linear hydrodynamic coefficients (15) and the ship's parameters. ...
International Maritime Organization (IMO) provided manoeuvrability standards for all ships above 100 m to ensure the ship's safety and surroundings. In the preliminary design stage, one way to ensure a ship's manoeuvrability under IMO standards is to use empirical methods that are cheaper and less time-consuming than model tests. Empirical methods used analysis regression to develop their formula from the model test result database, and their formula depends on ship hull parameters and dimension ratios such as , , , and . However, the database of the existing empirical formulas is limited to small-medium merchant ships and fishing vessels, as consequences for larger ships are inaccurate and have a significant error in predicting ship manoeuvres. This study modified the existing empirical formulas by adding specified ship data into the existing database and analyzing the accuracy of predicting ship manoeuvres using the Maneuvering Modelling Group (MMG) model. We verify by adding the selected ship data into the existing database, which shows improvement in predicting ship manoeuvres. The modified formulas show improvement by only giving 5% RMSE of tactical diameter and 3% RMSE of ship advance in turning manoeuvre, and this is a 78% overall improvement in predicting the turning motion of ultra-large container ships compared to previous formulas. The quantitative and qualitative produce better estimation result that indicates the right track to derive the empirical formulas for Ultra-Large Container ships.
... External environment, ship shape, material characteristics, navigation attitude, and water molecular characteristics have a great influence on the calculation or prediction of ship resistance [6,7]. In order to accurately predict the influence of heterogeneous hull roughness on ship resistance, Roberto et al. [8] conducted a series of CFD simulations on the hull model of a KRISO container ship (KSC) based on the improved wall function. ...
Ship resistance has a very important value in the determination of ship power and the design of emission standards. In this paper, a ship resistance model with different displacement, speed, and attachment under the condition of a fixed scale ratio is tested by means of experimental research, which is used to analyze the change law of ship resistance under the condition of a single factor. The coupling effects of multiple factors on the actual ship power are studied after the establishment of a mathematical relationship between the actual ship power and resistance on the basis of the response surface method. The research results show that: (1) there is an obvious positive correlation between ship resistance and speed, which matches the change law of the exponential equation. Compared with ship appendages, displacement and speed have the greatest influence on resistance. (2) According to the correlation analysis, the maximum correlation coefficient between ship speed/resistance and power is 0.99, and the correlation coefficients between displacement/resistance and power are 0.93 and 0.88, respectively. However, the correlation coefficients between ship appendages and resistance and power are only 0.23 and 0.14, respectively. (3) The actual ship power and speed, displacement, and appendages form a quadratic polynomial relationship. The multi-factor interaction analysis results show that speed and displacement have the greatest influence on the actual ship power. The research results have a certain guiding significance for ship design.
... The current situation is the main focus of efforts to stop climate change and global warming 15,16,50) , so reducing emissions on HSMVs is a challenge. Several methods to reduce emissions on board include 9,51) : optimization of hull shape [52][53][54][55] , weather routing 56,57) , maintaining a clean hull from biofouling [58][59][60][61][62][63][64][65][66][67] use of more environmentally friendly fuels [68][69][70][71][72] , optimization of propellers 73,74) , using additional environmentally friendly energy resources 75) . ...
