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 Showing 1 - 57 of 57 Journals sorted alphabetically Air, Soil & Water Research       (Followers: 6) altlastenforum Baden-Württemberg e.V., Schriftenreihe       (Followers: 3) American Journal of Fluid Dynamics       (Followers: 48) American Water Works Association       (Followers: 23) Annual Review of Fluid Mechanics       (Followers: 51) Annual Review of Marine Science       (Followers: 12) Archives of Hydro-Engineering and Environmental Mechanics       (Followers: 1) Asian Journal of Water, Environment and Pollution       (Followers: 10) AWWA Water Science       (Followers: 1) Bulletin of Marine Science       (Followers: 8) Computers & Fluids       (Followers: 30) Development and Applications of Oceanic Engineering       (Followers: 2) Discover Water       (Followers: 1) Drinking Water Engineering and Science (DWES)       (Followers: 7) Ecohydrology & Hydrobiology       (Followers: 4) Experimental Thermal and Fluid Science       (Followers: 32) Hydroécologie Appliquée Hydrology: Current Research       (Followers: 9) Hydrometallurgy       (Followers: 11) Ingeniería del agua Ingeniería Hidráulica y Ambiental International Journal of Fluid Power       (Followers: 4) International Journal of Hydraulic Engineering       (Followers: 8) International Journal of Hydrology Science and Technology       (Followers: 6) International Journal of Hydromechatronics International Journal of Soil, Sediment and Water       (Followers: 4) ISH Journal of Hydraulic Engineering Journal of Applied Water Engineering and Research Journal of Coastal and Hydraulic Structures (JCHS)       (Followers: 2) Journal of Coastal and Riverine Flood Risk (JCRFR)       (Followers: 1) Journal of Ecohydraulics       (Followers: 1) Journal of Hydraulic Engineering       (Followers: 27) Journal of Hydraulic Research       (Followers: 5) Journal of Hydrodynamics       (Followers: 2) Journal of Hydrologic Engineering       (Followers: 40) Journal of Hydrology and Hydromechanics       (Followers: 4) Journal of Marine Science and Application       (Followers: 2) Journal of Ocean University of China (English Edition)       (Followers: 1) Journal of the Marine Biological Association of the UK       (Followers: 23) Journal of Water Process Engineering       (Followers: 3) Journal of Water Resources Planning and Management       (Followers: 65) Journal of Waterway Port Coastal and Ocean Engineering       (Followers: 7) LARHYSS Journal LHB Hydroscience Journal Limnology and Oceanography: Fluids and Environments       (Followers: 5) Marine Genomics       (Followers: 1) Marine Science       (Followers: 4) Marine Structures       (Followers: 4) Maritime Studies       (Followers: 12) Navigation       (Followers: 266) Proceedings of the Institution of Civil Engineers - Water Management       (Followers: 7) Regional Studies in Marine Science       (Followers: 1) Revista de Ingeniería Hidráulica y Ambiental Revista Ingeniería Agrícola Ribagua : Revista Iberoamericana del Agua Water SA       (Followers: 2) Water Science and Engineering       (Followers: 13)
Similar Journals
 Journal of Marine Science and ApplicationJournal Prestige (SJR): 0.288 Citation Impact (citeScore): 1Number of Followers: 2      Hybrid journal (It can contain Open Access articles) ISSN (Print) 1993-5048 - ISSN (Online) 1671-9433 Published by Springer-Verlag  [2469 journals]
• Oblique Wave Scattering Problems Involving Vertical Porous Membranes

Abstract: Abstract Oblique surface waves incident on a fixed vertical porous membrane of various geometric configurations is analyzed here. The mixed boundary value problem is modified into easily resolvable problems by using a connection. These problems are reduced to that of solving a couple of integral equations. These integral equations are solved by a one-term or a two-term Galerkin method. The method involves a basis functions consists of simple polynomials multiplied with a suitable weight functions induced by the barrier. Coefficient of reflection and total wave energy are numerically evaluated and analyzed against various wave parameters. Enhanced reflection is found for all the four barrier configurations.
PubDate: 2022-03-01

• Miller Cycle with Early Intake Valve Closing in Marine Medium-Speed Diesel
Engines

Abstract: Abstract In this study, a one-dimensional simulation was performed to evaluate the performance of in-cylinder combustion to control NOx emissions on a four-stroke, six-cylinder marine medium-speed diesel engine. Reducing the combustion temperature is an important in-cylinder measure to decrease NOx emissions of marine diesel engines. The Miller cycle is an effective method used to reduce the maximum combustion temperature in a cylinder and accordingly decrease NOx emissions. Therefore, the authors of this study designed seven different early intake valve closing (EIVC) Miller cycles for the original engine, and analyzed the cycle effects on combustions and emissions in high-load conditions. The results indicate that the temperature in the cylinder was significantly reduced, whereas fuel consumption was almost unchanged. When the IVC was properly advanced, the ignition delay period increased and the premixed combustion accelerated, but the in-cylinder average pressure, temperature and NOx emissions in the cylinder were lower than the original engine. However, closing the intake valve too early led to high fuel consumption. In addition, the NOx emissions, in-cylinder temperature, and heat release rate remarkably increased. Therefore, the optimal timing of the EIVC varied with different loads. The higher the load was, the earlier the best advance angle appeared. Therefore, the Miller cycle is an effective method for in-engine NOx purification and does not entail significant cost.
PubDate: 2022-03-01

• Wave Scattering by a Submerged Sphere in Three-Layer Fluid

Abstract: Abstract Using linear water wave theory, three-dimensional problems concerning the interaction of waves with spherical structures in a fluid which contains a three-layer fluid consisting of a layer of finite depth bounded above by freshwater of finite depth with free surface and below by an infinite layer of water of greater density are considered. In such a situation time-harmonic waves with a given frequency can propagate with three wavenumbers. The sphere is submerged in either of the three layers. Each problem is reduced to an infinite system of linear equations by employing the method of multipoles and the system of equations is solved numerically by standard technique. The hydrodynamic forces (vertical and horizontal forces) are obtained and depicted graphically against the wavenumber. When the density ratio of the upper and middle layer is made to approximately one, curves for vertical and horizontal forces almost coincide with the corresponding curves for the case of a two-layer fluid with a free surface. This means that in the limit, the density ratio of the upper and middle layer goes to approximately one, the solution agrees with the solution for the case of a two-layer fluid with a free surface.
PubDate: 2022-03-01

• Two-Layer Path Planner for AUVs Based on the Improved AAF-RRT Algorithm

Abstract: Abstract As autonomous underwater vehicles (AUVs) merely adopt the inductive obstacle avoidance mechanism to avoid collisions with underwater obstacles, path planners for underwater robots should consider the poor search efficiency and inadequate collision-avoidance ability. To overcome these problems, a specific two-player path planner based on an improved algorithm is designed. First, by combing the artificial attractive field (AAF) of artificial potential field (APF) approach with the random rapidly exploring tree (RRT) algorithm, an improved AAF-RRT algorithm with a changing attractive force proportional to the Euler distance between the point to be extended and the goal point is proposed. Second, a two-layer path planner is designed with path smoothing, which combines global planning and local planning. Finally, as verified by the simulations, the improved AAF-RRT algorithm has the strongest searching ability and the ability to cross the narrow passage among the studied three algorithms, which are the basic RRT algorithm, the common AAF-RRT algorithm, and the improved AAF-RRT algorithm. Moreover, the two-layer path planner can plan a global and optimal path for AUVs if a sudden obstacle is added to the simulation environment.
PubDate: 2022-03-01

• A Coupled ISPH-TLSPH Method for Simulating Fluid-Elastic Structure
Interaction Problems

Abstract: Abstract A fully Lagrangian algorithm for numerical simulation of fluid-elastic structure interaction (FSI) problems is developed based on the Smoothed Particle Hydrodynamics (SPH) method. The developed method corresponds to incompressible fluid flows and elastic structures. Divergence-free (projection based) incompressible SPH (ISPH) is used for the fluid phase, while the equations of motion for structural dynamics are solved using Total Lagrangian SPH (TLSPH) method. The temporal pressure noise can occur at the free surface and fluid-solid interfaces due to errors associated with the truncated kernels. A FSI particle shifting scheme is implemented to produce sufficiently homogeneous particle distributions to enable stable, accurate, converged solutions without noise in the pressure field. The coupled algorithm, with the addition of proposed particle shifting scheme, is able to provide the possibility of simultaneous integration of governing equations for all particles, regardless of their material type. This remedy without need for tuning a new parameter, resolves the unphysical discontinuity beneath the interface of fluid-solid media. The coupled ISPH-TLSPH scheme is used to simulate several benchmark test cases of hydro-elastic problems. The method is validated by comparison of the presented results with experiments and numerical simulations from other researchers.
PubDate: 2022-03-01

• Numerical Simulation of the Hydrodynamic Characteristics of the Porous
I-type Composite Breakwater

Abstract: Abstract Based on the three-dimensional Reynolds-averaged Navier-Stokes equation with the closure of renormalization group k−ε turbulence model and volume of fluid method, a wave-breakwater interaction numerical flume was developed to examine the wave-structure interaction of the porous I-type composite (PITC) breakwater. The transmission and reflection coefficients of the breakwater at different wave steepness H/L are quantitatively analyzed, and the wave-dissipating performance of the breakwater is compared. By changing the submerged depth of the breakwater, the velocity field, and vorticity field in the wave propagation process are analyzed, and the optimal working water depth of the new breakwater is explored. The results show that the vertical wave force on the PITC breakwater is greater than the horizontal wave force. In addition, during the wave dissipation process, the transverse baffle provided by the new breakwater destroys the trajectory of the water particle. In the interior of the wave-breaking chamber, the water that enters from the gap of the permeable plate mixes with the water entering through the bottom hole. The turbulence created by this process further dissipates the wave energy. The relative submergence depth of h/d has a great influence on the hydrodynamic characteristics. When the relative depth is large, most of the wave energy enters the breakwater, the wave energy dissipation of the breakwater is large, and the wave-absorbing effect is good. These research results provide important referential data for the study of permeable plate breakwaters.
PubDate: 2022-03-01

• Submerged Geosynthetic Reef as Shore Protection Measure for Islands

Abstract: Abstract The Sagar Island, located north of the Bay of Bengal, intercepts the flow in the Hoogly estuary that comprises a network of several estuarine distributaries and creeks, which is considered to be one of the largest estuarine systems in the world. The Hooghly River experiences a tidal range in the order of about 4 m, due to which the tide-generated currents drive the sediments which are continuously set in motion. The temple, Kapil Muni (21°38′15.35″N, 88°4′30.56″E) is located on the south-western side of Sagar Island, where an annual religious festival and rituals with about a million pilgrims is conducted. The pertinent erosion problem at a rate of about 5 m/year is prevalent at the site has considerably reduced the beach width, thereby, resulting in reduced space for religious as well as recreational activities along the coast. A novel cross-section for the proposed submerged reef using geosynthetic materials is designed considering the different site-specific, environmental, and socio-economic conditions. The submerged reef can effectively be devised to redistribute the current circulation pattern and trap the sediment for beach restoration. The performance of such a structure depends on its geometrical and structural characteristics, the location of the reef (i. e.) the water depth at the toe, distance from the coastline, wave-structure interaction, sediment transport and local morpho dynamics. The aforesaid criteria were optimized using a numerical model which predicted the average residual velocity in the site to be in the order of about 1 m/s. Owing to logistical constraints geosynthetic materials had to be employed. The detailed design of such a system arrived through numerical modelling and field measurements are presented and discussed in this paper.
PubDate: 2022-03-01

• Ship Roll Analysis Using CFD-Derived Roll Damping: Numerical and
Experimental Study

Abstract: Abstract This study investigates the roll decay of a fishing vessel by experiments and computational fluid dynamics (CFD) simulations. A fishing vessel roll decay is tested experimentally for different initial roll angles. The roll decay is also simulated numerically by CFD simulations and is validated against the experimental results. It shows that the roll damping could be obtained by CFD with high level of accuracy. The linear and nonlinear damping terms are extracted from the CFD roll decay results and are used in a potential-based solver. In this way we are using a hybrid solver that benefits the accuracy of the CFD results in terms of roll damping estimation and the fast computations of the potential-based solver at the same time. This hybrid method is used for reproducing the free roll decays at Fn=0 and also in analyzing some cases in waves. The experiments, CFD and the hybrid parts are described in detail. It is shown that the suggested method is capable of doing the simulations in a very short time with high level of accuracy. This strategy could be used for many seakeeping analyses.
PubDate: 2022-03-01

• Numerical Study of the Ice Breaking Resistance of the Icebreaker in the
Yellow River Through Smoothed-Particle Hydrodynamics

Abstract: Abstract A ship — ice — water interaction model is established using smoothed-particle hydrodynamics (SPH) to predict the ice breaking resistance of the icebreaker in the Yellow River effectively. This method includes the numerical process of the constitutive equation, yield criterion, and the coupling model in SPH. The ice breaking resistance is determined under different conditions. The numerical results of the ice breaking resistance agree with the empirical formula results. Results show that the prediction accuracy of ice resistance is less than 17.6% compared with the empirical formula in the level ice. The method can also be extended to predict the floe motion and ice breaking resistance in actual river channels. The validation against the empirical formula indicates that the proposed ship — ice — water SPH method can predict the ice breaking resistance of icebreakers in actual rivers effectively. The predicted ice breaking resistance is analyzed under different conditions. The ice breaking resistance increases with increasing bending strength and ice thickness, and the latter is the most important factor influencing ice resistance.
PubDate: 2022-03-01

• Wave Energy Potential Analysis in the Casablanca-Mohammedia Coastal Area
(Morocco)

Abstract: Abstract In the last two decades, the exploitation of marine renewable energies (70% of the globe is made up of oceans), especially wave energy, has attracted great interest, not only for their high potential, but also for their high energy density. The development of wave energy is suitable for countries or regions with extensive coastline and high waves approaching the shore. This paper focuses on the study of wave potential and wave energy distribution in the Casablanca-Mohammedia nearshore area (Moroccan Atlantic coast) in order to identify prospective wave energy hotspots. To achieve this purpose, the offshore wave potential was firstly estimated from a 20 years wave data provided by ECMWF (European Center for Medium range Weather Forecasts). In the second step, a numerical modeling of the wave propagation in the study area was performed using the SWAN model jointly with WAVEWATCHIII. The performance of the model to simulate accurately the wave field was evaluated in a real situation characterized by large waves. The model then was applied to determine the patterns of wave field in the Casablanca-Mohammedia nearshore area for a typical wave conditions (winter, summer and storm). The results of this study show the abundance of wave energy in the region with an average annual wave potential of about 22 kW/m. A seasonal variability of the wave resource was demonstrated, with values five times higher in winter than in summer. In addition, a major hotspot site was identified that should be considered when studying WEC implementation. This hotspot is located at the southern edge of the Casablanca-Mohammedia coast, near the coastal area of Sidi Rahal.
PubDate: 2022-03-01

• Simulation Study of Disastrous Waves Along Indonesian Offshore and Coast
Under Roaring Forties and Tropical Cyclones

Abstract: Abstract Indonesian offshore and coastal areas are vulnerable to swells from Roaring Forties and cyclone disasters. However, the understanding of the characteristics and propagation mechanisms of local disastrous waves is insufficient, posing a threat to the construction, maintenance, and protection of coastal structures. This study establishes a multiple nested wave model based on the third-generation wave model WAVEWATCH III. This model includes sole forcing of Roaring Forties and combined forcing of Roaring Forties and cyclone Ernie to simulate the influence of disastrous waves under the Roaring Forties and tropical cyclones in the Indonesian offshore zone and coasts. The following results are obtained. The Indonesian offshore is prevailed by relatively stable southern to southwestern dominant swells and small wind waves under the impacts of the Roaring Forties without cyclone winds. Long propagating swells originated from the Roaring Forties dominate in nearshore coastal waters with deformed directions and strength because of the shoaling effect.
PubDate: 2022-03-01

• Optimization of a Dual-Baffled Rectangular Tank Against the Sloshing
Phenomenon

Abstract: Abstract A dual-baffled rectangular tank with different configurations is proposed to reduce the sloshing effect, and design optimization is conducted through numerical simulations with open-source software, namely OpenFOAM, based on the computational fluid dynamic model. A series of physical experiments in the dual-baffled rectangular tank is performed for model validation and design optimization with the measured water surface elevation distributions along the tank. The optimization uses the calculated maximum horizontal force exerted on the tank and entropy generation (EG) as the criterion. Results show that the dual-baffle configuration positioned at the tank center is more effective in reducing the sloshing than that of the single baffle when the relative baffle height and initial water depth ratio (Hb/Hw, where Hb and Hw represent baffle height and static water depth, respectively) are larger than 0.5. However, such an effect then diminishes when the ratio is larger than 0.75. The effect of the dual-baffle configuration on the sway motion under the condition of different motion amplitudes and frequencies is also evaluated. The results show that the reduction in the maximum horizontal force is almost the same for dual- and single-baffled configurations and reaches the minimum when the sway motion amplitude is near 0.03 m. The dual-baffled configuration for the angular frequency of the sway motion is more effective than the single-baffled in reducing the sloshing at the low angular frequencies but is only less effective at high angular frequencies. Furthermore, the optimal baffle inclination angle is 85° when the inclined straight and curved baffles are used, and curved baffles can successfully decrease the horizontal force exerted on the tank and EG.
PubDate: 2022-03-01

• Parametric Hull Form Optimization of Containerships for Minimum Resistance
in Calm Water and in Waves

Abstract: Abstract This paper described the process of generating the optimal parametric hull shape with a fully parametric modeling method for three containerships of different sizes. The newly created parametric ship hull was applied to another ship with a similar shape, which greatly saved time cost. A process of selecting design variables was developed, and during this process, the influence of these variables on calm water resistance was analyzed. After we obtained the optimal hulls, the wave added resistance and motions of original hulls and optimal hulls in regular head waves were analyzed and compared with experimental results. Computations of the flow around the hulls were obtained from a validated nonlinear potential flow boundary element method. Using the multi-objective optimization algorithm, surrogate-based global optimization (SBGO) reduced the computational effort. Compared with the original hull, wave resistance of the optimal hulls was significantly reduced for the two larger ships at Froude numbers corresponding to their design speeds. Optimizing the hull of the containerships slightly reduced their wave added resistance and total resistance in regular head waves, while optimization of their hulls hardly affected wave-induced motions.
PubDate: 2022-01-17
DOI: 10.1007/s11804-021-00243-w

• Application of the Latching Control System on the Power Performance of a
Wave Energy Converter Characterized by Gearbox, Flywheel, and Electrical
Generator

Abstract: Abstract The latching control represents an attractive alternative to increase the power absorption of wave energy converters (WECs) by tuning the phase of oscillator velocity to the wave excitation phase. However, increasing the amplitude of motion of the floating body is not the only challenge to obtain a good performance of the WEC. It also depends on the efficiency of the power take-off system (PTO). This study aims to address the actual power performance and operation of a heaving point absorber with a direct mechanical drive PTO system controlled by latching. The PTO characteristics, such as the gear ratio, the flywheel inertia, and the electric generator, are analyzed in the WEC performance. Three cylindrical point absorbers are also considered in the present study. A wave-to-wire model is developed to simulate the coupled hydro-electro-mechanical system in regular waves. The wave energy converter (WEC) performance is analyzed using the potential linear theory but considering the viscous damping effect according to the Morison equation to avoid the overestimated responses of the linear theory near resonance when the latching control system is applied. The latching control system increases the mean power. However, the increase is not significant if the parameters that characterize the WEC provide a considerable mean power. The performance of the proposed mechanical power take-off depends on the gear ratio and flywheel. However, the gear ratio shows a more significant influence than the flywheel inertia. The operating range of the generator and the diameter/draft ratio of the buoy also influence the PTO performance.
PubDate: 2022-01-03
DOI: 10.1007/s11804-021-00238-7

• Experimental Study of a Sphere Bouncing on the Water

Abstract: Abstract In this paper, the flow physics and impact dynamics of a sphere bouncing on a water surface are studied experimentally. During the experiments, high-speed camera photography techniques are used to capture the cavity and free surface evolution when the sphere impacts and skips on the water surface. The influences of the impact velocity (v1) and impact angle (θ1) of the sphere on the bouncing flow physics are also investigated, including the cavitation evolution, motion characteristics, and bounding law. Regulations for the relationship between v1 and θ1 to judge whether the sphere can bounce on the water surface are presented and analyzed by summarizing a large amount of experimental data. In addition, the effect of θ1 on the energy loss of the sphere is also analyzed and discussed. The experiment results show that there is a fitted curve of $${v}_{1}=17.5{\theta }_{1}-45.5$$ determining the relationship between the critical initial velocity and angle whether the sphere bounces on the water surface.
PubDate: 2022-01-01
DOI: 10.1007/s11804-021-00236-9

• Joint Offshore Wind and Wave Energy Resources in the Caribbean Sea

Abstract: Abstract Complementarities between wind and wave energies have many significant advantages that are unavailable with the sole deployment of either. Using all available wind speed, significant wave height, and wave period buoy observations over a 10-year period (i.e., 2009–2019), colocated wind and wave energy resources are estimated. Although buoy records are imperfect, results show that the inner Caribbean Sea (CS) under the influence of the Caribbean low-level jet has the highest wind energy resource at ~ 1500 W/m2, followed by the outer CS at ~ 600 W/m2 and Atlantic Ocean (AO) at ~ 550–600 W/m2 at a 100 m height. Wave energy was most abundant in the AO at 14 kW/m, followed by the inner CS at 13 kW/m and outer CS at 5 kW/m. The average and dominant wave energies can reach a maximum of 10 and 14 kW/m, respectively. Asymmetry between wind and wave energy resources is observed in the AO, where wave energy is higher than the low wind speed/energy would suggest. Swell is responsible for this discrepancy; thus, it must be considered not only for wave energy extraction but also for wind turbine fatigue, stability, and power extraction efficiency.
PubDate: 2021-12-09
DOI: 10.1007/s11804-021-00231-0

• Evaluation of the Safe and Failure Zones of Mooring and Riser Systems in a
CALM Oil Terminal

Abstract: Abstract The mooring and riser system is the most critical part of an offshore oil terminal. Traditionally, these two parts are designed separately without considering the nonlinear interaction between them. Thus, the present paper aims to develop an integrated design process for riser systems with a lazy-S configuration and mooring systems in the offshore catenary anchor leg mooring (CALM) oil terminal. One of the important criteria considered in this integrated design is the offset diagram and safe operation zone (SAFOP) related to the mooring system and the riser, respectively. These two diagrams are obtained separately by different analyses; therefore, codes or standards are available separately for two components. In this methodology, the diagrams of both risers and mooring lines are incorporated into a single spiral, thus identifying the safe and failure zones of risers and the mooring lines of the oil terminal. This, in turn, leads to substantial benefits in terms of overall system response, cost reduction, and safety to the offshore oil terminal. To implement this process, three different riser lengths with the lazy-S configuration are considered at three different sea depths at the terminal installation site. For each condition, the integrated design of the mooring system and riser is executed according to the derived procedure. Then, coupled dynamic models, wherein both buoys and hoses are included, are developed using OrcaFlex. Results show that the criteria of the relevant regulations are not satisfied by reducing the length of the riser relative to the designed size. Further, as water depth increases, this type of riser configuration shows good coupled performance while interacting with the mooring system. In the cross offset mode, the maximum margin is created between the offset diagram and the SAFOP diagram, while the most critical dynamic response of the tanker and terminal system occurs in the near and far modes. Therefore, with this method, the best position for the riser direction with the tanker direction is 90° in the best case.
PubDate: 2021-12-05
DOI: 10.1007/s11804-021-00240-z

• Correction to: Buckling Properties of a Subsea Function Chamber for
Oil/Gas Processing in Deep Waters

PubDate: 2021-12-02
DOI: 10.1007/s11804-021-00233-y

• Correction to: A Mathematical Model of a Ship with Wings Propelled by
Waves

PubDate: 2021-10-11
DOI: 10.1007/s11804-021-00229-8

• A Mathematical Model of a Ship with Wings Propelled by Waves

Abstract: Abstract This paper discusses mathematical modeling of a ship equipped with energy-saving wing devices. Therewith, the ship is mathematically represented by an elongated hull with high-aspect-ratio wings mounted near its bow and stern. Equations, describing ship motions in regular oncoming waves, are written in the spirit of strip theory with account of inertial and damping influence of energy-saving wing elements with the use of linear expansion of wing-related forces with respect to heave and pitch perturbations. This approach readily yields fast numerical solutions for the propulsion of a ship with wings in waves. The latter solutions are then used as an input for calculation of thrust on wing elements on the basis of classical unsteady foil theories corrected for finite aspect ratio. To evaluate speed of the ship in the modes which allow cruising exclusively by wave power, it is hypothetically assumed that in this case, the wave-generated thrust on the wings equals total drag of the ship-plus-wings system, the latter being defined as a sum of its viscous, wave-making, induced (for wing elements) and added-wave components. Excepting the added-wave term and wings’ contributions, the total drag is calculated herein by Holtrop method whereas added-wave resistance is evaluated with Beukelman-Gerritsma formula involving kinematic parameters of heaving and pitching motions of the ship calculated both without and with account of the wings. Also discussed in the paper is a decrease of added wave resistance for a ship with wings as compared to that of ship without wings. Finally, the energy efficiency design index (EEDI) introduced by the International Maritime Organization (IMO) is discussed for representative sea conditions as a measure of ship environmental friendliness.
PubDate: 2021-09-01
DOI: 10.1007/s11804-021-00221-2

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