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Journal of Marine Science and Application
Journal Prestige (SJR): 0.288  Citation Impact (citeScore): 1 Number of Followers: 3  Hybrid journal (It can contain Open Access articles)ISSN (Print) 1993-5048 - ISSN (Online) 1671-9433 Published by Springer-Verlag  [2468 journals]
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- Analysis of the Behavior of a Chemical Tanker in Extreme Waves
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Abstract: Abstract The behavior of a chemical tanker (CT) in extreme waves was discussed in detail, that is, in terms of rigid body heave and pitch motions, vertical bending moments (VBMs) amidships, green water, and slamming impacts through the analysis of the experimental data from model tests. Regular wave tests conducted for two wave steepness showed that the increase in wave steepness caused the increase in the asymmetry between hogging and sagging moments and the contribution of green water on deck to the decrease in vertical wave bending moments. Random uncertainty analysis of statistical values in irregular wave tests with various seeds revealed slight experimental uncertainties on motions and VBMs and slightly higher errors in slamming pressure peaks. With the increase in forward speed, experimental uncertainty on slamming pressures at the bow increased. Breather solutions of the nonlinear Schrödinger equation applied to generate tailored extreme waves of certain critical wavelengths showed a good performance in terms of ship response, and it was further verified for the CT.
PubDate: 2024-08-02
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- Impact of Various Coupled Motions on the Aerodynamic Performance of a
Floating Offshore Wind Turbine Within the Wind–Rain Field-
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Abstract: Abstract This study employed a computational fluid dynamics model with an overset mesh technique to investigate the thrust and power of a floating offshore wind turbine (FOWT) under platform floating motion in the wind–rain field. The impact of rainfall on aerodynamic performance was initially examined using a stationary turbine model in both wind and wind–rain conditions. Subsequently, the study compared the FOWT’s performance under various single degree-of-freedom (DOF) motions, including surge, pitch, heave, and yaw. Finally, the combined effects of wind–rain fields and platform motions involving two DOFs on the FOWT’s aerodynamics were analyzed and compared. The results demonstrate that rain negatively impacts the aerodynamic performance of both the stationary turbines and FOWTs. Pitch-dominated motions, whether involving single or multiple DOFs, caused significant fluctuations in the FOWT aerodynamics. The combination of surge and pitch motions created the most challenging operational environment for the FOWT in all tested scenarios. These findings highlighted the need for stronger construction materials and greater ultimate bearing capacity for FOWTs, as well as the importance of optimizing designs to mitigate excessive pitch and surge.
PubDate: 2024-07-24
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- Improved Inverse First-Order Reliability Method for Analyzing Long-Term
Response Extremes of Floating Structures-
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Abstract: Abstract Long-term responses of floating structures pose a great concern in their design phase. Existing approaches for addressing long-term extreme responses are extremely cumbersome for adoption. This work aims to develop an approach for the long-term extreme-response analysis of floating structures. A modified gradient-based retrieval algorithm in conjunction with the inverse first-order reliability method (IFORM) is proposed to enable the use of convolution models in long-term extreme analysis of structures with an analytical formula of response amplitude operator (RAO). The proposed algorithm ensures convergence stability and iteration accuracy and exhibits a higher computational efficiency than the traditional backtracking method. However, when the RAO of general offshore structures cannot be analytically expressed, the convolutional integration method fails to function properly. A numerical discretization approach is further proposed for offshore structures in the case when the analytical expression of the RAO is not feasible. Through iterative discretization of environmental contours (ECs) and RAOs, a detailed procedure is proposed to calculate the long-term response extremes of offshore structures. The validity and accuracy of the proposed approach are tested using a floating offshore wind turbine as a numerical example. The long-term extreme heave responses of various return periods are calculated via the IFORM in conjunction with a numerical discretization approach. The environmental data corresponding to N-year structural responses are located inside the ECs, which indicates that the selection of design points directly along the ECs yields conservative design results.
PubDate: 2024-07-23
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- Supercavitating Projectile Tail-Slaps Based on a Normal Distribution
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Abstract: Abstract The present study focuses on simulating supercavitating projectile tail-slaps with an analytical method. A model of 3σ-normal distribution tail-slaps for a supercavitating projectile is established. Meanwhile, the σ − κ equation is derived, which is included in this model. Next, the supercavitating projectile tail-slaps are simulated by combining the proposed model and the Logvinovich supercavity section expansion equation. The results show that the number of tail-slaps depends on where the initial several tail-slaps are under the same initial condition. If the distances between the initial several tail-slap positions are large, the number of tail-slaps will considerably decrease, and vice versa. Furthermore, a series of simulations is employed to analyze the influence of the initial angular velocity and the centroid. Analysis of variance is used to evaluate simulation results. The evaluation results suggest that the projectile’s initial angular velocity and centroid have a major impact on the tail-slap number. The larger the value of initial angular velocity, the higher the probability of an increase in tail-slap number. Additionally, the closer the centroid is to the projectile head, the less likely a tail-slap number increase. This study offers important insights into supercavitating projectile tail-slap research.
PubDate: 2024-07-17
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- Application of Feature, Event, and Process Methods to Leakage Scenario
Development for Offshore CO2 Geological Storage-
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Abstract: Abstract Offshore carbon dioxide (CO2) geological storage (OCGS) represents a significant strategy for addressing climate change by curtailing greenhouse gas emissions. Nonetheless, the risk of CO2 leakage poses a substantial concern associated with this technology. This study introduces an innovative approach for establishing OCGS leakage scenarios, involving four pivotal stages, namely, interactive matrix establishment, risk matrix evaluation, cause–effect analysis, and scenario development, which has been implemented in the Pearl River Estuary Basin in China. The initial phase encompassed the establishment of an interaction matrix for OCGS systems based on features, events, and processes. Subsequent risk matrix evaluation and cause-effect analysis identified key system components, specifically CO2 injection and faults/features. Building upon this analysis, two leakage risk scenarios were successfully developed, accompanied by the corresponding mitigation measures. In addition, this study introduces the application of scenario development to risk assessment, including scenario numerical simulation and quantitative assessment. Overall, this research positively contributes to the sustainable development and safe operation of OCGS projects and holds potential for further refinement and broader application to diverse geographical environments and project requirements. This comprehensive study provides valuable insights into the establishment of OCGS leakage scenarios and demonstrates their practical application to risk assessment, laying the foundation for promoting the sustainable development and safe operation of ocean CO2 geological storage projects while proposing possibilities for future improvements and broader applications to different contexts.
PubDate: 2024-07-17
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- Dynamic Analysis of the De-Ballasting Operations of a Floating Dock with a
Malfunctioning Pump-
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Abstract: Abstract During normal de-ballasting operations for floating docks, each ballast pump independently manages a specific group of ballast tanks. However, when a pump malfunctions, a connection valve between the two groups of ballast water systems is opened. This allows the adjacent pump to serve as a helper pump, simultaneously controlling two groups of ballast water systems. This study explores a full-scale floating dock’s dynamic behaviours during the de-ballasting operations under this situation through a numerical model. In the developed numerical model, the dock is described as a six-degree-of-freedom rigid body which is subjected to hydrostatic, hydrodynamic, and mooring loads. A hydraulic model of the piping network of the malfunctioning pump and the helper pump is proposed. A modified P-controller regulates opening angles of all tank valves for minimal pitch and roll. Two configurations of the floating dock, i. e., a single floating dock and a floating dock with an onboard vessel, are considered. The numerical results show that the optimal helper pumps can be identified regarding the pumps’ total de-ballasting capacity and the dock’s stability. The most severe scenarios can be determined in term of the dock’s maximum draught differences caused by its roll and pitch. The observed maximum draught differences remain small relative to the dock’s width, indicating the effectiveness of employing helper pumps and the proposed automatic ballast control strategy for one-pump malfunction scenarios.
PubDate: 2024-07-16
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- Experimental Investigation on Condensate Revaporization During Gas
Injection Development in Fractured Gas Condensate Reservoirs-
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Abstract: Abstract The gas field in the Bohai Bay Basin is a fractured metamorphic buried-hill reservoir with dual-media characteristics. The retrograde vaporization mechanism observed in this type of gas condensate reservoir differs significantly from that observed in sand gas condensate reservoirs. However, studies on improving the recovery of fractured gas condensate reservoirs are limited; thus, the impact of retrograde vaporization on condensate within fractured metamorphic buried-hill reservoirs remains unclear. To address this gap, a series of gas injection experiments are conducted in pressure-volume-temperature (PVT) cells and long-cores to investigate the retrograde vaporization effect of condensate using different gas injection media in fractured gas condensate reservoirs. We analyze the variation in condensate volume, gas-to-oil ratio, and condensate recovery during gas injection and examine the influence of various gas injection media (CO2, N2, and dry gas) under different reservoir properties and varying gas injection times. The results demonstrate that the exchange of components between injected gas and condensate significantly influences condensate retrograde vaporization in the formation. Compared with dry gas injection and N2 injection, CO2 injection exhibits a superior retrograde vaporization effect. At a CO2 injection volume of 1 PV, the percentage shrinkage volume of condensate is 13.82%. Additionally, at the maximum retrograde condensation pressure, CO2 injection can increase the recovery of condensate by 22.4%. However, the condensate recovery is notably lower in fractured gas condensate reservoirs than in homogeneous reservoirs, owing to the creation of dominant gas channeling by fractures, which leads to decreased condensate recovery. Regarding gas injection timing, the effect of gas injection at reservoir pressure on improving condensate recovery is superior to that of gas injection at the maximum retrograde condensation pressure. This research provides valuable guidance for designing gas injection development plans and dynamic tracking adjustments for fractured gas condensate reservoirs.
PubDate: 2024-07-16
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- Evaluation of Chamfered Tank with Porous Walls Against Sloshing
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Abstract: Abstract The sloshing in a tank with a specific geometric shape containing fluid was modeled numerically to reduce its effects by applying a porous medium to the tank wall. The thickness and position of the porous layer and the geometric shape of the tank were investigated as the main parameters to select an optimal approach to reduce the effects of sloshing. Different fluid tank filling percentages (Hw/Htot) were evaluated. Results indicate that performance at Hw/Htot = 0.33 and two tank modes with and without a porous environment layer have the greatest impact on reducing sloshing. A thickness of 30 cm and placement on the side walls are determined to be the ideal thickness and location of the porous layer. A porous layer with a thickness (t) relative to the tank length at the middle (Lm), t/Lm= 0.1 applied to the side walls of the tank effectively reduces the pressure by 65%. This study provided suggestions for the aspect ratio of a chamfered tank designed against sloshing.
PubDate: 2024-07-16
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- Ship Propeller Rotation Threshold to Prevent Erosion and Sedimentation in
Coastal Waters-
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Abstract: Abstract The rotation of a ship’s propeller can accelerate the water flow around it, which puts pressure on seabed particles. Continuous pressure on the seabed can significantly trigger erosion and sedimentation of coastal waters. Considering the impact that can be caused, the ship’s propeller rotation limit needs to be determined to avoid damage to the aquatic ecosystem. This research determines the threshold of ship propeller rotation based on the water flow velocity characteristic. Research has been carried out at the Hydrodynamics Laboratory on several variations of propeller rotation Rrmp (r/min) and water depth using empirical approaches, numerical simulations, and scale model experiments. Analysis based on general standard criteria for erosion and sedimentation shows that a propeller with a diameter (Dp) of 1.5 m is safe for propeller rotation at 25 r/min at all water depths. Then, the propeller rotation of 75 r/min is safe for a distance between the propeller axis and the bottom of the water equal to Dp. Meanwhile, rotation at 120 r/min is safe at a minimum distance of 1.5 Dp, and 230 r/min is safe for a minimum distance of 2.0 Dp. The propeller rotation threshold criteria are essential to determining the new under-keel clearance for environmentally friendly ship operations. Threshold values vary based on seabed particle type and water depth.
PubDate: 2024-07-09
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- Experimental Investigation of a Body Water Entry with a Water Jet
Cavitator-
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Abstract: Abstract This paper reports an experimental investigation on the flow of a water entry cavity formed with a water jet cavitator. To investigate the formation characteristics, systematic water entry experiments were conducted in a water tank under different water jet rates, entry velocities, entry angles, and nozzle diameters. The formation mechanism of the water entry cavity was also analyzed. Results indicate that before the model impacts the water surface for water entry with a water jet cavitator, a gas bubble is created, and its width increases as the model approaches the water surface. Moreover, the length of the water jet gradually reduces to zero due to the increase in the static pressure of the water. The formation of the cavity is directly correlated with the location of the stagnation point moving downstream from the far field of the water jet to the exit of the water jet nozzle with the increasing entry depth. The dominant parameter is the momentum ratio of the water jet and quiescent water.
PubDate: 2024-07-09
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- Integrated Optimization Scheduling Model for Ship Outfitting Production
with Endogenous Uncertainties-
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Abstract: Abstract Ship outfitting is a key process in shipbuilding. Efficient and high-quality ship outfitting is a top priority for modern shipyards. These activities are conducted at different stations of shipyards. The outfitting plan is one of the crucial issues in shipbuilding. In this paper, production scheduling and material ordering with endogenous uncertainty of the outfitting process are investigated. The uncertain factors in outfitting equipment production are usually decision-related, which leads to difficulties in addressing uncertainties in the outfitting production workshops before production is conducted according to plan. This uncertainty is regarded as endogenous uncertainty and can be treated as non-anticipativity constraints in the model. To address this problem, a stochastic two-stage programming model with endogenous uncertainty is established to optimize the outfitting job scheduling and raw material ordering process. A practical case of the shipyard of China Merchants Heavy Industry Co., Ltd. is used to evaluate the performance of the proposed method. Satisfactory results are achieved at the lowest expected total cost as the complete kit rate of outfitting equipment is improved and emergency replenishment is reduced.
PubDate: 2024-07-08
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- Simulation Study on the Migration Range of CO2 in the Offshore Saline
Aquifer-
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Abstract: Abstract The geological storage of carbon dioxide (CO2) is a crucial technology for mitigating climate change. Offshore deep saline aquifers have elicited increased attention due to their remarkable potential for storing CO2. During long-term storage, CO2 migration in a deep saline aquifer needs special attention to prevent it from reaching risk points and leading to security issues. In this paper, a mechanism model is established according to the geological characteristics of saline aquifers in an offshore sedimentary basin in China. The CO2 migration over 100 years is simulated considering geological changes such as permeability, dip angle, thickness, and salinity. The effects of injection conditions on the CO2 migration range are also investigated. Results reveal that the migration range of CO2 in the injection period exceeds 70%, even if the post-injection period’s duration is five times longer than that of the injection period. As the values of the above geological parameters increase, the migration range of CO2 increases, and permeability has a particularly substantial influence. Moreover, the influences of injection rate and well type are considerable. At high injection rates, CO2 has a greater likelihood of displacing brine in a piston-like scheme. CO2 injected by long horizontal wells migrates farther compared with that injected by vertical wells. In general, the plane migration range is within 3 000 m, although variations in the reservoir and injection parameters of the studied offshore saline aquifers are considered. This paper can offer references for the site selection and injection well deployment of CO2 saline aquifer storage. According to the studied offshore aquifers, a distance of at least 3 000 m from potential leakage points, such as spill points, active faults, and old abandoned wells, must be maintained.
PubDate: 2024-07-08
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- Monitoring Technologies for Marine Carbon Sequestration in Zhanjiang
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Abstract: Abstract Marine carbon sequestration is an important component of carbon dioxide capture, utilization and storage (CCUS) technology. It is crucial for achieving carbon peaking and carbon neutralization in China. However, CO2 leakage may lead to seabed geological disasters and threaten the safety of marine engineering. Therefore, it is of great significance to study the safety monitoring technology of marine carbon sequestration. Zhanjiang is industrially developed and rich in carbon sources. Owing to the good physical properties and reservoirs and trap characteristics, Zhanjiang has huge storage potential. This paper explores the disaster mechanism associated with CO2 leakage in marine carbon sequestration areas. Based on the analysis of the development of Zhanjiang industry and relevant domestic monitoring technologies, several suggestions for safety monitoring of marine carbon sequestration are proposed: application of offshore aquaculture platforms, expansion and application of ocean observation networks, carbon sequestration safety monitoring and sensing system. Intended to build a comprehensive and multi-level safety monitoring system for marine carbon sequestration, the outcome of this study provides assistance for the development of marine carbon sequestration in China’s offshore areas.
PubDate: 2024-07-08
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- Numerical Simulation and Experimental Study of the Rotor–Stator
Interaction of a Turbine Under Variable Flow Coefficients-
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Abstract: Abstract Clarifying the gas ingestion mechanism in the turbine disc cavity of marine gas turbines is crucial for ensuring the normal operation of turbines. However, the ingestion is influenced by factors such as the rotational pumping effect, mainstream pressure asymmetry, rotor–stator interaction, and unsteady flow structures, complicating the flow. To investigate the impact of rotor–stator interaction on ingestion, this paper decouples the model to include only the mainstream. This research employs experiments and numerical simulations to examine the effects of varying the flow coefficient through changes in rotational speed and mainstream flow rate. The main objective is to understand the influence of different rotor–stator interactions on the mainstream pressure field, accompanied by mechanistic explanations. The findings reveal inconsistent effects of the two methods for changing the flow coefficient on the mainstream pressure field. Particularly, the pressure distribution on the vane side primarily depends on the mainstream flow rate, while the pressure on the blade side is influenced by the mainstream flow rate and the attack angle represented by the flow coefficient. A larger angle of attack angle can increase pressure on the blade side, even surpassing the pressure on the vane side. Assessing the degree of mainstream pressure unevenness solely based on the pressure difference on the vane side is insufficient. This research provides a basis for subsequent studies on the influence of coupled real turbine rotor–stator interaction on gas ingestion.
PubDate: 2024-07-08
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- Energy-Efficient and Reliable Deployment Models for Hybrid Underwater
Acoustic Sensor Networks with a Mobile Gateway-
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Abstract: Abstract This work proposes an innovative approach to evaluate the functional characteristics of a heterogeneous underwater wireless acoustic sensor network (UWASN) using a stochastic model and the network connectivity criterion. The connectivity criterion is probabilistic and considers inherently distinct groups of parameters: technical parameters that determine the network function at specific levels of the communication stack and physical parameters that describe the environment in the water area. The proposed approach enables researchers to evaluate the network characteristics in terms of energy efficiency and reliability while considering specific network and environmental parameters. Moreover, this approach is a simple and convenient tool for analyzing the effectiveness of protocols in various open systems interconnection model levels. It is possible to assess the potential capabilities of any protocol and include it in the proposed model. This work presents the results of modeling the critical characteristics of heterogeneous three-dimensional UWASNs of different scales consisting of stationary sensors and a wave glider as a mobile gateway, using specific protocols as examples. Several alternative routes for the wave glider are considered to optimize the network’s functional capabilities. Optimal trajectories of the wave glider’s movement have been determined in terms of ensuring the efficiency and reliability of the hybrid UWASN at various scales. In the context of the problem, an evaluation of different reference node placement was to ensure message transmission to a mobile gateway. The best location of reference nodes has been found.
PubDate: 2024-07-08
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- A Succinct Review on the Numerical and Experimental Performance Evaluation
Techniques for Composite Marine Propellers-
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Abstract: Abstract Understanding the behaviour of composite marine propellers during operating conditions is a need of the present era since they emerge as a potential replacement for conventional propeller materials such as metals or alloys. They offer several benefits, such as high specific strength, low corrosion, delayed cavitation, improved dynamic stability, reduced noise levels, and overall energy efficiency. In addition, composite materials undergo passive deformation, termed as “bend-twist effect”, under hydrodynamic loads due to their inherent flexibility and anisotropy. Although performance analysis methods were developed in the past for marine propellers, there is a significant lack of literature on composite propellers. This article discusses the recent advancements in experimental and numerical modelling, state-of-the-art computational technologies, and mutated mathematical models that aid in designing, analysing, and optimising composite marine propellers. In the initial sections, performance evaluation methods and challenges with the existing propeller materials are discussed. Thereafter, the benefits of composite propellers are critically reviewed. Numerical and experimental FSI coupling methods, cavitation performance, the effect of stacking sequence, and acoustic measurements are some critical areas discussed in detail. A two-way FSI-coupled simulation was conducted in a non-cavitating regime for four advanced ratios and compared with the literature results. Finally, the scope for future improvements and conclusions are mentioned.
PubDate: 2024-07-06
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- The AVO Effect of Formation Pressure on Time-Lapse Seismic Monitoring in
Marine Carbon Dioxide Storage-
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Abstract: Abstract The phase change of CO2 has a significant bearing on the siting, injection, and monitoring of storage. The phase state of CO2 is closely related to pressure. In the process of seismic exploration, the information of formation pressure can be response in the seismic data. Therefore, it is possible to monitor the formation pressure using time-lapse seismic method. Apart from formation pressure, the information of porosity and CO2 saturation can be reflected in the seismic data. Here, based on the actual situation of the work area, a rockphysical model is proposed to address the feasibility of time-lapse seismic monitoring during CO2 storage in the anisotropic formation. The model takes into account the formation pressure, variety minerals composition, fracture, fluid inhomogeneous distribution, and anisotropy caused by horizontal layering of rock layers (or oriented alignment of minerals). From the proposed rockphysical model and the well-logging, cores and geological data at the target layer, the variation of P-wave and S-wave velocity with formation pressure after CO2 injection is calculated. And so are the effects of porosity and CO2 saturation. Finally, from anisotropic exact reflection coefficient equation, the reflection coefficients under different formation pressures are calculated. It is proved that the reflection coefficient varies with pressure. Compared with CO2 saturation, the pressure has a greater effect on the reflection coefficient. Through the convolution model, the seismic record is calculated. The seismic record shows the difference with different formation pressure. At present, in the marine CO2 sequestration monitoring domain, there is no study involving the effect of formation pressure changes on seismic records in seafloor anisotropic formation. This study can provide a basis for the inversion of reservoir parameters in anisotropic seafloor CO2 reservoirs.
PubDate: 2024-07-06
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- Effects of Split Injection on Combustion, Emissions, and Intermediate
Species of Natural Gas High-Pressure Direct Injection Engine-
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Abstract: Abstract Using natural gas (NG) as the primary fuel helps alleviate the fossil fuel crisis while reducing engine soot and nitrogen oxide (NOX) emissions. In this paper, the influences of a novel split injection concept on an NG high pressure direct injection (HPDI) engine are examined. Four typical split injection strategies, namely split pre-injection of pilot diesel (PD) and NG, split post-injection of PD and NG, split pre-injection of NG, and split post-injection of PD, were developed to investigate the influences on combustion and emissions. Results revealed that split pre-injection of NG enhanced the atomization of PD, whereas the split post-injection of NG lowered the temperature in the core region of the PD spray, resulting in the deterioration of combustion. The effect of the split injection strategy on indicated thermal efficiency exceeded 7.5%. Split pre-injection was favorable to enhancing thermal efficiency, whereas split post-injection was not. Ignition delay, combustion duration, and premixed combustion time proportion were affected by injection strategies by 3.8%, 50%, and 19.7%, respectively. Split pre-injection increased CH4 emission in the exhaust. Split post-injection, especially split post-injection of PD and NG, reduced the unburned CH4 emission by approximately 30%. When the split post-injection ratio was less than 30%, the trade-off between NOX and soot was interrupted. The distribution range of hydroxyl radicals was expanded by pre-injection, and NOX was generated in the region where the NG jet hit the wall. This paper provides valuable insights into the optimization of HPDI injection parameters.
PubDate: 2024-07-05
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- Design and Analysis of Offshore Wind Turbines: Problem Formulation and
Optimization Techniques-
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Abstract: Abstract Researchers often explore metaheuristic algorithms for their studies. These algorithms possess unique features for solving optimization problems and are usually developed on the basis of real-world natural phenomena or animal and insect behavior. Numerous fields have benefited from metaheuristic algorithms for solving real-world optimization problems. As a renewable energy source, offshore wind energy is a rapidly developing subject of research, attracting considerable interest worldwide. However, designing offshore wind turbine systems can be challenging because of the large space of design parameters and different environmental conditions, and the optimization of offshore wind turbines can be extremely expensive. Nevertheless, advanced optimization methods can help to overcome these challenges. This study explores the use of metaheuristic algorithms in optimizing the design of wind turbines, including wind farm layout and wind turbine blades. Given that offshore wind energy relies more heavily on subsidies than fossil fuel-based energy sources, lowering the costs for future projects, particularly by developing new technologies and optimizing existing methods, is crucial.
PubDate: 2024-07-05
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- Verification and Validation for Large Eddy Simulation of Cavitating Flow
Around a Projectile Near the Free Surface-
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Abstract: Abstract Verification and validation (V&V) is a helpful tool for evaluating simulation errors, but its application in unsteady cavitating flow remains a challenging issue due to the difficulty in meeting the requirement of an asymptotic range. Hence, a new V&V approach for large eddy simulation (LES) is proposed. This approach offers a viable solution for the error estimation of simulation data that are unable to satisfy the asymptotic range. The simulation errors of cavitating flow around a projectile near the free surface are assessed using the new V&V method. The evident error values are primarily dispersed around the cavity region and free surface. The increasingly intense cavitating flow increases the error magnitudes. In addition, the modeling error magnitudes of the Dynamic Smagorinsky–Lilly model are substantially smaller than that of the Smagorinsky–Lilly model. The present V&V method can capture the decrease in the modeling errors due to model enhancements, further exhibiting its applicability in cavitating flow simulations. Moreover, the monitoring points where the simulation data are beyond the asymptotic range are primarily dispersed near the cavity region, and the number of such points grows as the cavitating flow intensifies. The simulation outcomes also suggest that the re-entrant jet and shedding cavity collapse are the chief sources of vorticity motions, which remarkably affect the simulation accuracy. The results of this study provide a valuable reference for V&V research.
PubDate: 2024-07-01
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