Journal of Marine Science and Technology, Journal Year: 2024, Volume and Issue: unknown
Published: Dec. 21, 2024
Language: Английский
Ocean Engineering, Journal Year: 2023, Volume and Issue: 283, P. 115175 - 115175
Published: June 21, 2023
Language: Английский
Citations
9
Journal of Marine Science and Engineering, Journal Year: 2024, Volume and Issue: 12(4), P. 608 - 608
Published: March 31, 2024
This study verifies the effects of deployment parameters on safe separation Autonomous Underwater Vehicles (AUVs) and mission payloads. The initial phase is meticulously modeled based computational fluid dynamics (CFD) simulations employing cubic constitutive Shear Stress Transport (SST) k-ω turbulence model overset grid technologies. characterized by a 6-degree-of-freedom (6-DOF) framework incorporating Dynamic Fluid-Body Interaction (DFBI), supported empirical validation. SST demonstrates superior performance in managing flows adverse pressure gradients separation. DFBI entails computationally modeling fluid–solid interactions during motion or deformation. utilization grids presents several advantages, including enhanced efficiency concentrating resources solely regions interest, simplified handling intricate geometries moving bodies, adaptability adjusting to accommodate changing simulation conditions. research analyzes payloads’ trajectories attitude adjustments after release from AUVs under various cruising speeds dynamics, such as descent angular velocities. Additionally, this evaluates varying ocean currents at different depths safety. Results indicate that interaction between payloads increases higher navigational speeds, reducing speed degrading stability. As drop velocities increase, fast transition through AUV’s immediate flow field promotes core process pitch angle management upon deployment. Optimizing pitching velocity prolongs time for reach their maximum angle, thus decreasing horizontal displacement improving Deploying greater alleviates influence currents, thereby disturbances payload
Language: Английский
Citations
3
Physics of Fluids, Journal Year: 2023, Volume and Issue: 35(8)
Published: Aug. 1, 2023
A numerical approach is established to study the hydrodynamic performance using an amphibious transport vehicle (ATV) as a research object. Numerical calculation based on Reynolds average Navier–Stokes method studied in terms of first layer grid height, surface meshing partition scale, and prismatic coefficient. Through uncertainty analysis, correctness convergence are verified. Towing tests conducted compare experimental data with simulation results, which validated reliability under all working conditions. Results show that will affect simulated error 3.91% for resistance 4.21% trim, meeting requirements analysis accuracy. Based proposed approach, optimization design carried out improve ATV. Effects bow plate angle, stern flap install height studied. Latin hypercube used sampling design, Kriging applied establish approximate model. The cross-validation leave-one-out method. Particle swarm parameter optimization, optimized configuration verified approach. indicate combination shows excellent improvement vehicles. model only 0.292%, fully verifies its accuracy effectiveness. ATV best drag reduction 38.81% compared original
Language: Английский
Citations
6
Silniki Spalinowe/Combustion Engines, Journal Year: 2024, Volume and Issue: unknown
Published: March 2, 2024
The issue related to the motion resistance of a rail vehicle is very important for energy, environmental and energy consumption as well performance with dynamic points. latter aspect applies in particular traction vehicles. article presents several models movement freight train used by various railway authorities, Polish foreign rolling stock. values obtained from were verified against tested carrying aggregate. On basis records locomotive recorder, linear speed changes over time coasting paths (without drive) determined. train, stop determined on UIC 544-1 card, which analyzed train.
Language: Английский
Citations
2
Journal of Marine Science and Engineering, Journal Year: 2024, Volume and Issue: 12(4), P. 570 - 570
Published: March 27, 2024
This study aims to investigate the influence of wheel configurations on hydrodynamic resistance an amphibious vessel through experiments and simulations. To evaluate performance associated with attachments, three were examined: without caterpillars, both caterpillars shoe−paddles. A comprehensive series computational fluid dynamics (CFD) simulations conducted for these attachment types, complemented by experimental validations. The Volume-of-Fluid (VOF) model was employed in CFD capture free surface movement, Dynamic Fluid–Body Interaction (DFBI) adopted represent two-degree-of-freedom motion vessel, specifically trim sinkage. total derived from calculated across a range Froude numbers (Fns), including design speed target validated tests wave basin equipped towing facility. analysis indicated general increase when attachments added vessel. Remarkably, at (Fn = 0.27), shoe−paddles exceeded that configuration any more than 75.7%. These results provide crucial insights preliminary stage vessels, particularly those intended marine debris collection hard-to-reach areas.
Language: Английский
Citations
1
Ocean Engineering, Journal Year: 2023, Volume and Issue: 293, P. 116592 - 116592
Published: Dec. 27, 2023
Language: Английский
Citations
2
Ships and Offshore Structures, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 14
Published: Feb. 15, 2024
Resistance characteristics of amphibious vehicles are crucial for their sailing speed and battlefield survivability. This study proposes the installation hydrofoils at wheel cavity to reduce resistance enhance performance. Two hydrofoil designs four shapes analyzed determine optimal drag reduction design. Towing tests numerical simulations employed investigate evaluate hydrodynamic performance vehicles. The impact on is analysed elucidated through a comprehensive analysis surface pressure distribution, attitude, energy consumption in flow field. Results demonstrate that, except elongation-hydrofoil, other three all show significant optimisation medium high speeds Fr>0.5, with improved effectiveness as increases. Among shapes, curve-hydrofoil exhibits best overall effect (18%) peak compression ability (6.68%), owing its ample lift force trim capability.
Language: Английский
Citations
0
Inventions, Journal Year: 2024, Volume and Issue: 9(3), P. 48 - 48
Published: April 26, 2024
The use of tag devices in marine environments has become indispensable attaining a better understanding life and contributing to conservation efforts. However, the successful deployment operation underwater tags both depend significantly on their hydrodynamic characteristics, particularly resistance motion stability various environmental conditions. Herein, comprehensive study characteristics optimization an designed for monitoring blue sharks is presented. Firstly, validation process conducted by comparing computational fluid dynamics (CFD) results with experimental data from Myring’s study, focusing tag’s body impact operational Subsequently, validated CFD model applied assess performance under different flow conditions, velocities, angles attack. Through iterative simulations, including mesh independence studies boundary condition adjustments, identifies key parameters influencing stability. Furthermore, paper proposes implements design modifications, incorporation stabilizing fins, aimed at minimizing improving equilibrium position. effectiveness these enhancements demonstrated through comparative analysis pitching moments preliminary optimized configurations. Overall, provides valuable insights into behavior offers practical recommendations optimizing minimize interference movement tagged animals.
Language: Английский
Citations
0
Heliyon, Journal Year: 2024, Volume and Issue: 10(15), P. e35085 - e35085
Published: July 23, 2024
The series-parallel hybrid system has attracted much attention from scholars for its effective integration of the power advantages and operating characteristics different sources, which is influenced by international emission regulations, energy-saving reduction policies. As such, a powertrain introduced to amphibious vehicle, an innovative topology architecture proposed. Meanwhile, operation mode energy efficiency are investigated during working process. Firstly, flow simulation model gas-electric propulsion constructed using modular modeling approach. Secondly, four modes, namely mechanical propulsion, electric charging mode, were formulated due fact that multiple forms sources in form natural gas engine reversible motor. states under modes. comprehensive investigation associated with storage start-up was conducted each specific mode. results research indicated can reach up 35.15 %, gain wide range motor's high efficiency. obtain highest 35.88 fully demonstrates coordinating complementing two This also provides theoretical empirical support optimizing matching formulating management strategies.
Language: Английский
Citations
0
Journal of Marine Science and Technology, Journal Year: 2024, Volume and Issue: unknown
Published: Dec. 21, 2024
Language: Английский
Citations
0