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Статті в журналах з теми "Underwater spatial dynamics"
1
Grumondz, V. T., R. V. Pilgunov, M. V. Vinogradov, and N. V. Maykova. "Lateral Motion of Towed Underwater Vehicle within the Problem of Continental Shelf Monitoring." Herald of the Bauman Moscow State Technical University. Series Mechanical Engineering, no. 1 (130) (February 2020): 56–69. http://dx.doi.org/10.18698/0236-3941-2020-1-56-69.
Повний текст джерелаАнотація:
Lateral motion dynamics was studied of a robotic towed underwater system designed to monitor the continental shelf and consisting of a towed vehicle and a tow wireline. In regard to underwater vehicles of the type in question, it is quite correct to represent spatial motion in the form of a super-position consisting of two flat motions, i.e., longitudinal motion in the vertical plane and lateral motion in the horizontal plane. Dynamics of the towed system longitudinal motion within the monitoring problem was considered in a previously published work by the authors. The present work is its natural continuation and development traditionally accepted in the problems of the underwater vehicles spatial motion mechanics. Diagram of the towed vehicle operation and its hydrodynamic characteristics are presented; besides, mathematical model of a wireline and also a model of the wireline-towed vehicle system lateral motion were constructed. Probable steady system motions were analyzed, issues of balancing, as well as those of the towed vehicle dynamic stability when moving at a constant depth were considered. Results of numerical calculations were provided. The results obtained were considered in conjunction with the results of the authors' above mentioned work related to the towed vehicle longitudinal motion and make it possible to select such system parameters that provide the specified character of spatial movements in the process of monitoring the continental shelf taking into consideration the need to perform turns in the horizontal plane at changing directions and to ensure vertical maneuvers when avoiding underwater obstacles.
2
Kinsey, James C., Maurice A. Tivey, and Dana R. Yoerger. "Dynamics and navigation of autonomous underwater vehicles for submarine gravity surveying." GEOPHYSICS 78, no. 3 (May 1, 2013): G55—G68. http://dx.doi.org/10.1190/geo2012-0181.1.
Повний текст джерелаАнотація:
We investigated the effect of autonomous underwater vehicle (AUV) dynamics and navigation on underway submarine gravimetry. Our research was motivated by the need to obtain spatially dense marine gravity measurements close to the source of subkilometer-scale geologic features in the shallow oceanic crust. Such measurements have been previously obtained, for instance, with piloted submarines and towed sleds; however, the high cost and, in the case of on-bottom measurements, poor spatial sampling preclude routine acquisition of these measurements. Continuous underway gravity surveys with AUVs is a compelling cost-effective option, but this method requires separating the AUV accelerations from the measured gravity. We show that AUVs with a large distance between the center of buoyancy and the center of gravity have lower vertical accelerations than torpedo-shaped AUVs and consequentially are better suited for underway gravity surveys. Furthermore state estimators, which combine sensor measurements and models of the vehicle’s motion, provide superior estimates of the vehicle’s vertical accelerations than methods used in previous underway submarine gravity surveys. We simulated the use of these navigation methods in detecting dike swarms at the East Pacific Rise. Analysis showed that we can shorten filters used in reducing gravity data and consequentially provide improved measurements of the free-water anomaly with a minimal detectable spatial wavelength approximately 65% lower than previously reported results.
3
Olden, Julian D., Oliver Miler, and Alexander Bijaye. "Lake-wide mapping of littoral habitat using underwater videography." Knowledge & Management of Aquatic Ecosystems, no. 423 (2022): 18. http://dx.doi.org/10.1051/kmae/2022018.
Повний текст джерелаАнотація:
Littoral zones − referring to benthic areas above the light compensation depth − provide numerous ecosystem functions, including mediating light, temperature, and nutrient dynamics, and supporting important foraging and refuge areas for macroinvertebrates, fishes and water birds. Habitat assessments of littoral zones remain fundamental to lake and fisheries management, however traditional field surveys are time-intensive and limited in their spatial extent, whereas desktop evaluations using remote sensing and aerial imagery are cost prohibitive and require considerable data processing expertise. In light of these challenges, this study demonstrated the ability to use simple, cost-effective underwater videography to conduct lake-wide spatially-continuous assessments of littoral habitat. For lakes across a gradient of shoreline and riparian development in northwestern United States, we map the areal coverage of macrophytes, coarse woody habitat, bottom substrates, and artificial structures in littoral zones. Underwater videography represents a relevant tool for environmental monitoring because it allows for the estimation of littoral habitats at fine spatial grains across broad spatial extents. Data can also be obtained rapidly and at relatively low cost, providing a permanent record of habitat conditions that can used to monitor trends over time.
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Garus, Jerzy. "Control-Oriented Modelling of Spatial Motion of Autonomous Underwater Vehicle." Solid State Phenomena 196 (February 2013): 109–16. http://dx.doi.org/10.4028/www.scientific.net/ssp.196.109.
Повний текст джерелаАнотація:
Modelling of three-dimensional motion of an underwater vehicle along a time-varying reference trajectory with predefined speed profiles is presented in the paper. A nonlinear mathematical model with unknown nonlinearities describes the vehicle’s dynamics. Command signals are generated by an adaptive autopilot consisting of three independent controllers with a parameter adaptation law implemented. A control performance is guaranteed by suitably choosing design parameters. Selected results of computer simulations are inserted to demonstrate quality and effectiveness of the approach.
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Santhakumar, M. "Proportional-Derivative Observer-Based Backstepping Control for an Underwater Manipulator." Mathematical Problems in Engineering 2011 (2011): 1–18. http://dx.doi.org/10.1155/2011/397092.
Повний текст джерелаАнотація:
This paper investigates the performance of a new robust tracking control on the basis of proportional-derivative observer-based backstepping control applied on a three degrees of freedom underwater spatial manipulator. Hydrodynamic forces and moments such as added mass effects, damping effects, and restoring effects can be large and have a significant effect on the dynamic performance of the underwater manipulator. In this paper, a detailed closed-form dynamic model is derived using the recursive Newton-Euler algorithm, which extended to include the most significant hydrodynamic effects. In the dynamic modeling and simulation, the actuator and sensor dynamics of the system are also incorporated. The effectiveness of the proposed control scheme is demonstrated using numerical simulations along with comparative study between conventional proportional-integral-derivative (PID) controls. The results are confirmed that the actual states of joint trajectories of the underwater manipulator asymptotically follow the desired trajectories defined by the reference model even though the system is subjected to external disturbances and parameter uncertainties. Also, stability of the proposed (model reference control) control scheme is analyzed.
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Zhang, Junhao, Yinglong Chen, Yi Liu, and Yongjun Gong. "Dynamic Modeling of Underwater Snake Robot by Hybrid Rigid-Soft Actuation." Journal of Marine Science and Engineering 10, no. 12 (December 5, 2022): 1914. http://dx.doi.org/10.3390/jmse10121914.
Повний текст джерелаАнотація:
For decades, underwater vehicles have been performing underwater operations, which are critical to the development and upgrading of underwater robots. With the advancement of technology, various types of robots have been developed. The underwater robotic snake is a bioinspired addition to the family of underwater robotic vehicles. In this paper, we propose an innovative underwater snake robot actuated by rigid propulsions and soft joints, which can improve the swimming efficiency and flexibility of the robot and reduce the probability of collision leading to damage. Existing math models of robotic snakes typically incorporate only planar motion, rarely considering spatial motion. So, we formulate a complete three-dimensional dynamic model for the robotic snake, which is extended by deriving expressions for the geometric Jacobians. This modeling approach is well suited since it provides compact matrix expressions and easy implementation. We use the constant curvature method to describe the configuration of the soft joint, use the Lagrangian method to obtain its dynamic characteristics, and focus on deriving the visco-hyperelastic mechanical energy of the soft material. Next, the local dynamics of soft members are extended as a nonholonomic constraint form for modeling the snake robot. Finally, the multi-modal swimming behavior of the robot has been verified by simulations, including forward and backward rectilinear motion, yaw turning, pitch motion, and spiral rising motion. The overall results demonstrate the effectiveness and the versatility of the developed dynamic model in the prediction of the robot trajectory, position, orientation, and velocity.
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Benoit-Bird, Kelly J., and Whitlow W. L. Au. "Spatial dynamics of a nearshore, micronekton sound-scattering layer." ICES Journal of Marine Science 60, no. 4 (January 1, 2003): 899–913. http://dx.doi.org/10.1016/s1054-3139(03)00092-4.
Повний текст джерелаАнотація:
AbstractIn the Hawaiian Islands, there is a distinct resident community of micronekton, distributed along a narrow band where the upper underwater slopes of the islands meet the oceanic, mesopelagic environment. This mesopelagic boundary community serves as an important food resource to many animals. The goal of this work was to examine spatial heterogeneity of the Hawaiian mesopelagic boundary biomass at a range of scales, in the context of its diel vertical and horizontal migrations. A modified echosounder was used to sample the coasts of three Hawaiian Islands, permitting a range of scales from several meters to several kilometers to be assessed rapidly. The Hawaiian mesopelagic boundary community fits the hierarchical model of patch structure with patches within patches that are part of a larger-scale matrix of patches. Large differences in the overall distribution patterns of the mesopelagic boundary community exist along with a wide range of overall mesopelagic-animal densities. High animal-density locations have boundary-community layers with a large (kilometers) horizontal extent, and low animal-density locations have small (tens of meters), discrete patches. Higher animal-density locations are also more complex than low-density sites, with more levels of patchiness within the same range of spatial scales. Both time of day and distance from shore significantly affected the geometric and density characteristics as well as the distribution of aggregations within the boundary layer. Horizontal and vertical structures of the mesopelagic boundary community are also coupled. In high-density sites, there is strong vertical layering in acoustic-scattering strength while in low-density sites vertical acoustic structure is absent. The differences observed in the distribution of the mesopelagic boundary community at different levels of overall mesopelagic-animal density suggest biological forcing as the dominant mechanism. A description of heterogeneity in the mesopelagic boundary community in Hawaii is the first step in understanding its importance to both neritic and oceanic ecosystems and its potential for linking these two systems.
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Borsje, Bas, Maurits Kruijt, Jebbe Van der Werf, Suzanne Hulscher, and Peter Herman. "MODELING BIOGEOMORPHOLOGICAL INTERACTIONS IN UNDERWATER NOURISHMENTS." Coastal Engineering Proceedings 1, no. 32 (January 29, 2011): 104. http://dx.doi.org/10.9753/icce.v32.sediment.104.
Повний текст джерелаАнотація:
To prevent sandy coastlines from further erosion, nourishments are executed in which sand is usually put underwater at the foreshore. Waves and currents transport the sand on the beach and in this way stabilize the coastal profile. Little is known about the interactions of these so-called shoreface nourishments with the benthic populations inhabiting the coastal strip. Benthos is affected by the nourishments, but benthic populations could in turn affect the morphological evolution of the nourished coast. Monitoring has shown that the benthic community will mainly recovery after ca. 1 year. However, the impact of benthos on the sediment dynamics and hydrodynamics is unknown. In this paper we focus on tube building worms, which have a large abundance in the foreshore, live in patches of several square meters in diameter and protrude several centimeters from the sediment in the water column. Tube building worms are included in a numerical modeling tool (Delft3D), by explicitly accounting for the influence of cylindrical structures on drag and turbulence by an extra source term of friction force in the momentum equation and an extra source term of Total Kinetic Energy (TKE) and turbulent energy dissipation in the k-ε equations respectively. The model is validated against field and flume experiments and it shows a significant influence on flow velocities near the bed, bed shear stress and bed-load transport rates. Moreover, model results reveal that tube building worms are able to stabilize nourishments and slow down the migration of the outer breaker bar. Present model explorations indicate that future research should focus on the measurement of the patchy distribution of bio-engineers in the foreshore and their impact on the sediment dynamics and hydrodynamics. Such knowledge will enable process based modeling of the spatial and temporal variation in biological activity on the morphological development of the coastal profile and also it will lead to validation of the proposed model with field measurements.
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Lebid, Oleksii G. "Five-mode quasilinear model of nonlinear dynamics of extended system." Environmental safety and natural resources 38, no. 2 (June 30, 2021): 104–20. http://dx.doi.org/10.32347/2411-4049.2021.2.104-120.
Повний текст джерелаАнотація:
Distributed systems are widely used in practice. These are cosmic ligaments in the near-Earth space with a length of tens of kilometers. They approximate reinforced concrete piles in the soil when calculating the stress-strain state and assessing the technical condition; pipelines both in air and in liquid, underwater towed systems. Known underwater airlift systems of great length for the extraction of minerals (nodules) from the ocean floor with a length of 5-10 km. To solve the problems of the dynamics of such systems in various environments, the well-known mathematical models are not quite correct from the point of view of taking into account the variety of wave processes. It determines the need to build refined wave models. A new quasilinear mathematical model, which describes the nonlinear four-mode dynamics of the distributed system in the spatially inhomogeneous field of mass and surface forces, has been obtained. It is described by a nonlinear system of twelve first-order partial differential equations. For it, the principles of ultimate and hyperbolicity are fulfilled. Together with the boundary and initial conditions, it can be used to describe dynamics and statics of geometrically and physically nonlinear rod elements, piles in the ground, crane equipment ropes, mine lifts, aerial cableways, towed systems in liquid and gas flow, etc. For two-mode spatial reduction of the model, the theorem about correctness of Cauchy problem has been considered. As a result of the calculations, the earlier assumptions about the movement of the cable along its initial configuration were changed as the length of the cable changed. It has been found out that this assumption is only true for the initial transition participant. It is also established that at a given tachogram in the configuration of the towed line, there is a point of inflection, which shifts from top to bottom when lifting it. It can be a factor in the looping, contributing to the breakage of the cable system during towing.
10
Jiménez-Romero, Raúl, Luis Miguel Fernández-Salas, Desirée Palomino, Ricardo Félix Sánchez-Leal, and Yolanda Vila. "Discovering the Fine-Scale Morphology of the Gulf of Cádiz: An Underwater Imaging Analysis." Journal of Marine Science and Engineering 10, no. 5 (May 10, 2022): 651. http://dx.doi.org/10.3390/jmse10050651.
Повний текст джерелаАнотація:
The dense and deep water flow that leaves the Mediterranean Sea to the Atlantic flows through the upper and middle slope of the Gulf of Cádiz as a powerful bottom stream that models and interacts with bathymetry. The detailed analysis of underwater images, obtained with a photogrammetric sled in the central area of the upper and middle slope of the Gulf of Cádiz, together with multibeam bathymetry and oceanographic and sediment types data, has allowed conducting a detailed study of the seafloor microtopography and the predominant oceanographic dynamics in the study area. Different fine-scale spatial bedforms were identified, such as ripples, dunes, burrows, mounds, obstacle marks, rock bottoms, and low-roughness bottoms using underwater images. Besides, a geostatistical study of the different video transects studied was carried out and allowed us to differentiate three types of bottoms depending on the processes that affect their microtopography.
Дисертації з теми "Underwater spatial dynamics"
1
Allan, Michele Margaret. "‘LIQUID SPACE’: a visual investigation of the sea as an empirical, experiential and metaphoric space." Phd thesis, 2013. http://hdl.handle.net/1885/13491.
Повний текст джерелаАнотація:
Artworks produced in this studio-based research (option D) involve exploration
of the ‘liquid space’ of the sea, not just in its physical and sensual nature and the
way the sea looks, but also with what the sea inspires. They explore the spatial
dynamics of underwater terrains, convergences of inner and outer ‘space’, and
question if and how the numinous and immaterial might be made manifest in the
material. References to the traditional story of Jonah and the Whale operate as a
contemporary metaphor for the sea as a site of death and renewal. Through the
creation of series of paintings, works on paper and engraved glass overlays, the sea
is examined as a synthesis of the complex and diverse on many fluidly interacting
levels, including the empirical, experiential and metaphoric. As a poetic space with
many levels of resonance, it becomes ground for exploring the creative process,
the nature of being and processes of transformation and change within each.
Research questions include: What might a contemporary expression of
the interaction of the physical and metaphysical self be like? How might a
synthesis of abstraction and representation be created in the visual language of
painting? How might concepts of unity be reconciled with rhythms of death and
renewal, transformation and change? Does unity necessarily mean uniform?
A significant aspect of this research has been the generation of artworks on or through
field trips to locations by the sea - Cape Leveque in North-east Australia, Heron Island
Research Station on the Great Barrier Reef and South Bruny Island in Tasmania. In
exploring the interface between abstraction and representation, unity and diversity,
and the inner and outer worlds, I have discovered the sea rich ground for reenvisioning
these seeming opposites as co-creative, relational and finally inseparable.
The ‘Wave’ structure of the Exegesis is more than usually organic in form. Conventional
chapters are replaced by multiple and varied sections, each called a WAVE and written
in changing ‘voice’. Echoing the shifting rhythms of the sea, and in order to correspond
more directly to the way practice-driven research creates meaning, the wave structure
reflects the wider concerns of the research to synthesise the unexpected and diverse.
Частини книг з теми "Underwater spatial dynamics"
1
Garus, Jerzy. "Model Reference Adaptive Control of Underwater Robot in Spatial Motion." In Modelling Dynamics in Processes and Systems, 71–83. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-92203-2_5.
Повний текст джерелаТези доповідей конференцій з теми "Underwater spatial dynamics"
1
Xie, Qing, Tao Wang, and Shiqiang Zhu. "Dynamical Characteristics of a Hydraulic Soft Actuator With Three Degrees of Freedom." In ASME/BATH 2021 Symposium on Fluid Power and Motion Control. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/fpmc2021-68734.
Повний текст джерелаАнотація:
Abstract In recent years, increasing attention and expanding research have been devoted to the study and application of soft actuators. Inherent compliance equips soft actuators with such advantages as incomparable flexibility, good environmental adaptability, safe interaction with the environment, etc. However, the highly nonlinear also bring challenges to modeling of dynamics. This study aims to explore the dynamical characteristics of an underwater hydraulic soft actuator. The actuator has three fiber-reinforced elastomer chambers distributed symmetrically inside. By controlling the pressure in the chambers through a hydraulic power system, the actuator can achieve spatial motion with three degrees of freedom. To describe the relationship between the input pressure combination and the actuator movement, a dynamic model considering the nonlinearity of viscoelastic material is developed based on Lagrangian method and constant curvature hypothesis. A series of experiments are carried out, including single-chamber actuation and multi-chamber actuation. The test results verify the effectiveness and precision of the model. Finally, the effects of the geometrical features on dynamic response are investigated through model-based simulation, which can provide guidance to parameter optimization. The proposed dynamic model can also contribute to behavior analysis, performance prediction, and motion control of the hydraulic soft actuator.
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Patrikalakis, Nicholas M., Joshua Leighton, Georgios Papadopoulos, Gabriel Weymouth, Hanna Kurniawati, Pablo Valdivia y Alvarado, Tawfiq Taher, and Rubaina Khan. "Modeling and Inspection Applications of a Coastal Distributed Autonomous Sensor Network." In ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/omae2012-83812.
Повний текст джерелаАнотація:
Real time in-situ measurements are essential for monitoring and understanding physical and biochemical changes within ocean environments. Phenomena of interest usually display spatial and temporal dynamics that span different scales. As a result, a combination of different vehicles, sensors, and advanced control algorithms are required in oceanographic monitoring systems. In this study our group presents the design of a distributed heterogeneous autonomous sensor network that combines underwater, surface, and aerial robotic vehicles along with advanced sensor payloads, planning algorithms and learning principles to successfully operate across the scales and constraints found in coastal environments. Examples where the robotic sensor network is used to localize algal blooms and collect modeling data in the coastal regions of the island nation of Singapore and to construct 3D models of marine structures for inspection and harbor navigation are presented. The system was successfully tested in seawater environments around Singapore where the water current is around 1–2m/s.
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IVAVIČIŪTĖ, Giedrė. "INFLUENCE OF CLIMAT CHANGE ON THE BALTIC SEA COAST." In Rural Development 2015. Aleksandras Stulginskis University, 2015. http://dx.doi.org/10.15544/rd.2015.063.
Повний текст джерелаАнотація:
This paper analyzes the Baltic Sea coast measurements taken during the period between 2008 and 2015. The formation of the strip of the Northern breakwater - Giruliai during this period was influenced by the Hurricane Felix on January 10 of 2015. Describing the Baltic Sea coast strip dynamics trends, the Baltic Sea coastline change during the period between 2008 and 2015 was selected and calculated on the basis of the measurements results. Analysis of the erosive and accumulation processes of strip from the northern breakwater to Giruliai strip was provided. The carried out data of the Baltic Sea coast changes analysis show that seacoast limits are constantly changing. Reasons for the changes: swell, prevailing winds, extreme climatic events, underwater currents movement. The replenishment of the Baltic seacoast spatial data set during the period between 2008 and 2013 with the revised spatial data of the period between 2014 and 2015 showed that during the months of January during the period between 2008 and 2015 the 4 km long strip of the Baltic Sea coast (from the Northern breakwater to Giruliai) decreased by 3.7075 ha, in the Ist Melnrage area, the 0.7 km long strip of coastline has moved more than 30 m inland. It was found that in the southern half of the researched section erosional processes prevailed, while in the northern part – both erosional and accumulative ones.
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Lebedev, Alexander V., and Vladimir F. Filaretov. "The Synthesis of Adaptive Control System With Reference Model for Autonomous Underwater Vehicle." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32699.
Повний текст джерелаАнотація:
A method of adaptive system synthesis for the control of autonomous underwater vehicle spatial motion is developed. A special nonlinear correcting devices is offered. This devices allows to compensate the complete dynamical coupling and kinematic correlations between this vehicle degrees of mobility at constant control object parameters. An adaptive self-adjustment is used in order to compensate the arbitrary variations of this parameters and external perturbances. The efficiency of synthesised control system is confirmed by numerical simulation.
5
Wilson, Simson T., A. P. Sudheer, and Santhakumar Mohan. "Dynamic Modelling, Simulation and Spatial Control of an Underwater Robot Equipped with a Planar Manipulator." In 2011 International Conference on Process Automation, Control and Computing (PACC). IEEE, 2011. http://dx.doi.org/10.1109/pacc.2011.5978927.
Повний текст джерела
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Adlakha, R., M. Moghaddaszadeh, M. A. Attarzadeh, A. Aref, and M. Nouh. "A Linear Acoustic Phased Array for Nonreciprocal Transmission and Reception." In ASME 2020 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/imece2020-24237.
Повний текст джерелаАнотація:
Abstract Acoustic phased arrays are capable of steering and focusing a beam of sound via selective coordination of the spatial distribution of phase angles between multiple sound emitters. Here, we propose a controllable acoustic phased array with space-time modulation that breaks time-reversal symmetry, and enables phononic transition in both momentum and energy spaces. By leveraging the dynamic phase modulation, the proposed linear phased array is no longer bound by the reciprocity principle, and supports asymmetric transmission and reception patterns that can be tuned independently. Through theoretical and numerical investigations, we develop and verify a mathematical framework to characterize the nonreciprocal phenomena, and analyze the frequency conversion between the wave fields. The space-time acoustic phased array facilitates unprecedented control over sound waves in a variety of applications including underwater telecommunication.
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Prasad, D. H. S., S. K. Rao, B. P. Patel, and Suhail Ahmad. "Safety Assessment of Marine Structures Subjected to Underwater Explosion." In ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/omae2021-62796.
Повний текст джерелаАнотація:
Abstract The underwater explosions due to an accident or other potential reasons cause severe shocks in the fluid medium. Safety assessment is an essential design requirement where the blast load concentration is expected due to smaller standoff distances. In the present work, the probabilistic analysis of structural response due to the underwater explosion is studied using NESSUS software. The study helps improve the concepts of improved blast mitigation strategies. The shock loading considered varies spatially and temporally. The fluid pressure is transformed into structural nodal forces. Taylor’s plate theory is used to estimate the shock loading. In the analysis, the material is considered to be rate-dependent elastoplastic with temperature softening. Maximum central deflection against shock factors is obtained to arrive at the safe thickness of the stiffened and unstiffened plates for the optimum design characteristics using LS-DYNA software. The finite element approach adopted efficiently captures expected failures for various combinations of structural properties leading to an optimized design to withstand the target explosion. Johnson-Cook dynamic failure model is employed as a limit state function for reliability assessment. Sensitivity analysis enables to achieve target reliability.
Звіти організацій з теми "Underwater spatial dynamics"
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Twardowski, Michael. Mapping the Spatial Dynamics in Optically Significant Bottom Nepheloid Layers Using Autonomous Underwater Gliders. Fort Belvoir, VA: Defense Technical Information Center, September 2006. http://dx.doi.org/10.21236/ada630951.
Повний текст джерела