Naval Systems Research Articles

함정 추진체계 동적 시뮬레이션을 위한 가변추진기 수학 모델 개발

함정 추진체계 동적 시뮬레이션을 위한 가변추진기 수학 모델 개발

Characterization of sound waves propagating in a fluctuating ocean: experimental validation with ALMA

The authors present an acoustic system, designed by DGA Naval Systems, dedicated to the study of sound propagation in challenging environments. The system is called ALMA for Acoustic Laboratory for Marine Applications. Shallow and coastal waters, where oceanographic phenomena (such as linear internal waves, tides and 3-D effects) interact with acoustic propagation, represent the main area of deployments. Since 2014, 5 at-sea campaign have been successfully conducted in the Mediterranean Sea and in the Atlantic Ocean. They mainly consisted in propagating sound waves in the 1–15 kHz frequency band using fixed or towed sources towards a modular passive acoustic array. The latter is composed of 8 rigid arms carrying 16 hydrophones each. These arms can be, and actually were, arranged in various shapes, depending on the goal of the experiment. Environmental sensing using thermistor strings and CTD cast complete the experimental equipment. The analysis of the 2016 campaign demonstrates the ability of the system to gather data representative what was described as the “saturation” theory by S. Flatté in the 1980s. In fact, criteria based on the mutual coherence function and the normalized acoustic intensity probability density function allow to explain the observed variability of detection performance on a 4x32-hydrophones vertical comblike passive acoustic array. A global progress report on the use of data gathered by the ALMA system, as well as future plans—including deployment in high latitudes environments—will be discussed.

Технический облик судового глубоководного водолазного комлекса военно-морского флота с учетом требований конструктивной безопасности

Технический облик судового глубоководного водолазного комлекса военно-морского флота с учетом требований конструктивной безопасности

Failure Analysis of Metallic Components of a Battery Fitted in a Naval System

A battery based on Mg–AgCl with sea water as electrolyte was developed for propulsion of a naval system. In one occasion, the tie rod, conduit pipe and the copper bus rod each covered with polymer sleeve were found damaged. The copper bus rod was melted probably by amplified resistance and subsequent heating. Localized cross-sectional reduction (and thus increased resistance, R) seems to have aggravated heating by Joule heating (J = I2R) effect. Subsequently, it led to partial dissolution, embrittlement, softening and final fracture of the steel tie rod in the said sequence. There was no material deficiency. Chemical composition, microstructure and hardness values of the failed components indicate that the steel tie rod was made of the as-specified EN 24 type of low alloy steel in hardened and tempered condition, while copper bus rods were made of pure copper of 99.50% purity. Damage of the conduit tube was not related to the failure of steel tie rod and copper bus rod, although it indirectly offers clues that melting of copper happened and the molten copper reached many locations within the system.

Structural-Acoustic Modeling and Optimization of a Submarine Pressure Hull

<div class="section abstract"><div class="htmlview paragraph">The Energy Finite Element Analysis (EFEA) has been validated in the past through comparison with test data for computing the structural vibration and the radiated noise for Naval systems in the mid to high frequency range. A main benefit of the method is that it enables fast computations for full scale models. This capability is exploited by using the EFEA for a submarine pressure hull design optimization study. A generic but representative pressure hull is considered. Design variables associated with the dimensions of the king frames, the thickness of the pressure hull in the vicinity of the excitation (the latter is considered to be applied on the king frames of the machinery room), the dimensions of the frames, and the damping applied on the hull are adjusted during the optimization process in order to minimize the radiated noise in the frequency range from 1,000Hz to 16,000Hz. Constraints on the total amount of damping that can be used are considered (resource driven constraints) and structural collapse constraints are also taken into account in order to avoid degrading the structural integrity of the pressure hull. Two different optimization strategies are exercised. First a concurrent multidisciplinary analysis is performed; optimal configurations for structural performance and for acoustic radiation are identified and the results are used for producing a single design with optimized performance in both disciplines. Then, an analysis based on set-based design principles is performed. The latter identifies several alternative and diverse hull configurations that provide similar levels of performance with respect to the radiated noise. Having several alternative solutions of nearly equal performance provides insight into the design trade-offs when configuring the pressure hull. The results from both optimization strategies are analyzed and discussed.</div></div>

International Development and Validation of a Distributed Simulation for Naval Ship Replenishment at Sea

Navies from Canada, France, Germany, Italy, and the United Kingdom collaborated to develop and validate a distributed simulation of ship replenishment at sea. The simulation models the seaway, ship motions including hydrodynamic interaction effects between ships, and the transfer of a solid payload between ships using replenishment gear. The simulation was developed using the High Level Architecture (HLA), which facilitates sharing of data and synchronization of simulation time among software components on networked computers. Simulation results were validated using experimental data. The project demonstrated successful application of distributed simulation to complex naval platform systems. Lessons learned are shared for several areas, including seaway modelling, ship hydrodynamic interaction, and planning of model tests and sea trials for simulation validation.

Las armadas de Felipe IV. La conservación de la Monarquía

After an overview of books, articles and presentations of recent decades in naval historiography, we can observe how the situation of naval power during the reign of Philip IV was analysed from different historiographic perspectives, and how all of them offer us an incomplete knowledge today. This article seeks to understand the sea as an area of union between the territories of the Catholic King, which constitutes avital aspect to understand the idea of conservation and reputation of the Empire. These are concepts of which the contemporaries were aware and, hence, their concern to maintain a naval system capable of defending the territories of the monarchy. In addition, through the study of the armed we will analyse some factors of the complex relationship between the Court of Philip IV and the Portuguese Crown.

An Improved Underwater Confrontation Simulation Method of Naval Amphibious Operational Training System

This paper described an improved underwater confrontation simulation method of naval amphibious operational training system. The initial position of submarine forces on the enemy is generated automatically, and the attacking distance model of torpedoes is established based on the kinematics theory, which is more flexible and reasonable to judge the launch condition compared to traditional method. The two kinds of confrontation behavior models on the enemy submarine are created to depict its tactical action from the defensive to the offensive as well as the contrary, ensuring that operational style is simulated more comprehensively and properly. The existing motion trajectory estimation and collision detection algorithms on operational platforms are also improved to reduce the iteration error and further enhance the detection accuracy of target hit.

Examination of Metal-Oxidizing Bacteria and Accumulated Corrosion Products on 300 Series Stainless Steels

Event Abstract Back to Event Examination of Metal-Oxidizing Bacteria and Accumulated Corrosion Products on 300 Series Stainless Steels Treva T. T. Brown1, 2 and Jason S. Lee1, 2* 1 United States Naval Research Laboratory, United States 2 United States Naval Research Laboratory, United States The objective of this work is provide fundamental understanding of the relationship between metal-oxidizing bacteria, accumulated corrosion products and pitting in 300 series stainless steels. The 300 series stainless steel (SS) designation contains many different compositions but the common factors among them are: 18 wt% Cr and 8 wt% Ni (18-8). 300 series SS is routinely used in naval systems, e.g., fuel transfer lines. However, localized pitting on 300 series SS, especially at welds, has caused catastrophic failures of these materials. Pitting in these alloys has been investigated extensively and in most cases the failures have been diagnosed as microbiologically influenced corrosion without any demonstration of microorganisms or biomineralogy. Pitting is typically associated with tubercles or mounds of accumulated corrosion products attributed to the activities of metal–oxidizing bacteria (MOB). Tubercles on the surface of these alloys in oxygenated, chloride-containing waters causes under-deposit corrosion that initiates a series of events, leading to aggressive corrosion, i.e., fixation of a small anode surrounded by a large cathode, dissolution of metal at the anode, acidity under the tubercle and ingress of chloride. However, the structure, mineralogy and microbiology for tubercles on 300 series SS have never been examined in detail. Surface analytical techniques will be used to relate the chemical, mineralogical, electrochemical and magnetic properties of accumulated corrosion products on 300 series SS in waters containing MOB and chloride. Keywords: corrosion, Microbiologically Influenced Corossion, metal oxidizing bacteria, Biomineralogy, Stainless steel (3) Conference: National Organization for the Professional Advancement of Black Chemists and Chemical Engineers (NOBCChE) 45th Annual Conference , Orlando, Florida, United States, 17 Sep - 20 Sep, 2018. Presentation Type: Oral Presentation Topic: Enviornmental and Green Chemistry Citation: Brown TT and Lee JS (2019). Examination of Metal-Oxidizing Bacteria and Accumulated Corrosion Products on 300 Series Stainless Steels. Front. Chem. Conference Abstract: National Organization for the Professional Advancement of Black Chemists and Chemical Engineers (NOBCChE) 45th Annual Conference . doi: 10.3389/conf.fchem.2018.01.00031 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 15 Oct 2018; Published Online: 17 Jan 2019. * Correspondence: Dr. Jason S Lee, United States Naval Research Laboratory, Washington D.C., United States, jason.lee@nrlssc.navy.mil Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Treva T. T Brown Jason S Lee Google Treva T. T Brown Jason S Lee Google Scholar Treva T. T Brown Jason S Lee PubMed Treva T. T Brown Jason S Lee Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Design and Implementation of Training Management Software for General Simulation Training System

The common simulation training system realizes the common design of hardware and software, and also increases the difficulty of group training management. In order to solve the problem of flexible group training of multiple training modes for general simulation training system of a certain type of naval combat system, this paper puts forward a formal description method of group training resources and group training programs based on an in-depth analysis of training management requirements. Design and implementation of a general simulation training system training management software.

Optimal Flow Rate Control for SDN-Based Naval Systems

It is essential for a naval ship system (NSS) to transmit important information with very low delay for successful network-centric warfare under given time constraints. From this perspective, quality of service (QoS) control and low delay transmission are the most important components to improve efficient network utilization in NSSs. In general networks, conventional network algorithms have been optimized to manage network devices such as gateway, switch, bridge, hub, and router in a distributed manner for ease of plug-in and play operation, but which may not be optimal for the NSS. This is because, unlike the general network environment, the NSS is equipped with various nodes, which need to be operated through a centralized hierarchical network structure in accordance with their priorities. Thereby, it is difficult to apply new network algorithms to the NSS due to the closed network environment. To overcome this limitation, we propose a novel NSS employing software defined network (SDN) technology. A novel algorithm called real-time transmission via flow rate control (RTF) is proposed for the SDN-based NSS to optimize the specific environment of NSS. In the proposed algorithm, the optimal flow rates of nodes and network devices are obtained via dual decomposition in conjunction with requirements of delay and QoS. The proposed algorithm obtains the optimal solution iteratively while measuring the performance with traffic models based on real data measured in NSS. Through simulation using Floodlight, we demonstrate that RTF significantly contributes to improving throughput in real-time transmission compared with conventional algorithms. The proposed algorithm improves the average throughput by up to 11.8% while guaranteeing real-time transmission.

Kratki pregled značajki razvojne tehnologije idejnog rješenja za američke ratne brodove

In present study, a history analysis and review of last 30 years for U.S. naval ship concept design development trend is proposed. Based on the development of naval ship concept design model history, the three features of development process are further summarized. The first is that model-based system engineering (MBSE) becomes the basic of naval ship concept design, while the second one is that the multi-discipline crossing and combination becomes a general innovation model. And the third one is that systematization oriented naval system integration is the developing goal. Some detailed examples are presented to illustrate these three characteristics. Finally, the technology difficulties in naval ship concept design are also presented.

Using a flipped-classroom to teach shock and vibration in naval systems

A new course, Shock and Vibration, was taught at Michigan Technological University in the spring of 2017. The senior elective course in mechanical engineering was designed to give students insight into shock and vibration problems, with specific applications in naval and marine systems. The course design used a flipped-classroom approach exclusively, meaning the students watched recorded lectures prior to each class session and in-class time was used for group problem solving, quizzes, demonstrations, and discussions. A laboratory session was also included in the course. This talk will give a brief overview of the course material, cover the pros and cons of the flipped-classroom, and provide some pointers from a first-timer’s perspective.

Supporting the wartime economy: imperial maritime trade and the globalised maritime trade system, 1914–1916

ABSTRACTThe British Empire depended on international trade and financial systems for survival. These depended on general peace. The Empire could not afford extended periods of military expenditure, using civil–military and economic mechanisms to avoid the costs of an army. These demanded an efficient global maritime transport system feeding a free economic market with close industry–navy and insurance market–government–navy cooperation. These required a naval system to protect global maritime trade. The outbreak of war in 1914 stopped maritime trade, requiring rapid unprecedented government intervention to restart it. From this restart, the privately run global maritime trade system began to distort, but collapse was protracted and the commercial system showed remarkable elasticity. The imperial government progressively replaced an efficient, fluid maritime trade system based on meeting commercial demand with centralised control to meet the demands of a mobilising war economy. By July 1916 this process was complete and a remarkable example of international administration across all areas of the global and domestic economy was well advanced. The resulting centralised control of global maritime trade fed multinational economic demands of war economies: yet this broad, complex, multidisciplinary event remains largely unknown.

Designing a Framework for Target-Site Assignment in Naval Combat Management

<p>In this study, using operational research techniques, a model has been presented to assess battlefield threat, to prioritise aggressive targets, to evaluate the capability of own sites and the risks of the conflict with the targets, to define conflict scenarios and finally to select the best scenario using an assignment model. The above proceedings were added as an intermediate phase of target-site assignment, called ‘deciding the best conflict scenario’, to the ‘threat assessment’ and ‘weapon-target assignment’ in the naval combat management system. For each of the own site, the data collected from the environment together with the panels of experts are shown in a two-dimensional matrix, in which the four areas of the matrix represent the conflict scenarios. Considering that the study was done in a simulated environment, the expert’s verification and the convergence of the results in Monte Carlo method were used to validate the research. The proposed model can offer optimised decision to the operational commander through predicting the battlefield and managing the site’s capacity and the interaction in between during the combat.</p>

Experimental measurements of bubble convection models in two-phase stratified liquids

The surface flow generated by a bubble plume is a technique proposed to collect the surface-floating substances. This has a great importance when handling the oil layer formed during large oil spill accidents due to the need to protect naval systems, rivers, and lakes. The motivation of this research is to broaden the understanding of oil flow in the stratified layer of oil on the free surface. Laboratory experiments have been carried out in order to investigate the multi-dimensional motion of water and oil due to bubbles. The flow structure of bubble-induced convection in a stratified liquid is investigated by using particle imaging velocimetry (PIV) measurements and pathline measurements. It is confirmed by this paper that the flow structure is strongly modulated by the gas flow rate and bubble size. The velocity of the surface flow induced by the bubble plume in the vicinity of the oil-water interface is about 50% larger and stronger than that inside the oil layer. Moreover, the surface flow is particularly rapidly generated in the vicinity of the oil-water interface. The highest kinetic energy (which is 0.012(m/s)2) is generated at a far distance inside the bubble plume and in the vicinity of the oil-water interface. This observation confirms the idea that the bubble plume can indeed generate a strong and wide surface flow over the bubble generation system. The oil layer is easily broken by bubbles, especially with high void fraction and small bubble size and high gas flow rates. The experimental results were compared with the numerical results of our earlier paper. It is confirmed by this paper that the experimental results resemble the numerical results. As a reference, in a thermally stratified liquid, the liquid flow pattern of bubble-induced convection has also been measured by using thermo-sensitive liquid crystal tracer particles in which a color-image processing is combined to measure the temperature field. These results were compared to the immiscible stratified cases.

ABOUT THE STUDY OF ENERGY’S FLOW FROM ENERGETICALLY NAVAL SYSTEMS

In this paper are analyzed energy's flow in energetically naval systems and their correlation with the effective power of thermal machines. The possibilities for secondary energy flows recovering and their impact on the marine environment with possibilities to reduce pollution 1. INTRODUCERE In operating the plant or energy systems, a special attention must be given to mass flows and energy flows because they are main characteristic for a specific physical structure (sections flow of piping, sections of flow through thermal machines and working, sections of energetically exchanges, the components of the energy fluids, etc.). 2. MASS FLOWS

A method for track fusing using data association in naval combat system

In today battlefield multi-sensors installed on naval ship are acquiring too much information. Information is used through naval combat system to improve reaction capability to threat more quickly and precise. For acting to threat, we have to make a decision whether same ones what each target from multi sensor and execute track fusion according to result of judgment. So in this paper, we propose the track fusion method using track’s varied information. We predicted and estimated the target state based on dynamic information using data association filter so made valid measurement area what is assumed that track exists. This algorithm can set up the criterion what is adaptive current status of track. Second we selected track among existing tracks in valid area by attributing weighting. The weight considers track’s information like identification, category and so on. We would like to execute more precisely track fusion through this fusion algorithm.

Moving-Object management method of combat system using main memory DBMS

The naval combat management system conducts a comprehensive analysis of obtained information and integrates it with on-board sensors, weapons, and other equipment. Furthermore, it automatically performs all processes such as engagement plans, weapon assignments, and target detection using already pre-deployed database information. Thus, it is important to manage moving objects from many different kinds of sensors. In this paper, we will introduce the Moving-Object management method of combat systems using the In Moving Object DBMS. This is based on the main memory database technology provided by the high speed transaction processing performance.

Research on Inferring ELECTRE-III’s Parameters with Fuzzy information and A Case on Naval Gun Weapon System Integration

Multiple attributes decision making (MADM) method is an important measure for system integration. Robustness analysis on MADM is a hotspot in these years which wins academe’s great attention, and is supposed to be an effective way when countering imperfect information. Setting parameters in ELECTRE-III’s is a vital and difficult step. In this paper, a method of inferring ELECTRE-III’s parameters with fuzzy information based on robustness analysis is presented. First, ELECTRE-III is transformed into a continuous smooth function of each parameter vector. Then, robustness analysis structure and a parameters inferring algorithm are provided by maximizing robustness margin based on mathematics programming. Moreover, how to resolve the programming problem is also discussed. At last, a illustrative example of Naval Gun Weapon System Integration is put forward.