Ciencia y tecnología de buques

During the reception and / or delivery tests of a ship, vibration measurement and analysis is made to the propulsion line in order to evaluate and predict the condition of the machinery. The values taken during the measurement of the vibrations are evaluated with the acceptance criteria provided by the standards. International Standard ISO 10816-6 (1995) focuses on reciprocating machinery with power of greater than 100kW, is used by both analysts and manufacturers of propulsion machinery for ships. Through this work, we intend to evaluate the acceptance criteria of this norm in boats smaller than 100 meters. At the end of this work it is concluded that the standard must be updated, indicating and differentiating the acceptance criteria for machinery taking into account its type of anchorage to the structure (flexible or rigid), boats with length less than or greater than 100 meters and the Ship building material (Aluminum, Steel or Composite material).

Stability tests are a core part of a hydrodynamics warship design. The acquired knowledge from the hydrodynamics model basin will affect her lifespan. Particularly, a safety assessment of damaged ships, which considers environmental conditions such as waves and wind, is critical in future operations. Over the last decade, a significant amount of experience has been gained associated with predicting the capsize behavior of intact and damaged naval vessels, and the main objective of this paper is to provide insights into different relevant physical aspects to prevent the capsizing of damaged ships in waves following the Naval Ship Code (NSC) or ANEP-77 rules. Currently, the Royal Navy of Spain is developing the future F-110 frigate class and carried out model tests at Canal de Experiencias Hidrodinámicas de El Pardo (CEHIPAR) for optimizing the forms of body hulls. Among these dynamic experiences, the most critical are the damage stability tests. Although a safety criteria of damaged ships that considers environmental conditions such as waves and wind has not yet been developed, NATO and the European maritime classification societies have developed guidelines for safety assessments such as the ANEP-77. This code contains damage scenarios and environmental conditions.

In the summer of 2010, the first ever NSF’s Pan-American Advanced Studies Institute (PASI) in Colombia was held in Barranquilla and Cartagena. The two-week institute brought together researchers of the Americas to discuss topics related to dynamics and control of manned and unmanned marine vehicles. This paper presents a summary of the program organization and findings, along with lecturer and participant feedback. It is intended to serve as a lead-in to the technical papers by PASI participants contained in this special edition of Ship Science & Technology.

The 2D impact phenomenon in calm water, considering asymmetric entry and asymmetric entry withhorizontal velocity is studied. The analysis was performed by using a commercial CFD software (STARCCM+©). The results obtained from the simulations are: pressure distribution, force and roll moment.The study was carried out for typical planing boat sections. Furthermore, the critical conditions requiredfor flow separation from the keel are also determined. The results are compared with models and resultsobtained from some authors and they present very good agreement.

The 2D impact phenomenon in calm water, considering symmetric entry with vertical velocity is studied. The analysis was performed by using commercial STAR-CCM+ computational fuid dynamics software. Thee results obtained from the simulations are pressure distribution and force during impact. The study was carried out for typical planning of boat sections. The results are compared with models and data obtained from some authors and they present very good agreement.

In the naval design process, there is still no consensus on the use of 3D CAD (Computer Aided Design) systems in the early stages of design. However, the integration capability of different modules is currently making their incorporation in the initial stages more appealing. The objective of this paper is to study the early stages of design as part of the whole process and to demonstrate the convenience of using a single 3D tool during the whole project. Therefore, its impact on the whole design process will be analysed by considering the basic and early design capabilities of current CAD systems, reviewing how the main naval architecture and marine engineering demands match the features and what is the solution provided by the CAD for each case. The methodology presented offers advantages from a technical, economic and time point of view.

Navantia finished the analysis of the concept Industry 4.0 in 2016 and its application to the naval shipbuilding industry, referred to herein as Shipyard 4.0. The implementation process has begun with several projects that involved various technologies. In order to incorporate them in the new project, for naval vessels and systems, special focus has been put in the future F-110 frigate.This document aims to provide an overview of the Shipyard 4.0 model and a brief discussion regarding the projects launched for its implementation in Navantia. The initiative 4.0 is a key development vector across all the industrial sectors in the future and its expected outcomes match the ones established by the Government of Colombia in its “Plan de Transformación Industrial” (Plan of Industrial Transformation). In this context, the new frigate program (PES) is a unique opportunity to engage the local industry, in which Navantia offers its willingness to cooperate.

This research was based on the analysis of the weldability of aluminum joints, Alloy GL AW 5083 H116, with filler AWS 5.10 ER 5183 by GMAW-P process to determine the conditions of the heat-affected zone in the base material, depending on the heat input for the GMAW-P process with different pulsed technologies available in Colombia. The variables considered within this study were: welding positions (horizontal, vertical up, and overhead), type of welded joints (butt and fillet), and parameters for welding equipment (voltage, current, speed, power supply, speed development), and protective gas used (Argon, 100%). Non-destructive and destructive testing techniques were used to characterize the discontinuities found and the criteria to accept or reject the AWS D1.2 code (STRUCTURAL WELDING CODE - ALUMINUM by the AMERICAN WELDING SOCIETY). As a result, the investigation yielded the conditions for the application of filler material (ER 5183) on base material (alloy AW5083 GL H116), supported by Welding Procedure Specifications Documents (WPS) and Procedure Qualification Record (PQR) to implement in aluminum welding at the COTECMAR shipyard.

In a dynamic world of continuously evolving design and application of innovative new technologies, it is proving increasingly challenging to apply the traditional approach of prescriptive-based standards. As a result, attention has focused on the increased use of a goal based philosophy over the detailed technical standards often incorporated in rules and regulations. A successful application of this approach has been witnessed in providing goal based requirements to the design of safety for naval vessels.

Accessibility as a design concept is generally applied in land constructions; however, the medical character of the case study requires it to be considered in the design process as of its conceptual stage. The riverine ambulatory care center (RACC) is a mobile health unit to carry out medical missions in populations located on the riverbanks; given the RACC dimensions, these have limited medical services to primary care and health brigades. Physical barriers1 are the causes for an environment being inaccessible; to eliminate them, from the RACC, an analysis and redesign was performed of the conceptual proposal, based on standards for accessibility, medical spaces, and ships. Two basic moments were taken for intervention, access and interior circulation, yielding as a result the design of an integrated system of products that eliminate the physical barriers from the environment, permitting boarding and offering medical services under equal, comfortable, and safe conditions. Accessibility as modifier of the environment to improve the quality of life of users should not only be applied in medical ships, this study opens an opportunity for industry to optimize the physical environment of other types of ships by applying this concept.

This article aims to present the current and potential contributions made by the Ministry of National Defense through the Corporation of Science and Technology for the Development of the Naval Maritime and River Industry - COTECMAR - and the National Navy to the River Master Plan and to the fulfillment of the Sustainable Development Objectives defined in the United Nations Agenda 2030. To this end, the contributions that have been generated so far are explored, such as the case of the river piers, the pilot project for the River Information System (RIS) and the integration of the Small Vessels Committee that is essential for the operation of a future National Port Agency. Likewise, potential solutions that can operate to meet regional needs in health, education, transport, tourism, etc. are highlighted. Finally, the opportunity to integrate the ODS, the development plans and the River Master Plan in the structuring of interregional project portfolios focused on closing social gaps in Colombia is foreseen.

An adaptable fuzzy inference technique is being described in order to generate predictive models of the acceleration of the pitching of a high speed vessel, from the data obtained from the web on an experiment conducted by the University of Iowa. The geometry of interest in the experiment is a scale model of the type 1/46.6 of the DTMB model 5415 (DDG-51). The fuzzy algorithm for the generation of the predictive model uses a triangular partition with a 0.5 overlapping and consequents of the Singleton type. The consequents are adjusted in an automatic fashion by using recursive least squares. The algorithm shows a very low computational complexity rate which allows for it to be used for on line identification.

El trabajo presenta la caracterización mecánica y microestructural de láminas de acero ASTM A 131 grado A que conforman paneles navales (láminas reforzadas con relaciones de aspecto l/b definidas), realizada mediante ensayos destructivos, para establecer la respuesta mecánica de estructuras navales sometidas a ese tipo de cargas. Se hicieron mediciones de microdureza, tamaño de grano y ensayos de tensión a especímenes del material antes y después del impacto. El material impactado fue seleccionado de paneles estructurales sometidos a explosiones controladas cercanas generadas con cargas de 250 g de pentolita, dispuestas a distancias predeterminadas. Para la caracterización se rechazaron paneles con la presencia de fisuras. Se presentaron variaciones importantes en microdureza y características mecánicas, sin embargo, no se observaron cambios microestructurales en tamaño de grano que fueran significativos. Caracterización mecánica y microestructural de acero naval sometido a cargas dinámicas por explosión Resumen Año 1-n.° 2-vol. 1-(17-26) enero de 2008-Cartagena (Colombia) The work presents the mechanical and micro-structural characterization of the grade A ASTM A 131 steel laminate that form naval panels (reinforced laminate with defined ratios aspect l/b), attained by means of destructive testing, to establish the mechanical response of naval structures submitted to those types of charges. Measurements of micro-hardness, grain size and tension tests of specimens of the material were carried out before and after the impact. The material hit was selected from structural panels submitted to controlled explosions generated nearby with 25g charges of pentolite, placed at predetermined distances. For the characterization, panels with the presence of fissures were rejected. Important variations in micro-hardness and mechanical characteristics appeared; nevertheless, significant micro-structural changes were not observed in grain size.

Repairs and changes of steel plates in the structure of the vessels where it is possible to find steels with a high degree of deterioration need reliable welded joints in naval steel of the type ASTM A–131 Gr. A new to old. Due to the fact that the variables associated to the weldability of the materials to be repaired are not known, it is necessary to make a study on the weldability of steel ASTM A131 Gr A, in full penetration seams or junctures, under the various parameters involved in the welding process, to determine the influence of the corroding residues that affect the application of welding compounds through the analysis of the metallurgical reactions of liquid condition in order to select the contributing materials with the alloy elements that are able to prevent these phenomena and to recommend the best practices for the electric arc welding process with tubular electrode with FCAW flux core.

Last years, a medium-sized shipyard has specialized in building tankers for chemicals. This is planned to increase the production of shipyard in medium or long terms for 4-6 boats. To achieve these objectives, the changes have to be made in all kinds of services shipyard. These changes have to take place in the organization, as well as in technological areas. In the first phase of analysis, there has been a single sequence analysis of part 1, where they perform six different methods that resulted in a large number of solutions that will help restructure of shipyard.

The present work aims to analyze the Brazilian maritime industry. The core of the work is making an analysis of which are the basic elements to insert this system in the national maritime industry and how it is structured nowadays. The focus of the work is to analyze the four larger segments of this industry in Brazil: shipbuilding, construction of off-shore platforms and ship repair. The research included fieldwork in each national shipyard and other actors in the supply chain of that industry, as well as unions and associations.

Tactical Data Link (TDL) systems are a kind of Mobile Ad Hoc NETwork (MANET) used in diverse maritime operational environments such as natural disasters, surveillance, maritime search, and rescue. A TDL network is usually composed of nodes or units representing surface ships, submarines, and aircrafts able to participate in maritime operations. A routing protocol is required to establish communication between nodes, which guarantees the route from the source node to the destination node. A TDL has been developed in the Colombian Caribbean Sea (CTDL). However, no efficient routing protocol has been implemented. This works to perform a preliminary study to implement an appropriate routing protocol for the CTDL. Local environment constraints, in addition to the chosen protocols' performance analysis, will provide preliminary alternatives for a routing protocol with acceptable efficiency. This article provides a background of ad-hoc networks routing protocols, a description of the Colombian Caribbean maritime operational environment, a comparative analysis of routing protocols, and a discussion of conclusions and future developments regarding CTDL.

Integrated Logistics Support (ILS) applied in the world-class shipbuilding industry has set significant trends in the processes and life cycles of the products and/or systems developed. COTECMAR as a Countrywide pioneer company in this sector, with specific strengths in naval prototypes, has been developing actions together with the National Navy to integrate concepts related to ILS, in its processes. Therefore, a detailed analysis of how these processes are facing the requirements of such support, has become necessary, starting from the initial basis of the possible advantages and opportunities for improvement that this could bring to the corporation and the sector. This is based on the theoretical and conceptual foundations in the ILS framework and how these are developed in the company under analysis.

Antenna arrays have been used since the 1950s in multiple applications; however, it was not until recent years that, given progress in digital technologies, this application has become the fastest and most varied development in the radar world. The main motivation for their development is that they permit electronic phase steering that implies extreme phase agility, while also being tolerant to failure because of the amount of elements that comprise them. They also permit the reduction of side lobes by controlling the amplitude of each element.Because it is a currently applied technology, but with many aspects under development, it is necessary to enter this field and generate the required tools including those for computer assisted prototyping. Because of the aforementioned, this work sought to use Matlab® to create virtual prototypes of arrays that permit visualizing an approach to their real behavior stemming from certain parameters.

The diving and salvage school of the Colombian Navy offers training in rescue maneuvers, with the purpose that students acquire the skills and abilities required for effective surveillance, protection and attention of people and materials at sea that may involve dangerous situations or threaten human life. Therefore, the teaching and learning skills of student divers have to be improved. The purpose of the project is to design and build a bongo that will allow the students to effectively observe the applicability of the fundamentals of physics such as: Archimedes’ principle, Boyle’s law and Pascal’s principle, as a theoretical and practical tool that serves as effective training on rescue maneuvers in real time for students and under controlled conditions at the facilities of the Diving School of the Navy in the city of Cartagena. For its execution, exploratory research was carried out and a deductive method was applied, which began with the planning study and shipbuilding method used by COTECMAR, followed by the analysis and use of materials as a result of the experience of the Naval Base BN1 “ARC BOLIVAR” in this type of constructions. Construction manuals for rescue equipment of the United States Navy were also used as references. The existing BONGO ARC “CASA”, was used as reference and its information served as an input for naval architecture calculations and finally allowed the construction of the Bongo with the technical specifications required for training in this area of knowledge. The device was put into service for the Diving and Salvage School as a learning tool, maintaining proportional and aesthetic characteristics that provide ease, comfort, safety and efficiency during the instruction and decision-making process at a low cost and minimizing the risk of accidents

This paper describes the generation and simulation process of computational models oriented to the analysis of the operational situations (OPSIT) of anti-air warfare (AAW) and antisubmarine warfare (ASW), with the purpose of evaluating the effectiveness of different combinations of threats, weapons, and sensors of the Colombian Navy. A detailed description of the OPSITs modeling process is presented by using the selected discrete events simulation tool. The experiments design process and the statistical analysis of the results is also described, using a statistical analysis tool. All this to provide the Colombian Navy with a tool it can use to evaluate the systems that could be part of future units.

The development of ship propulsion in the areas of Economic Operation, Environmental Protection and Ship Efficiency (Triple E - Economy, Environment, Efficiency) is the comparison standard of the manufacturers of contemporary ships. The standard is based on the application of a more modern design of the diesel engines, the wide use of waste heat and the efficient operation of the ship.In accordance with the Economic Operation, the need to evaluate the design of air conditioning systems has been identified in order to determine the possible savings, which are represented by a decrease in fuel consumption, as a result of: the significant impact of this consumption in the operation of the ship, the current high costs of this energy, the periodic increase in the price of the same, and the international policies for the reduction of emissions to the atmosphere and preservation of the environment.By means of the energy diagnosis of the air conditioning system it is possible to determine the possible opportunities of energy saving during the operation of the ship.The results indicate that the thermal load and the cooling capacity required by the air conditioned spaces have a difference between their maximum and average value of 14%. This justifies the need to use a conditioning system with a variable volume of air supplied to the air conditioned space.

To find the kinematic model in applications different from robotics, the free-body diagram and coordinateconversion using Euler angles is frequently used. In robotics the Khalil-Kleinfinger (1986) method is used(and others), which allows coordinate conversions over several joints. In this paper a new application ofthis method to solve the fire control problem of a naval anti aircraft gun is proposed. To demonstrate theapplication a virtual model is built using Virtual Reality Modeling Language (VRML) and controlledby Matlab Simulink®. From the direct geometric model the solution of the problem is found, includingthe detection system, platform, gun and flight of the missile. This model serves as a tool for the design,testing and integration of controllers for the gun and detection system. The prediction algorithms ofthe trajectory of the target and the missile in flight models can also be integrated. The results show thatthe geometric model of complex systems with many degrees of freedom can be constructed in a precise,methodical and easy to understand manner.

The use of electric propulsion systems in PSVs in Brazil has recently increased, leading to be the standard for most support vessels. In those ships, the common arrangement uses high speed Diesel generator sets for power generation and induction motors driving propellers, reporting significant reductions in the fuel consumption and exhaust emissions compared with mechanically propelled PSVs. However, further abatements in these parameters could be achieved by implementing other technologies for power production. In this work, the use of medium- speed Diesel generator sets and energy storage technologies in electrically propelled PSVs is evaluated. For the above, the fuel consumption, exhaust emissions, mass, volume and acquisition costs of four arrangements are estimated and compared. Two of the arrangements are equipped with medium-speed Diesel generator sets, two with energy storage units and one with high-speed Diesel generator sets. Energy storage appears as interesting alternative for decreasing fuel consumption and emissions by optimal loading of Diesel engines. Medium speed generators also showed reductions in fuel consumption, but highest emissions. The arrangements with high-speed generators presented the lowest mass, volume and acquisition costs.

Simulation-based design increasingly replaces traditional experience-based design. This article gives an overview of techniques now used in advanced industry practice, with particular focus on navy applications. The article covers the basics of the techniques, illustrating approaches and state of the art with applications taken from the experience of Germanischer Lloyd.

Abatement of noise radiated by all kinds of vessels, and specially Underwater-Radiated Noise, because of its impacton marine life, has become the most outstanding novelty and the most dificult challenge the shipbuilding industryhas ever faced. Hence, the industry seeks to other new solutions to comply with the new guidelines and requirementsthat have been recently introduced and promoted by the EU, marine institutions, and the scientific community. "isnew topic, already studied and solved by the navies because of their strategic requirements, is now in the limelight andall the different aspects are being studied and discussed among the different players mentioned. In this new trend, theappearance of some class notations with “different limits”, assertions such as that the “propeller” is the major noise source,and the absence of consensus among the biological community about what should be the limits (for not affecting marine fauna), it is difficult to define the technological steps that should be followed. Until a consistent agreement is reached, the shipbuilding industry and the naval engineers will be “fighting against a ghost”. Within this “confusing scenario”, this paper is a clear example of how the Spanish shipbuilding industry is moving ahead to reduce the impact of new ships. The dynamic and acoustic design, developed by the authors, of the fishing research vessels “Ramón Margalef” and “Ángeles Alvariño” for the Oceanographic Spanish Institute and the experimental results obtained, in full compliance with ICES N°209 Underwater-Radiated Noise requirements, makes them reference vessels for the construction of “Silent Vessels”.

Este artículo tiene como objetivo presentar los esfuerzos que se están haciendo en el Estado de Amazonas para la formación profesional naval, desde 2004 hasta la actualidad. Teniendo en cuenta la situación de que el Amazonas está ubicado entre los más grandes polos navales de Brasil, se hace entonces necesario formar al personal para las demandas de construcción, reparación y mantenimiento de las embarcaciones fluviales en los astilleros. Las alianzas con institutos de educación profesional del gobierno, formaron técnicos en construcción naval y las alianzas con instituciones de enseñanza superior privadas y otras organizaciones no gubernamentales, buscaron formar nuevas visiones para los ingenieros y arquitectos que desconocían el mercado naval. Se presentarán en el artículo los modelos de cursos aplicados y sus respectivos focos, y los resultados de las sinergias con otras instituciones de enseñanza superior, con el mercado, con los astilleros y con los profesionales formados.

Este documento de investigación se presenta como un análisis del comportamiento histórico de compras en los proyectos de reparación y mantenimiento en la Corporación de Ciencia y Tecnología para el Desarrollo de la Industria Naval, Marítima y Fluvial – COTECMAR, más específicamente para los ejecutados en la Planta de Bocagrande. El anterior análisis, se centra en la búsqueda de aspectos que reduzcan la brecha de incertidumbre en las compras, mediante estrategias que faciliten la planeación de las compras. El modelo de investigación está basado en el análisis histórico de las compras por medio de la clasificación de los grupos y productos adquiridos en el periodo de 2015 hasta el 2020 teniendo en cuenta la clasificación ABC-XYZ, la matriz de Kraljic y los niveles de criticidad de los productos. La investigación presenta conclusiones y recomendaciones acordes a los resultados obtenidos a partir de la clasificación y selección de los materiales o productos más relevantes dentro del grupo de compras, escogidos siguiendo la ley de Pareto. Teniendo en cuenta que la línea de negocio de reparación y mantenimiento es un mercado que presenta alta incertidumbre y variabilidad, se requiere una adecuada planeación que permitan mejorar la competitividad de los servicios prestados frente a los astilleros regionales, como muestra de la efectividad de las capacidades desarrolladas por la industria astillera colombiana.

In the present study, the effect of the duct angle and propeller location on the hydrodynamic characteristics of the ducted propeller using Reynolds-Averaged Navier Stokes (RANS) method is reported. A Kaplan type propeller is selected with a 19A duct. The ducted propeller is analyzed by three turbulence models including the k-ε standard, k-ω SST and Reynolds stress model (RSM). The numerical results are compared with experimental data. The effects of the duct angle and the location of the propeller inside the propeller are presented and discussed.

This document describes the design and implementation process of an automatic failure recovery system on a tactical data link, with the purpose of increasing its reliability during the execution of command and control naval operations. is effort is part of a project that seeks to create a Command and Control System at an operational level. The design of the recovery mechanism begins with the state analysis of the data link system under study, it then, continues with the identification of possible “dead states” and finally, turns to the development of software solutions for each identified failure. is solution considers the communication infrastructure capabilities currently available in the Navy units, so its implementation costs are reduced. is paper also presents the results obtained from the tests carried out in the system, which show that the average failure recovery time was reduced by 50%, increasing the reliability of the analyzed data link.

Today’s naval ship or craft designer routinely uses the principles of human factors (ergonomics) as a way to help enhance crew performance. But even though many aspects of human factors are well known, certain important categories often remain underutilized. One of these categories is anthropometrics, the study of human body dimensions and capabilities. Anthropometrics analyzes age, gender, and other data within populations of people, such as the general population of a nation or the special population of that nation’s active duty naval personnel. For the naval designer, anthropometrics helps to ensure adequate ergonomic design for the population from which the crew is drawn. The naval designer can address in a quantifiable manner issues such as lines of sight, console height and valve handle accessibility. When anthropometric principles are thus applied, the ship better fits the capabilities and limitations of the crew, resulting in enhanced crew performance.

Unmanned Underwater Vehicles (UUVs) can be utilized to perform difficult tasks in cluttered environments such as harbor and port protection. However, since UUVs have nonlinear and highly coupled dynamics, motion planning and control can be difficult when completing complex tasks. Introducing models into the motion planning process can produce paths the vehicle can feasibly traverse. As a result, Sampling-Based Model Predictive Control (SBMPC) is proposed to simultaneously generate control inputs and system trajectories for an autonomous underwater vehicle (AUV). The algorithm combines the benefits of sampling-based motion planning with model predictive control (MPC) while avoiding some of the major pitfalls facing both traditional sampling-based planning algorithms and traditional MPC. The method is based on sampling (i.e., discretizing) the input space at each sample period and implementing a goal-directed optimization (e.g., A*) in place of standard numerical optimization. This formulation of MPC readily applies to nonlinear systems and avoids the local minima which can cause a vehicle to become immobilized behind obstacles. The SBMPC algorithm is applied to an AUV in a 2D cluttered environment and an AUV in a common local minima problem. The algorithm is then used on a full kinematic model to demonstrate the benefits.

Metamodels, also known as surrogate models, can be used in place of computationally expensive simulation models to increase computational efficiency for the purposes of design optimization or design space exploration. Metamodel-based design optimization is especially advantageous for ship design problems that require either computationally expensive simulations or costly physical experiments. In this paper, three metamodeling methods are evaluated with respect to their capabilities for modeling highly nonlinear, multimodal functions with incrementally increasing numbers of independent variables. Methods analyzed include kriging, radial basis functions (RBF), and support vector regression (SVR). Each metamodeling technique is used to model a set of single-output functions with dimensionality ranging from one to ten independent variables and modality ranging from one to twenty local maxima. The number of points used to train the models is increased until a predetermined error threshold is met. Results show that each of the three methods has its own distinct advantages.

This paper shows experimental and numerical results of three types of appendages on forward resistance reduction of displacement and semidisplacement hulls. Forward resistance results were obtained by using Computational Fluid Dynamics and towing tank tests. The appendages evaluated are stern flaps and interceptors for displacement hulls and spray railspray rails for a semiplaning hull. The experiments are independent from each other and no research was undertaken to include the combined effect of appendages on a single hull. The predicted reduction in forward resistance in all three tested devices is around 5-10%, showing potential for fuel saving through the evaluation of hydrodynamic effects of energy saving appendages.

This work is part of the development of a conceptual proposal for a 20-ton bollard pull harbor tug, for the support of vessels no greater than 7,500 tons of displacement with safety standards for port maneuvers within the jurisdictional areas of the Colombian maritime authority (DIMAR) for the Colombian Navy.The design of this vessel was focused in providing the best opportunities to take into account, because the Colombian Navy fleet will have new vessels with greater displacement by the year 2030, this growth will be require the acquisition of new tugs.The execution of this design was based on the regulation of the "American Bureau of Shipping", abbreviated ABS, complying with all the specifications and parameters of a harbor tug.The Colombian Navy units of this type are currently boats whose useful life is over 5 years, which entails unsafe maneuvering, risking human lives and the units themselves. Currently, the Navy requires new towing services to comply with its institutional mission.This project seeks to develop a conceptual design for future projects to undertake the construction of this vessel. In this way, we will be fulfill the development objectives of the Strategic Surface Force the Faro 2030 Plan.

Carbon and stainless steel, as well as Fe-Nb-Cr-W coatings were deposited on steel substrates by using electric arc spray, and its possibility of applying such coatings in the naval industry was analyzed. In order to achieve this, the coating microstructure was characterized before and after the corrosion, abrasive wear, and thermal barrier tests. Corrosion resistance was analyzed via potenciodynamic polarization test using a NaCl electrolyte at 3%; abrasive wear resistance was measured by using a three-component system following ASTM G-65 recommendations, while quality control as thermal barriers was studied by using EIS tests. Scanning Electron Microscopy, optical microscopy and X-ray diffraction were used to characterize the microstructure of the coatings.

Careers and industry tend to go hand in hand with the references that are formed throughout their history, but there are careers hidden from them, without demeriting their importance in their process and growth. The Architectural and Engineering Draughtsmen are professional technologists who are active in the Naval Industry and little is referred to them as an associated profession. However, for all those who are immersed in this industry, the work they perform and their recognition in supporting the achievement of projects in the different design and construction stages is very clear. What is really worth highlighting in them, is the growth and evolution they have taken in this industry.The times when the draughtsman transcribed ideas into drawings and plans is on the verge of extinction. Today, trained personnel is required and available to develop virtual models giving characteristics associated with the properties of each element and its integration into the total function of the project. These technologists have the experience and specific knowledge in the industry, and become the right hand of designers, engineers and builders, to develop designs from their basic stage to the closure of projects, with the confidence that they can receive alarms and ideas that make possible the completion of each job. For this reason, they take the name of designers or modelers according to the particular case of the company for which they work.

The complexity of projecting and designing a ship requires a work sequence that covers at least three main areas: (1) Concept engineering; (2) Basic engineering; (3) Detail engineering. This paper explains the design transition that exists (or should exist) between concept engineering and the final product, emphasizing the existing contractual relationship with the shipbuilder, especially in the initial definition of the project and the influence on construction aspects.

This paper takes a 2021 Argentine case to show the atmospheric and economic impacts of using LNG fueled dredgers in the second largest worldwide operation of its kind about to start in Rio de la Plata. From the emissions point of view, LNG (Liquified Natural Gas) would reduce 23%, mainly those (NOx, SOx and PM) affecting the coastal population health. The use of BioLNG would reduce 99% (60,000 Tons/yr), including as well the planetary impact of CO2 . The economic impact is estimated in savings of 14% of Dredging Cost: 665 Million Dollars (MMUsd), over the 15 years of operation. The origin of these savings is 48% Operational (reduced fuel cost) and 52% external cost mainly due to the reduced impact in Public Health Budget.

La dinámica de fluidos computacional (CFD) se ha convertido hoy en día en una herramienta importante en el proceso de diseño hidrodinámico de los buques modernos. El CFD se utiliza para modelar cualquier fenómeno relacionado con el flujo de fluidos en un volumen de control como un buque o cualquier estructura offshore en el mar. En el presente estudio se estiman los coeficientes de arrastre generados por la fuerza inducida por la corriente para una Fragata de la Armada Colombiana en aguas profundas y poco profundas mediante la aplicación de CFD, para estimar la potencia de tiro requerida en las maniobras de asistencia en muelle. El estudio muestra el proceso de simulación de los coeficientes de arrastre de la corriente del buque mediante el método de simulaciones CFD que se realiza mediante el paquete de software STAR-CCM+. Se investiga el modelo a escala de CFD del buque Fragata clase Almirante Padilla. Los resultados muestran el coeficiente de arrastre de la corriente del buque calculado, considerando una velocidad de la corriente de 1 nudo con un ángulo de incidencia de 90° para el buque a escala real. La configuración del modelo de la presente simulación se basa en el procedimiento recomendado y publicado por Lloyds Register OCIMF y en el manual UFC para la estimación del coeficiente de arrastre de corriente.

Inland navigation in shallow waters with partially submerged objects and riparian vegetation might represent severe restrictions to patrolling operations of the Colombian Navy. Consequently, there is a need for a riverine combat and reconnaissance boat with the ability to operate in 0.4 m depth shallow waters and which structural arrangement is to be designed according to maritime classification societies and operational requirements of the navy. The aim of this work is to explain and to validate the 20 knots, 3.8 tons of displacement, 8.6 m length, 2.6 m beam and 0.35 m draft boat scantling by guidelines of the classification societies and hence, improving and validating by direct analysis the hull structural arrangement.

The naval, maritime and riverine industry is one of the sectors, which has greater contribution to theworld economy, hence, quality assurance is one of the main priorities in all maritime activities, especiallythe ones related to ship building. The monitoring of different variables that allows good performance of aship involves assessing equipment in order to assure data taking with greater precision and accuracy; thisis where metrology takes place as a science for studying inherent problems to measurement data collection,focusing on equipment calibration. The grade of uncertainty produced by data taking procedures of eachequipment on board of ship depend on techniques and results control specifications, which are knownas Methods Confirmation. The metrology laboratory at COTECMAR applied this method to guaranteequality by estimating validity and reliability of the obtained results through different measuringequipment related to ship construction and repairing.

Colombia is currently searching for oil and gas at sea as new exploratory frontiers so as to incorporate new reserves. With the beginning of maritime operations comes the need for large offshore structures that allow the extraction and separation of oil and gas before transporting it to land. Most of these platforms require specific support and supply vessels, carrying a variety of loads, from liquid and bulk up general cargo, and various specific activities such as towing, rescue staff in case of accidents, firefighting and positioning anchor handling. In the offshore industry, these are known as PSV (Platform Supply Vessels). e main purpose of this work is the hydrodynamic PSV considering the environmental and operational conditions of the Colombian Caribbean including a case study.

The EU’s new “Green Policy” to reduce the environmental impact of all types of vessels is generating new Directives that shall affect the Shipbuilding Industry. As a direct consequence, an intense debate has been opened with the participation of all the players involved: the European Commission, Marine Institutions, Shipbuilding Industry, Marine Sector, and Scientific Community. Participation of the authors in the SILENV, BESST, and AQUO projects within the FP7 has permitted noticing that for the complete assessment of the ships’ environmental impact it is essential to introduce the new so-called Noise & Vibration – Full Signature indicator. In addition to the well-known topics of Noise & Vibration (N&V) on board, it includes new ones: Noise Radiated to Harbour and Underwater Radiated Noise (URN) by the ships. Both, but especially the latter (URN) became the most outstanding novelty and the biggest challenge to be technically solved. In this sense, it is essential to know the “Starting Point”: How far is the current European Fleet from the Standard Regulations and from other Directives that will soon be compulsory? And which are the technical reasons and root causes of these deviations? To address these issues within the framework of the SILENV Project, the most recent N&V database compiled with 171 ships from the European Fleet and 12,000 N&V experimental data have been assessed. It became the largest ever N&V database in the marine sector, as well as a complete novelty. Therefore, the results, conclusions and recommendations obtained from it are of paramount importance to support current policies of the EC and other Marine Institutions that focus their efforts on combating the environmental impact of the ships.

The objective of this research is to apply a dynamic maintenance model to the assets of the engineering department of a navy vessel, based on the concept of reliability engineering, which analyzes the statistics of failures of different equipment, in a period of 140 months, in order to determine which is the most sensible equipment, the failure modes and the impact it produces on the ship’s platform. This way, it is possible to focus on the problems that produce the biggest impact in the capacity of the Unit´s, in order to fulfill its roles, and this way, contribute increase its availability. This is an iterative process of continuous improvement for the maintenance plans.

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.