Using System Dynamics to Simulate the Management of Operation and Maintenance of Ship Machinery under the Port Availability Constraints

The total cost of ship machinery operation (CT) must be kept at the minimum value while considering the safety from failure. This paper proposes a model to minimize the CT by endeavouring the value of minimum Reliability Index (RI) of the machinery. The minimum RI is the level of reliability of machinery where we need to take maintenance action after some period of operation time. The alteration of minimum RI causes the changes of the composition of CT, including running cost (Cr), maintenance cost (Cm) and downtime cost (Cd). This paper discusses the operation of pumps which are installed in the cooling system of main engine of ship. As constraint, the maintenance of the pumps is assumed only possible to be carried out in the particular available port. This study utilizes the System Dynamics (SD) to construct two kinds of proposed models of machinery operation. They are model 1, without forecasting and model 2, with forecasting of minimum RI. Model 1 results in minimum CT, while model 2 reaches a CT lower than the outcome of model 1

Fault tree analysis and artificial neural network modelling for establishing a predictive ship machinery maintenance methodology

A dynamic fault tree model for a ship main engine is developed in order to analyse and identify critical systems/components of the main engine. The identified most critical systems are then used as input in an artificial neural network. An autoregressive dynamic time series neural network modelling approach is examined in a container ship case study, in order to monitor and predict future values of selected physical parameters of the most critical ship machinery equipment obtained from the fault tree analysis. The case study results of the combination of the fault tree analysis and artificial neural network model demonstrated promising prospects for establishing a dense methodology for ship machinery predictive maintenance by successfully identifying critical ship machinery systems and accurately forecasting the performance of machinery parameters

Design for Support in the Initial Design of Naval Combatants

The decline of defence budgets coupled with the escalation of warship procurement costs have significantly contributed to fleet downsizing in most major western navies despite little reduction in overall commitments, resulting in extra capability and reliability required per ship. Moreover, the tendency of governments to focus on short-term strategies and expenditure has meant that those aspects of naval ship design that may be difficult to quantify, such as supportability, are often treated as secondary issues and allocated insufficient attention in Early Stage Design. To tackle this, innovation in both the design process and the development of individual ship designs is necessary, especially at the crucial early design stages. Novelty can be achieved thanks to major developments in computer technology and in adopting an architecturally-orientated approach to early stage ship design. The existing technical solutions aimed at addressing supportability largely depend on highly detailed ship design information, thus fail to enable rational supportability assessments in the Concept Phase. This research therefore aimed at addressing the lack of a quantitative supportability evaluation approach applicable to early stage naval ship design. Utilising Decision Analysis, Effectiveness Analysis, and Analytic Hierarchy Process, the proposed approach tackled the difficulty of quantifying certain aspects of supportability in initial ship design and provided a framework to address the issue of inconsistent and often conflicting preferences of decision makers. Since the ship’s supportability is considered to be significantly affected by its configuration, the proposed approach utilised the advantages of an architecturally-orientated early stage ship design approach and a new concept design tool developed at University College London. The new tool was used to develop concept level designs of a frigate-sized combatant and a number of variations of it, namely configurational rearrangement with enhancement of certain supportably features, and an alternative ship design style. The design cases were then used to demonstrate the proposed evaluation approach. The overall aim of proposing a quantitative supportability evaluation approach applicable to concept naval ship design was achieved, although several issues and limitations emerged during both the development as well as the implementation of the approach. Through identification of the research limitations, areas for future work aimed at improving the proposal have been proposed

Large Wind Energy Converter: Growian 3 MW

The final report on the projected application of larger-scale wind turbine on the northern German coast is summarized. The designs of the tower, machinery housing, rotor, and rotor blades are described accompanied various construction materials are examined. Rotor blade adjustment devices auxiliary and accessory equipment are examined

A modelling approach for predicting marine engines shaft dynamics

For making decisions on maintenance and operations of ship systems in a timely and cost effective way, intelligent approaches for continuously assessing the critical ship systems condition are required. This study aims to provide a framework for large marine two-stroke diesel engines performance assessment, by mapping the relationship of specific malfunctioning engine conditions on the Instantaneous Crankshaft Torque (ICT). This is accomplished by the development of a thermodynamics model, which is coupled with a lumped mass crankshaft dynamics model, in order to predict the engine shaft dynamics and torsional response. Subsequently, by employing the coupled engine models, a number of case studies are simulated for investigating the influence on the engine ICT, which include: (a) change in the Start of Injection (SOI), (b) change in the Rate of Heat Release (RHR), (c) change in the scavenge air pressure, and (d) leaking exhaust valve. By investigating the predicted ICT from the coupled model in both the time and frequency domains, distinct frequencies are identified, which correspond to specific engine malfunctioning conditions. Based on the derived results, these engine malfunctioning conditions are mapped with the frequencies most affected in the engine’s instantaneous torque, which demonstrate the usefulness of implementing the the ICT measurement for diagnostic purposes

A Hybrid Simulation Study to Determine an Optimal Maintenance Strategy

With the increasing complexity of the process industry, having excellent maintenance management is essential for manufacturing industries. Various parts that interact and interdependent with each other make a well-planned maintenance strategy is one of the major challenges facing by industry. The whole system could be interrupted just simply because of the failure of a component.  Therefore, a review of a maintenance strategy must be done from a system perspective. It is suggested that the optimal preventive maintenance time interval is not only determined by the lowest maintenance cost of each machine but also its impact on the whole system. Two main indicators that can accommodate the system perspective are reliability and revenue. A large number of machines and the array of machines can be synthesized in the reliability indicator. Moreover,  the creation of maximum revenue is always the main goal for a business. The best maintenance strategy will be determined from the revenue obtained by a process industry. The process industry discussed in this study is a flour mill which is very well known in Surabaya. This study applied a hybrid simulation to solve this problem. Monte Carlo simulation was used to observe the machine individually and the results are reviewed using the application of System Dynamics. Three improvement scenarios were proposed in this simulation study. Scenario 2 was chosen as the best scenario because it was able to generate the highest revenue at the end of the period. Scenario 2 recommends setting the preventive maintenance time interval considering resource availability

Consulting report – Servicios Industriales de la Marina (SIMA-Perú SA)

El objetivo del presente informe de consultoría consiste en la identificación de problemas dentro de SIMA-Perú S.A. y la evaluación de posibles soluciones, esta es una empresa estatal que tiene operaciones en la industria naval y metalmecánica. Cuenta con tres centros de operaciones en el Callao, Chimbote e Iquitos, este estudio se desarrolla para la sede de Callao. Se realizó un análisis exhaustivo de los factores externos e internos que afectan a la empresa, esto permitió la identificación de los problemas que la organización enfrenta actualmente. El problema que se desarrolla en este proyecto es con respecto a la insuficiente capacidad de SIMA-Perú S.A. para recibir más y más grandes embarcaciones como los buques Panamax o Post-Panamax. Las tendencias de la industria muestran que el tamaño de los buques de carga está aumentando para mejorar la eficiencia de operaciones de transporte. Las siguientes alternativas de solución fueron propuestas y evaluadas: (a) actualizar equipo antiguo y adoptar tecnología avanzada, (b) construir un nuevo dique seco, e (c) invertir en investigación de mercado. Luego de un análisis de las opciones de solución, la seleccionada es la construcción de un nuevo dique seco porque impacta directamente las causas raíz del problema, y tiene un impacto positivo y sostenible para el Perú. Para implementar esta solución, es necesario recibir fondos del gobierno, para este fin, es importante analizar el impacto de este proyecto para el país. Este estudio se centra en aspecto cualitativos, es necesario realizar una posterior investigación cuantitativa. Antes de iniciar la construcción, SIMA-Perú SA tiene que cuantificar el impacto social potencial del proyecto y obtener información de mercado para preparar un estudio de viabilidad profundo y objetivo. La solución destaca las sinergias entre los objetivos del Gobierno y la empresa. Con esto alcanzará sus objetivos de mejorar la situación económica y social de la nación, así como incrementar la actividad empresarial de la compañíaThe objective of the present consulting report involves the identification of problems within SIMA-Perú SA and the assessment of potential solutions, this company is state-owned and has operations related to the ship and metalworking industries. There are three operation centers located in Callao, Chimbote, and Iquitos. This study is developed for the Callao branch. A thorough analysis of the external and internal factors that affect the company was performed, this allowed the identification of the issues that the organization is currently facing. The problem that is developed in this project is regarding the insufficient capacity of SIMA-Perú SA to receive more and larger vessels like the Panamax or Post-Panamax ships. The current industry trends show that the dimensions of the cargo ships are increasing in order to have a higher efficiency in the transportation operations. The following solution alternatives were proposed and evaluated: (a) update old equipment and adopt advanced technology, (b) build a new dry dock, and (c) invest in market research. After an assessment of the alternative solutions, the selected one was to build a new dry dock because it directly tackles the root causes of the problem and has a positive and sustainable impact for Peru. For implementing this solution, it is necessary to receive funding from the government, for this purpose, it is important to analyze the impact of this project for the country. This study is focused in the qualitative aspects of the project, further quantitative research is required. Prior to the construction of the dry dock, SIMA-Perú SA must quantify the potential social impact of the project and obtain market data in order to prepare a deep and objective feasibility study. The proposed solution highlights the synergies between the Government and the organization objectives. It will help it reach its objectives for improving the economic and social status of the nation as well as increase the business activity for the companyTesi