Increasing environmental demands, alongside the planned penetration of natural gas as marine fuel, have rendered dual-fuel engines as an attractive prime mover alternative. In this context, knowing the specific fuel consumption is essential to selecting the most efficient engine. The specific fuel consumption can be approached by simulation models with varying levels of complexity that are either implemented by basic programming languages or simulated by dedicated packages. This study aims to develop a simplified model to predict the specific fuel consumption of dual-fuel two-stroke marine engines driving fixed or controllable pitch propellers. The model relies on clear trends approachable by polynomials that were revealed by normalizing specific fuel consumption. This model requires only the value of specific fuel consumption at a nominal maximum continuous rating to predict the engine consumption at any specified rating, including at partial engine load. The outcome of the study shows that the maximum deviations regarding the two simulated engines did not exceed −3.6%. In summary, the proposed model is a fast and effective tool for optimizing the selection of dual-fuel, two-stroke Diesel engines regarding fuel consumption.

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Building an extended architecture to eliminate boundaries to accessing and sharing data.

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There is still room to establish a methodology to optimise marine propellers, considering design requirements of the vessel, and match it to an electric motor. The method proposed herein consists in an optimisation whose objective function is power required in the electric motor shaft, and design variables are the parameters of Wageningen B-screw series propellers. A differential evolution optimisation algorithm was programmed in MATLAB environment to assess a number of propeller designs. Technical constraints of strength, cavitation, and peripheral velocity were considered. An actual ferryboat designed to operate in a lake in southeastern Brazil is proposed as the case study. The worst individual of the final population of propellers had its objective function increased by 25%, compared with the worst individual of the initial population, within only 123 s processing time. Substantially dissimilar propeller designs were found for direct and geared drive with open water propeller efficiency between 36.18 and 40.49%. The approach has shown significant gains as an early-stage design tool and highlighted the need for exploring a broad range of propellers to find the optimal motor-propeller matching.