Hybrid propulsion and using liquefied natural gas (LNG) as the alternative fuel have been applied on automobiles and some small ships, but research investigating the fuel consumption and emissions over the total voyage of ocean-going cargo ships with a hybrid propulsion and different fuels is limited. This paper tries to fill the knowledge gap by investigating the influence of the ship mission profile, propulsion modes and effects of different fuels on the fuel consumption and emissions of the ship over the whole voyage, including transit in open sea and manoeuvring in close-to-port areas. Results show that propulsion control and electric power generation modes have a notable influence on the ship’s fuel consumption and emissions during the voyage. During close-to-port manoeuvres, propelling the ship in power-take-in (PTI) mode and generating the electric power by auxiliary engines rather than the main engine will reduce the local NOx and HC (hydrocarbons) emissions significantly. Sailing the ship on LNG will reduce the fuel consumption, CO2 and NOx emissions notably while producing higher HC emissions than traditional fuels. The hybridisation of the ship propulsion and using LNG together with ship voyage optimisation, considering the ship mission, ship operations and sea conditions, will improve the ship’s fuel consumption and emissions over the whole voyage significantly.

Mean value modelling of diesel engine combustion based on parameterized finite stage cylinder process Highlights 18 1. Mean Value First Principle (MVFP) model has been built based on Seiliger process, i.e. the 19 in-cylinder process of the engine is characterized by using parameterized finite stages. 20 2. The expressions to calculate the combustion parameters have been obtained. 21 3. MVFP diesel engine model built in this paper has been applied to the simulation of a ship 22 propulsion system. 23 4. The simulation results have shown the adaptability of the MVFP model to variable working 24 conditions and the capability of being integrated into a large system. Abstract: Mean value diesel engine models are widely used since they focus on the main engine performance and 32 can operate on a time scale that is longer than one revolution, and as a consequence use time steps that are much longer 33 than crank-angle models. Mean Value First Principle (MVFP) models are not primarily intended for engine development 34 but are used for systems studies that are become more important for engine users. In this paper two new variants of 35 Seiliger processes, which characterize the engine in-cylinder process with finite stages are investigated, in particular 36 their ability to correctly model the heat release by a finite number of combustion parameters. MAN 4L20/27 engine 37 measurements are used and conclusions were drawn which Seiliger variant should be used and how to model the 38 combustion shape for more engines. Then expressions to calculate the combustion parameters have been obtained by 39 using a multivariable regression fitting method. The mean value diesel engine model has been corrected and applied to 40 the simulation of a ship propulsion system which contains a modern MAN 18V32/40 diesel engine in its preliminary 41 design stage and the simulation results have shown the capability of the integration of MVFP model into a larger 42 system. 43

With the increasingly strict international GHG (greenhouse gas) emission regulations, higher requirements are placed on the propulsion system design of conventional ships. Playing an important role in ship design, construction and operation, ship–engine–propeller matching dominantly covers the CO2 emission of the entire ship. In this paper, firstly, a ship propulsion system matching platform based on the ship–engine–propeller matching principle and its application on WinGD 5 × 52 marine diesel engine have been investigated. Meeting the energy efficiency design index (EEDI) regulation used to calculate the ship CO2 emission is essential and ship–engine–propeller matching has to be carried out with EEDI into consideration. Consequently, a procedure is developed combining the system matching theory and EEDI calculation, which can provide the matching results as well as the corresponding EEDI value to study the relationship between EEDI and ship–engine–propeller matching. Furthermore, a comprehensive analysis is performed to obtain the relationship of EEDI and system matching parameters, such as ship speed, effective power and propeller diameter, reflecting the trend and extent of EEDI when changing these three parameters. The results of system matching parameters satisfying different EEDI phases indicate the initial value selection in matching process to provide reference for the design of ship, engine and propeller under the EEDI regulations.