The rheological, ignition, and tribological properties of lubricating oils diluted with biodiesel were analyzed. The flash point tFP, calculated cetane index CCI, density ρ, coefficient of the temperature density change ε, kinematic viscosity ν, dynamic viscosity η, viscosity index VI, and lubricity during a High-Frequency Reciprocating Rig (HFFR) test (x, y, WSD, and WS1.4) and lubricating conditions during an HFFR test (oil film resistance FILM and friction coefficient μ) were determined. The test was performed for the oil mixtures of the lubricating oil of the SAE 30 and SAE 40 viscosity grades, which were diluted with the biodiesel blend (D93B7—diesel oil with 7% v/v fatty acid methyl esters, FAME) at concentrations of diesel oil in the mixture equal to 0% (pure lubricating oil), 1%, 2%, 5%, 10%, 20%, 30%, 50%, and 75% m/m, respectively. The experiment confirmed the existence of clear relationships between the increase in the dilution of lubricating oil with tested biodiesel blend and tFP, ρ, ε, ν, η, and VI, and the deterioration of lubrication conditions. It is recommended to take remedial action even in the case of low diesel oil concentration (<5% m/m) in the lubricating oil due to tFP, ν, and η changes. Simultaneously, the tests showed no significant effect on the lubricity and the CCI. The critical contamination of oil with fuel in the range of 2–5% by weight, as indicated in the literature, still allowed for a certain “safety margin” regarding these parameters. However, when the concentration of diesel fuel in the lubricating oil exceeded 5–8% m/m, the deterioration of the lubrication was expressed by a decrease in FILM and an increase in μ was observed; hence, such a contamination should be considered excessive. When the concentration of diesel fuel exceeds 10% by weight, there is a serious risk of engine damage during operation.
In general, the performance of a ship in service is different from that obtained on shipyard sea trial. Apart from any differences due to loading conditions, and for which due correction should be made, these differences arise principally from the weather, fouling and surface deterioration of the hull and propeller. The influence of the weather, both in terms of wind and sea conditions, is an extremely important factor in ship performance analysis. Consequently, the weather effects needs to be taken into account if a realistic evaluation is to be made. The primary role of the ship service analysis is a standard of performance data, under varying operational and environmental conditions. The resulting information, derived from this data, becomes the basis for operational and chartering decision. In addition, the part for the data records is to enable the analysis of trends of either the hull or machinery, from which the identification of potential failure scenarios and maintenance decisions can be derived. The traditional method of data collection is the deck and engine room log records, and this is the most commonly used method today. In terms of data processing and capabilities, this method of data collection is far from ultimate, since involves significant data distortion risk. Instrumentation errors are always a potential source of concern in performance analysis methods. Such errors are generally in the form of instrument drift or gross distortion of the reading. However, these can generally be detected by the use of trend analysis techniques. The procedure for the evaluation of the ship's service performance, that relies on proven methods of main propulsion engine service data analysis used and applied for container vessel small feeder. The vessel is equipped with indirect main propulsion, driven by means of modern medium speed engine. The different approach demonstrated to achieve the reliable and accurate main engine performance. The difference in developed engine power has been found, that corresponds well to registered sea trial results and engine retrofitting reports done, in order to limit the effective power.
Modern ships are required to increase the energy efficiency and minimize fuel consumption. This paper presents the construction, main properties and exemplary measurement results of a novel system intended for main shaft power monitoring. The telemetry system consists of the stationary part, responsible for wireless supply energy transfer to the rotating part. Additional functions of the stationery unit include radio-based, bidirectional communication with the rotating, microcontroller-based unit, and Modbus-based communication with the graphical user interface. The non-stationary (rotating) part receives the necessary energy using the wireless transmission and performs the torque and speed measurement using strain gauge and a special setup of the wireless energy system. A novel system of flexible printed circuit board (PCB) coils is used for wireless energy transmission and increases the flexibility of the device while minimizing the necessary size, weight, and costs of the setup. The microcontroller unit used for measurements allows proper sampling of highly dynamic signals and can be used for advanced drive system diagnostics or as a typical power monitoring device. Such unit was installed on a ferry and operation was monitored for several sea trips. Main results depict characteristic power data referenced to vessel speed and specific fuel oil consumption (SFOC). Proposed system construction allows to reduce system costs and provides stable readings for long period of operation.
The ship "Energy Efficiency Design Index (EEDI)" has been formulated by the IMO Marine Environment Protection Committee (MEPC) as a measure of the CO 2 emission performance of ships. The ship EEDI is calculated based on characteristics of the ship at build, incorporating parameters including ship capacity, engine power and fuel consumption. Shipping is responsible for CO 2 discharge of approximately 3.3% global emission and despite being an energy-efficient transport means, compared with other transport modes, there are opportunities for increasing energy efficiency. The EEDI requires a minimum energy efficiency level (CO 2 emissions) per capacity mile (e.g. tonne mile) for different ship type and size sectors. With the level being tightened over time, the EEDI will stimulate continued technical development of all the components influencing the energy efficiency of a ship. The paper presents an overview of EEDI calculation method for container vessels and results of experimental approach. The experimental process results through comprehensive analysis of operational data, from modern container vessel, equipped with direct main propulsion unit have been introduced. Ship operators have already been implementing energy efficiency operational measures and set goals for reducing the energy consumption of their fleet. Performance and savings are not always monitored and reported. However, it can be foreseen that such activity when is successfully promoted, reduction of CO 2 emissions can be achieved.
Environmental regulations instigated the technological and procedural revolution in shipping. One of the challenges has been sulfur emission control areas (SECA) and requirement of fuel changeover. Initially, many reports anticipated that new grades of low sulfur fuels might increase various technical problems in ship operation. This research develops a simple and easy to use method of the failure severity and intensity assessment in relation to fuel changeover. The scale of failure rate in the ship’s fuel system was evaluated qualitatively and quantitively, using developed failure frequency indicator and the time between failure. Based on 77 records of fuel system failures collected on seven ships, it has been found that frequency of failures related to SECA fuel changeover is on average nearly three times higher compared to the rest of sailing time. Their severity did not significantly change, but the structure of failures changed considerably. The method and presented results may help in improvement of ship’s systems design and on-board operational procedures.
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