Recently, almost all the shipping and related companies are required to correspond to the management innovation due to the increase of the fleet scale, the decrease of Japanese crews and engineers, and multi-nationalities of the superintendent and ship crews. And also it is required to take countermeasures against the organization management composed of aged staff and the technical and know-how transfer to the young staff.In the present situation, more effective information to the customers and exact engine monitoring system for optimum operation are necessary at anytime and anywhere, to keep the ship's schedule and to realize a high reliability of transportation. From the standpoint of the customer, MES has developed a concept of ' Performance and Maintenance Diagnosis Service for Marine Diesel Engines via Internet '. This applies state of the art Information and Communication Technology and has been offering the service since November, 2004. The basic concept, strategy, service menu, contents, results and future plan of the service are described here.More than 1,300 members have now joined the service of Mitsui-MAN B&W main engines. The useful information and data has been accumulated since then, so that MES will be able to offer a more useful and effective service, not only utilizing such information and data but also applying new useful service.
The New Berthing Support System (NBSS) will enable position fix-accuracy to within 10cm. It is global and is an effective system to assist LNG tankers, VLCC and other dangerous goods carriers for their safe berthing and entering/leaving port. The system consists of an on-board, maritime mobile station and a base station shore-side. A major function of the mobile station is to record data, sound the alarm on such as course deviation, the monitoring of the velocity component and the position of an object vessel. The major function of the base station is in the management of safe navigation, and to transfer weather at sea information and alike to the mobile station
We performed an ecological risk assessment on antifouling paints that contain copper pyrithione (CuPT) which are applied to vessels visiting Tokyo Bay. The Margin of Exposure (MOE = NOEC/EEC) method was used in the risk assessment, with the NOEC set to 0.25μg/L (Skeletonema costatum Growth inhibitor). The EEC was estimated by using a chemical fate model developed at AIST. The Uncertainty Factor (UF) was set to be 100 for this ecological risk assessment. The calculation period was for year 2008, when antifouling paints containing TBT will be substituted for alternative paints, such as those containing CuPT.In this study, the ecological risk was found to be significant because the MOE values were below the UF in the commercial ports of Yokohama, Tokyo and Chiba, but not throughout the entire study area.In Tokyo Bay, the ecological risk posed by CuPT in antifouling paints is at its greatest in the Yokohama port area. In a bid to reduce this risk, we estimated potential reduction in CuPT concentration in high MOE area, such as Yokohama port. This, by the effects of dispersion using water flow and by enhancing photodegradation.
Reduction of CO2 is the world's greatest problem right now, the demand on shipping is clear. However, there are limits to improvements with regard to ship form or the engine, itself. The authors have so far engaged in research for an environment-friendly solar boat, and propose hybridization of a ship from the extension.In this paper, the effects of hybridizing are predicted; using operational records, of such as the small fishing boat which cruises the neighborhood of the Suou Oshima, and training ship "Oshima-maru" of the Oshima National College of Maritime Technology.
The prevention of air pollution from ships has been much discussed at the IMO over the years. As a result, MARPOL Appendix VI was established and took affect in May 2005. The regulation is enforced for five years and it will be reviewed again. For the application progress purpose, the 12th Conference on Bulk Liquids and Gases [BLG 12] was held on February 2nd - 4th, `08 at London. The execution time for a concrete numerical value of the 2nd and 3rd regulation has been agreed. The 3rd regulation is mainly concerning a decrease of the emissions on NOx, SOx and PM (Particulate Matter). The regulations impact on the economic aspect in the treatment process must also being considered. Authors have undertaken research of exhaust gas treatment system for pollution from ships by applying the advanced technology of seawater scrubber. The exhaust gas and waste water treatment system with high reliability and safety devices has been developed to remove particulate matter (PM) and poly-hydrocarbon compounds (PAHs). In a testing stage, the removal rate of NOx, SOx and PM from diesel engine shows the effective value of 80%.
Regulation of sulfur used in marine fuel regulation for the prevention of marine pollution by ships.This is being discussed on the Marine Environmental Protection Committee of the IMO (International Maritime Organization) MEPC BLG. [Sub-committee: Bulk Liquids and Gases.] Proposals were determined on MEPC57 held in London and adopted at MEPC58. In this report the background to the proposals, and the oil companies response to them, are explained.
Effects of Injection pattern on Emission formation process of a D.I. Diesel engine with a total in-cylinder sampling system were investigated. While keeping the injection pressure and total injection quantity constant, a ratio of amounts of fuel injected between two injection pulses and the injection interval were varied. The concentration of smoke and NOX emission were measured at different crank angles to obtain in-cylinder histories of these concentration products and the in-cylinder pressure was analyzed. The emission formation processes were discussed with the combustion processes and the result of the engine experiment. The results account for the effect of split injection pattern on the combustion and emission characteristics.
A series of experiments were performed on a circulating fluidized bed (CFB) in order to investigate effects of the rolling motion on gas-solid flow in the CFB. Rolling period, superficial velocity, solids circulation flux, and particle size were changed in the experiments, while the amplitude of the rolling motion was maintained at ±16deg. The following results were obtained: (1)When the CFB stands upright, the gas-solid flow regime in the riser are affected by the superficial gas velocity and three types of flow regimes were observed: Bubbling fluidization, Turbulent fluidization, and Fast fluidization. (2)The solids circulation flux also affects gas-solid flow of the CFB at upright attitude. As the solid ciculation flux becomes larger, the total pressure drop throughout the CFB increases. (3)When the CFB undergoes the rolling motion, downflow of particles along the riser walls periodically changes, and falling particles accumulate on the distributor. As a result, total pressure drop throughout the CFB under rolling motion becomes larger than that of the upright attitude. (4)In our experiment, the rolling period has no influence on the total pressure drop throughout the CFB in the rolling motion. (5)When the superficial velocity is sufficiently large, the gas-solid flow in the riser is not affected very much by the rolling motion. And the total pressure drop throughout the CFB in rolling motion becomes nearly the same as that at the upright attitude.
The greatest difficulty on ships in recent years is to decrease the environmental impact of the exhaust from Diesel engines. For this, it is necessary to improve the combustor efficiency to suppress the fuel input rating, and to suppress the generation of various poisonous substances. One of the most effective method is to optimize the fuel injecting timing. Using a hydraulic servo valve, we can boost fuel pressure before injection, and starts injection at the best timing for effective combustion. Another method is to keep a high pressure in a fuel oil tank and control the starting and stopping of fuel injection with a solenoid valve, which is attached on the injection valve. The first system has proved too expensive because it uses the high price servo valve. The application of the latter system is thought to be limited to small engines, such as cars. This is because a high speed and large capacity electromagnetic valve are required. This research proposes a new composition for a simple, cheap and efficient fuel injection system with a Direct Drive Volume Control actuator. With this system we attempt to improve fuel costs and improve exhaust properties. This is achieved with optimizing injection pressure and injection timing to the operating condition.
Revolution control in the marine diesel engine is accomplished with a governor, and an electro-hydraulic type has become conventional these days. Thus performance of the governor has improved so much, but it is complex, and some trouble can be expected. We are developing a new type of electro-hydraulic governor, one using a direct drive volume control hydraulic system. It has been installed aboard the training ship of TUMSAT "Shioji-Maru." By this paper we introduce our newly developed "Electro-Hydraulic engine Governor" which has the direct drive volume control hydraulic system. We continue to study the effects, for the reeducation of fuel consumption in Marine Diesel Engines.
When a little fluctuation of the revolutions on a marine propulsion diesel engine might be accepted, its fuel consumption rate would be reduced without any modifications to the engine. In the process of developing a new type engine governor, it was found that an insensitive diesel engine revolution control can get lower fuel consumption than a sensitive one. However, an insensitive governor will course some trouble such as "Over speed trip" of the engine during operation in rough seas. The fluctuation of revolution on marine propulsion engines are caused with hull movements, especially pitching motions, which have strong effect. Considering those facts, the idea that to estimate the pitching motion in near future and apply it to the control of an engine's revolutions came to our mind.This paper is introducing a new algorism for the engine governor that is how to get a lower fuel consumption rate with preventing over-speed without any modifications to the engine itself. These effects of the new algorism were confirmed with using the training ship "SHIOJI MARU" in Tokyo University of Marine Science and Technology.Newly developed this "DDVC Governor" has the function of on-line change for any parameters with using digital controller. And it proved that the confirmation of effects of new algorithm for engine governor was quite easy.
In a combined system of the diesel and gas engine, the EGR method can easily be designed to reduce total NOx emission in the system, such as with LNG ships. The problem of the EGR system is the high PM concentration that causes some engine troubles. This can be reduced by mixing the exhaust gas from a gas engine into the intake air of a diesel engine. The EGR ratio was limited at 17% of the intake oxygen concentration, and without an increase of PM and CO. The system can be designed in full consideration of the displacement of both engines for practical use.
Dimethyl ether (DME) is one of the most promising alternative fuels for the near future. For rapid spread, it is desirable to use the mixture of DME with LPG (mainly propane), because a mature supply infrastructure already in existence can be employed. However, using the mixture of LPG and DME as a fuel for a spark ignition engine causes a problem, knocking during combustion. In a previous study, the authors analyzed this knocking phenomenon by a three-dimensional combustion simulation based on a chemical kinetic model using a GTT-CHEM code. This code was constructed by linking the authors' GTT code to the CHEMKIN-II code. In this study, using this simulation technique, the authors have investigated the effect of combustion chamber shape on the knocking phenomenon. The authors have explored a new combustion chamber which can suppress this occurrence of knocking. A small gas engine for co-generation system was employed and obtained experimental data, for comparing with the numerical simulation results.
The Ronchi-ruling is a grating, with lines, spaces and small pitches of spatial frequency. This is used in the Ronchi test for the evaluation of surface flatness. In this study, a new type of velocimeter, using a Ronchi-ruling, was proposed and its performances were investigated. When the stripes of laser light through a grid of the Ronchi-ruling illuminated the tracer particles moving with the flow, the scattered light signal could be obtained as a wavy signal of light intensity. This signal was detected with a photomultiplier. Frequencies of the obtained signal were measured by an FFT analyzer. The flow velocity was calculated from the grid pitch and the frequency. This method was applied to the measurement of velocity profiles of pipe flows. The profiles measured by this velocimeter agreed with theoretical profiles of the laminar and turbulent flows.