In recent years, there is a shortage of skilled technicians in various manufacturing industries which has been a problem. Retraining of technical staff in design aspects and business aspects of machinery design and fitting is vital to the survival of all manufacturers especially those in ship building. IHI MARINE UNITED has started to tackle this issue in order to modernize its technical design department.

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Needs of high-speed mass data communication for vessels have risen world wide. In June 2003, a discussion concerning Earth Station on-board Vessels (ESV) was made during the Committee of WRC-03. Since the earth station having access to the satellites of C-band and the Ku-band Fixed Satellite Service (FSS), it enables the satellite communication to operate for ship services. Especially, since Ku-band has expanded its services, which supports compact equipment smaller than C-band and has been operated for FSS over the world. In this article, the outline of antenna system for Ku-band support ESV broadband is described. The developed antenna is a small antenna system with 0.6 aperture diameter and 46dBW as EIRP that fulfill ESV technological standard requirement.

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This paper describes fundamental characteristics of high frequency induction heating applied for Marine Fuel Oil (MFO) recovery system. The system is analyzed for an induction heating load, related to operating frequency and input power. Frequency domain characteristics of load equivalent circuit parameters in induction heating are investigated to clarify an effective circuit design of the high frequency power supply. Furthermore, the effectiveness of a high permeability ferrite gum mat on the induction heating unit to improve the heating efficiency of the induction heating system is experimented and elucidated. The practical connection method of working coils is examined. On the basis of these fundamental characteristics, MFO filled in the large scale oil tank is simulated as the sunken ship is successfully heated up by the high frequency induction method.

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This paper describes a high frequency power supply for Particulate Matter (PM) reduction system. In the proposed reduction system, to reduce the PM emission from diesel engine, PM in the exhaust gas is burned using the induction heating unit. In this reduction system, when the metallic filter is heated up to high temperature, each value of inductance and resistance of the filter change in accordance with rise of temperature. In this paper, high frequency power supply and its control method are proposed for the PM reduction system, in which metallic filter can be heated up higher than Curie temperature. As the result by analysis, it is shown that not only an adjustment of temperature of the metallic filter at steady state but a control for a power supply to maintain stable operation even if circuit parameters are changed at the transient state of heating is enabled with Pulse Width Modulation (PWM) .

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Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI) released the world's first liquid nitrogen-cooled superconducting motor in January 2005. In April IHI released the world's first full superconducting motor. The process of the development of these and the technical breakthrough, and the features of each motor are discussed. The introduction of the large full superconducting motor that will be developed in the future are also described.

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A particulate matter (PM) reduction system exhausted from marine diesel engine has been investigated on the basis of high frequency induction heating technique. The proposed PM reduction system employs two sets of induction heating units made of diesel particulate filter (DPF) and they are operated alternately to regenerate the metallic filter parts. The metallic filter generates heat with an eddy current when a high frequency current is supplied to the working coil to heat the filter to a temperature of at least 600°C. Then the particulate matter trapped by the filter is burned out. The improved structure of the DPF is introduced and experimented using a diesel engine generator. The effectiveness of the DPF system is verified through the experiment.

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The Temperature Monitoring and Alarming System (T-MAS) is a unique system which can detect scuffing on the running surface of the cylinder liner of large two-stroke diesel engines before the occurrence of excessive wear. An excessive wear of cylinder liner has a very high impact on the vessel schedule and operating cost.
T-MAS detects the symptom of scuffing on the surface of cylinder liner by monitoring temperature. Normally, there is enough cylinder lubricating oil on the surface of cylinder liner. When the scuffing is started on the very small local part, cylinder lubricating oil has gone by the metal-to-metal contact and combustion gas with high temperature blows on this part. At that time, the temperature behavior of this surface is unique. Therefore, ship operators can avoid the excessive wear by taking a proper countermeasure when T-MAS detects such phenomenon.

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The maximum combustion pressure (Pmax) tends to increase in a diesel engine. This leads to the cylinder head gasket sealing being exposed to tough conditions which can result in gas leakage. In this study, the main factors affected by the rise in Pmax are analyzed and also from perspective of treatment orientations not only for cylinder head gasket but also total sealing engine are proposed.

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The amount of sulfur in fuel directly affects the emission of SOx from diesel engines. It also has an effect on the engine performance and emissions of PM, NOx and others. The object of this study is to investigate the influence of sulfur concentration in a medium-speed engine, which is being used as a main engine or dynamo engine in a lot of ships. The fuel used is of the high sulfur containing substance DBDS (Di-tert-butyl Di-sulfide) at various rates in the same “A” heavy oil. The following results were obtained. As the amount of sulfur concentration increases, the brake fuel consumption ratio increases, causing increase of SO₂, decrease of NOx and no change of CO₂, O₂ and CO. ISF increases almost linearly, and though SOF shows a upward tendency at low load, it does not change at normal 75% load. Therefore PM which is the sum of ISF and SOF increases through 25 to 75% load.

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To clarify the mechanism of turbulent combustion from a view point of physical data, premixed turbulent combustion in a constant volume combustion chamber was researched. Flame shape was measured as cross sectional image by laser sheet method. The most suitable method for extraction of flame front was examined and flame shape was evaluated as complexity of flame outline by fractal dimension. The results showed that the image processing method using frequency filter was suitable for extraction of correct flame front. Fractal dimension of flame shape was increased by turbulence intensity. Furthermore it was kept constant value at each turbulence intensity during growth of flame.

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