The combustion of W/O emulsion (emulsified heavy oil A with water particles) has been investigated in a high speed direct injection diesel engine. In this experiment, by color high-speed cinematography, the combustion process was revealed for both emulsion and heavy oil A in combustion chamber. This made it possible to characterize the difference of combustion behaviors between such two kinds of fuels. As the results of the study, the effects of emulsion on the combustion process, such as the ignition delay, the spreading flame and the combustion period were clarified. And under the same experimental conditions for high-speed cinematography, the engine performance and exhaust gas emissions were also presented for both fuels.

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Due to the strong demands for energy saving and improved habitability of ships, design of propellers with higher efficiency and lower cavitation induced excitation is recognized to be most impotant, together with matching of the propeller with the given engine and ship performances.
Under these circumstances, MHI developed propellers with integrated performances called MAP (Mitsubishi Advanced Propellers), together with a new stainless type propeller material called MCRS (Mitsubishi Corrosion Resistance Steel), intending not only improved performances but also reduced propeller weight.

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In a departure from the hitherto - prevalent practice of driving large turbchargers with the axial turbine, a MET-SR series of trubochargers, 30SR, 33SR, 42SR, 53SR, and 66SR, newly developed by Mitsubishi are driven by a large-size radial turbine, each being designed capable of meeting the engine ratings of about 1500PS to 14, 200PS. The new series features an improved performance particularly in the low-load and medium-load ranges, while retaining all the design excellences of the preceding MET-SC series, e.g., non-water-cooled gas casings, inboard bearing system, slide bearing, etc. Principally the performance and structural features of the MET-SR series are herein outlined.

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The geometrical features of marine gate valves have been specified in JIS-F. Recently, they are going to be modified based on the International Standard (ISO) . The distances between two flange faces of the gate valves is shortened in the ISO Standards which may cause to reduce its structural rigidity.
This paper presents the deformation characteristics of the marine gate valves in ISO standards which are analyzed by the three - dimensional finite element method. The analysis draws to, the following results:
(1) Based on the deformation characteristics, the structure of the marine gate valve can be modelled by the composite structure consisting of the cylindrical and rectangular shells with flanges at each edge.
(2) The bonnet flange considerably reduces the deformation of the valve body.
(3) The performance for shutting off fluid flow, defined by Eq. (1) in this paper, of ISO valves is sperior to other gate valves, which are in the market in Japan and U.S.A., with size 2-24B
(4) The ribs connecting the bonnet and vertical flanges effectively increase their structural rigidity.

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In this standard, tolerances of dimension, fit, and surface roughness of the main parts of the propulsion shafting are specified. Items of the main parts are intermediate shaft, propeller shaft, shaft coupling, coupling bolt and nut, stern tube, stern tube bearing, propeller boss and bonnet of the propulsion shafting whose propeller shaft diameter is 200mm or more and whose stern tube bearing is oil lubricated type and whose propeller is keyless type.

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