To study the effect of fuel viscosity, injection pressure and surface tension on the mean droplet size and spray angle, the diesel fuel spray droplets were measured by a Laser diffraction technique. Several kinds of glycerine solution with water and residual fuel oil were used. The tests were carried out over a wide range of injection pressure [3 to 90 MPa (30.6 to 917.7 kgf/cm²) ] and of kinematic viscosity of liquid [1×10^-6 to 200×10^-6 m² /s (1 to 200 cSt) ] at ambient pressure of 3 MPa (30.6 kgf/cm²) .
The main results obtained are as follows:
(1) Sauter mean diameter increases with increasing kinematic viscosity of liquid, but decreases with increasing injection pressure. There are an upper limit of viscosity and a lower limit of the pressure to produce a fine spray.
(2) At high injection pressure, the effect of viscosity on Sauter mean diameter still remains, but the viscosity has no effect on the spray angle.
(3) When the viscosity is the same at low injection pressure, Sauter mean diameter of glycerine solution spray is larger than that of residual oil. Surface tension has no effect on the Sauter mean diameter at high injection pressure.

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The authors have been undertaking theoretical and experimental studies to reduce the specific fuel consumption of diesel engines. These studies are:
1) Improvement of cycle efficiency through the variation of parameters involved in the high pressure cycle related to the combustion process, and in the low pressure cycle related to the intake and exhaust process, including the turbocharger system.
2) Improvement of mechanical efficiency through the reduction of friction and other losses. As a result of these studies, the “E-Series” engines were developed which have a specific fuel consumption that is 7-15% lower than that of the conventional engines.
Further studies were conducted to increase the thermal efficiency of the “E-Type” engine using simulation. The results indicate the possibility of reducing the specific fuel consumption by an additional 7%.

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This paper is an excerpt from the manuscripts written by the two subcommittees, i.e., the Bioler Subcommittee and the Reciprocating Engine Subcommittee, of the Marine Engineering History Committee of the MESJ. The manuscript was completed after 10 years of hard work, but has not yet been published because of various adverse conditions. This paper is the first of the serial papers which will appear in this Journal twice a year to introduce the content of the manuscript to members of MESJ.
The history of western style marine engineering and shipbuilding in Japan started in the last 15 years of the feudal Tokugawa Age, which was succeeded by the Meiji Era. The Tokugawa Government hired Dutch and French consultants, constructed Nagasaki and Yokosuka Shipyard by importing all tools and machineries from abroad, and constructed its navy. The Meiji Government that succeeded inherited nearly all of them, and eagerly constructed navy and mercantile marine under a new system. The first half of the Meiji Era, from 1868 to 1893, had seen a very rapid development of marine engineering and shipbuilding technology. After reviewing the preceding Tokugawa era, this paper describes the rise of western style shipping and shipbuilding in Japan in this period. Two tables on the propulsion machinery installed in home-made and imported new ships are given. The rapid progress is the result of the cooperative effort of the government and the industry.

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Regarding with recent tendency of high viscosity and low quality of marine fuel oil by petroleum refining plants, improvement and development of fuel treatment equipment and system become inevitable for marine diesel engines.
The new filter was developed as simple and low cost no back flushing dynamic driving filter to cope with residual heavy fuel oil.
This report gives its characteristics and application test results by ocean going vessel.

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Nippon Kokan K.K. has developed a simulation system for the main engine coolant temperature control process.
This simulation system consists of a process simulator and a control panel fitted with the process controllers, and has the functions which make it possible to operate them as the same condition as the cooling system runs actually.
According to the functions, this simulation system can be used for the following purposes:
(1) Training of unexperienced workers for the adjusting technique of the process controllers.
(2) Pre-adjusting the process controllers for the building ships and the reduction in time for on-board tests.
(3) Training of the ship operators.
This system was set at Tsurumi Works in Nippon Kokan K.K. in August 1984 and sufficient results were obtained through the applications to several ships.

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