This paper presents some experimental results of the rate of heat release in a diesel engine using a constant volume combustion chamber.
The rate of heat release has the close relation to the shape and construction of the injected spray, the number of nozzle holes of the fuel injection nozzle. The injection quantity and the air/fuel ratio have little effects on the rate of heat release.

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By applying a smoke-wire method, the air swirl in the cylinder of the internal combustion engine was visualized successfully in the condition of motoring.
A nichrome wire coated with oil was set up inside the combustion chamber. The oil was vaporized by heating the wire electrically in the fixed instant, and then the oil vapor was cooled by ambient air and the white oil mist (smoke) was formed.
The photographs of smoke were taken by means of a high speed camera, so the flow pattern and the velocity of air were determined.
The fundamental properties of this electrically controlled smoke traces were investigated in steady flow and in the field of acceleration, and then it was found that the technique was possible to apply to the flow visualization and the quantitative measurement of the air swirl in engine.

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Up to October 1976, MaK Had no licensee for the production of MaK medium speed diesel engine in the world amd mainly sold them in the European market, however MaK has given a license for the production and sales to UBE INDUSTRIES, LTD.
This paper has descrived a brief presentation of UBE-MaK medium speed engine production program and design policy of MaK engine are discussed, for example bed plate, cylinder liner, cylinder cover and exhaust value and etc.

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It is important to control the tightening forces of high tension bolts such as the marine engine bolts. However, the direct method to measure the tightening forces of bolts practically have not been found out. So the torque control, which substitute for the tightening force control, has been widely used. But the desirable tension can't be provided with torque method. The torque method has been used not only in the marine engine plants but also in the constructions, autmobiles and power plants. Therefore direct measurements and control of the bolt tightening force are required in these industries. The ultrasonic technique is one of the most available methods.
The ultrasonic technique is based on the principles that the bolt tensile elongation and ultrasonic velocity changes are proportional to the tightening forces below the yield point of the materials. If the proportional coefficients were known, the force could be calibrated by the change of the ultrasonic propagating time in the measureing.
We have made the proto type of testing equipment and experimented on the several bolts and the testing results wre very satisfactory.

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The non-current carrying part of the marine electrical apparatus should be earthed effectively to the hull. In Japan, the cross sectional area of the earthing conductor should have 50 per-cent (min. 2mm², max. 64 mm²) as that of the current carrying conductor.
In this report, the short circuit current and the rising voltage (the contact voltage) of the non-current carrying part of the apparatus, under the line-to-ground fault condition in 3-phase 3-wire distribution system without neutral earthed are discussed. Furthermore the resistance value of the earthing conductor, which gives the contact voltage less than the safety voltage for a human body, is calculated.
Generally, the contact voltage is proportioned to the equivalent capacity between the feeder and the hull, and a little effected by the leakage resistance between the feeder and the hull. In usual merchant ship, the resistance of the earthing conductor less than 10Ω gives a low contact voltage as compared with the safety voltage for a human body.
As a practical cross-section of the earthing conductor, it's maximum value is about 14 mm², but another consideration to prevent the breaking down of the conductor caused by such as mechanical vibration and corrosion should be need. From this point of view, earthing of machinery and apparatus on ship may be completed by locking with bolts and nuts to hull directly. In conclusion, the present rules about the cross-section of earthing conductor may be seemed to request an excess value, according to the latest studies on the safety voltage for a human body.

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