[in Japanese]

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In order to apply the two-phase mist flow for the purpose of uniform and mild cooling of the high temperature walls in such advanced power systems as high temperature fuel cells, turbines and large Diesel engine with ceramic material, the cooling characteristic of the mist flow, especially the apparent large heat capacity of the coolant, is investigated experimentally in the high temperature tube and compared with the analytical results. An empirical correlation for the ratio of heat removal by impinging liquid droplet on the heating wall surface to the total heat flux was obtained from the experimental data. It is found that the ratio is mainly determind by gas Reynolds number, gas quality that means mass fraction of gas phase and the surface temperature. In the high wall-temperature range, a newly defined coefficient of the gas temperature increase was obtained experimentally and compared with the analytical results which was described in the former paper. The coefficient is found to decrease with the increase of liquid mass fraction and not to depend on the gas velocity. The tendency coincides qualitatively with that of the analytical results. The cooling characteristic of the high temperature mist flow was clarified from these considerations.

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Band spectra in infrared ranges in diesel combustion flames contain various information on intermediate or end products in the combustion process. The authors inserted an optical fiber holder into the diesel combustion chamber of DI engine, and investigated flame spectra under various conditions of injection quantities and boost pressures. Further they investigated flame spectra and flame temperature for various injection quantities and ignition timings, and made partially clear the behavior of band spectra in infrared ranges, presumably emitted from H₂O and other unidentified substances. Additionally, they confirmed existence of some unspecified absorption spectra.

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This paper denotes a study to express, with analysis of various data, in figures aging wear effects on a marine propulsion engine system under practical use now. The understanding of aging wear states of the propulsion engine system enables us to plan an efficient long-term ship's operation and maintenance schedule. In addition, the valuable research data can be applied to the basic design when building a new ship. In terms of the above-mentioned points, the auther's original objective has been almost achieved through this study.
The selected ship for the study is the Training Ship “GINGA MARU” owned by the Institute for Sea Training, Japan's Ministry of Transport. She was commissioned on December 23rd, 1972. Since then, she has been in service for a round-the-world training voyage once a year as a rule. She is equipped with a single shaft propeller driven by Mitsubisi UEC 52/105 D type, 4, 560kw×175rpm, main machinery for her 4, 888 gross tonnage.

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