マリンエンジニアリング
Online ISSN : 1884-3778
Print ISSN : 1346-1427
ISSN-L : 1346-1427
50 巻 , 2 号
選択された号の論文の31件中1~31を表示しています
特集 船舶の振動・騒音低減に関する最新技術
随想
報告
解説
技術資料
  • 山田 淳司
    2015 年 50 巻 2 号 p. 145-152
    発行日: 2015/03/01
    公開日: 2016/11/10
    ジャーナル フリー
    In recent years, electronically controlled engines have replaced conventional camshaft controlled ones for low speed marine diesel engines in order to meet both IMO NOx regulation and low fuel oil consumption (FOC). Part load or low load optimization methods (such as Exhaust Gas Bypass etc.) and/or longer stroke, high cylinder pressure engines have also been applied to meet the demands for further reduction in FOC.
    As a result, excitation forces / moments and noise emissions from engines have been increased, which makes it necessary for engine makers and ship builders to investigate vibration and noise in detail than ever before and in some cases, additional countermeasures may be necessary.
    In this paper, vibration characteristics and countermeasures for MAN B&W’s latest electronically controlled ME engines are introduced.
解説
技術資料
解説
製品紹介
解説
特集 EEDI(Energy Efficiency Design Index)/EEOI(Energy Efficiency Operational Indicator)への取り組み
随想
解説
論文
  • 関 庸之, 小島 隆志, 安藤 裕友, 千田 哲也, 香西 一樹, 島田 守
    2015 年 50 巻 2 号 p. 247-254
    発行日: 2015/03/01
    公開日: 2016/11/10
    ジャーナル フリー
    In order to verify the efficacy of antifouling paints, static raft tests were conducted using a series of test paints containing cuprous oxide concentrations of various levels from 0% to 40%. The static raft tests were carried out for 90 days at a site in Nagasaki bay in winter with non-aged test plates, and for 28 days at two sites in the Seto Inland Sea in summer, fall and winter with aged test plates. The aged test plates underwent dynamic immersion pre-treatment for 45 days under a seawater flow of 10 knots at 20°C in a dark room to simulate the actual ships’ conditions. The efficacy of antifouling paints was investigated using the relationship between fouling (animals and algae, slime) and the amount of cuprous oxide. After the end of each test, copper leaching rates for the test plates were measured for the test plates at the laboratory to verify the correlation between the fouling (sea animal species, macro algae, and slime) and the test paints containing various levels of cuprous oxide concentrations. The results showed that the degree of fouling decreased as the cuprous oxide content increased. The threshold of cuprous oxide content for macrofouling prevention was identified to be around 20% for sea animal species and around 5% for algae, while all test plates were subject to microfouling by slime.
  • Baogang Li, Katsuyuki Konishi, Tao Deng, Jun Li
    2015 年 50 巻 2 号 p. 255-261
    発行日: 2015/03/01
    公開日: 2016/11/10
    ジャーナル フリー
    In spray combustion, spray flame is formed in a position slightly away from an injection nozzle. In order to simulate spray combustion, it is important to predict precisely the distance called the flame lift-off length (set-off length). In this study, the effect of combustion conditions on the flame lift-off length was investigated using experimental results conducted with light oil and kerosene. A Single fuel spray was injected into a constant volume combustion vessel and self-ignited in high-temperature gas. Pressure, temperature, density of the internal gas, and injection pressure of the fuel were chosen as the combustion conditions considering the operation of the actual combustion equipment and engines. The combustion processes were observed with a high speed video camera. For the purpose of applying calculation models for the simulation of spray combustion, empirical formulas were derived. The formulas showed good correlation between the length and the combustion conditions. The formulas showed that the length of light oil is longer than that of kerosene only in the higher range of pressure and temperature of the ambient gas.
報告
入門コーナー
feedback
Top