マリンエンジニアリング
Online ISSN : 1884-3778
Print ISSN : 1346-1427
ISSN-L : 1346-1427
47 巻 , 6 号
選択された号の論文の26件中1~26を表示しています
特集 船舶におけるエネルギーシフト~LNG燃料普及の可能性~
随想
解説
特集 排気規制の克服に向けた新燃焼技術の展望
随想
解説
技術資料
  • 佐古 孝弘
    2012 年 47 巻 6 号 p. 853-858
    発行日: 2012/11/01
    公開日: 2013/12/26
    ジャーナル フリー
     Many research institutes are pursuing research on homogenous-charge compression ignition (HCCI) engines, which offer higher thermal efficiency than gasoline engines at low and medium loads and produce fewer emissions than diesel engines. However, the ability of HCCI engines to operate at high loads is limited by the rate of pressure rise rate and knocking, while their ability to operateat low loads is limited by combustion efficiency.
     This article describes the basic characteristics of HCCI engines running on natural gas, and technologies for increasing their output. Natural gas has a higher ignition temperature than gasoline or light oil, generally around 1050K. Supercharging was found to be an effective way of increasing output, and a brake mean effective pressure of 0.98 MPa, thermal efficiency of 43.3% and NOx emissions concentration of13. 8ppm were obtained with a 4-cylinder gas engine.
解説
技術資料
  • Vikram Garaniya, Laurie Goldsworthy
    2012 年 47 巻 6 号 p. 871-877
    発行日: 2012/11/01
    公開日: 2013/12/26
    ジャーナル フリー
     Global shipping uses Heavy Fuel Oil (HFO) as the primary fuel. HFO is a mixture of oil refinery residue and cutter stock, hence it contains large numbers of hydrocarbons with a wide range of molecular weights and dissimilar structures. Conventional thermodynamics modelling techniques are inadequate for HFO vaporisation modelling. The present article summarises continuous thermodynamics vaporization models along with chemical kinetics models for decomposition and polymerisation, and soot burnout models, employed to study the behaviour of HFO spray combustion. A sample of HFO is also characterised in the laboratory using chemical characterisation procedures including sequential elution solvent chromatography, gas-chromatography mass spectrometry and elemental analysis, to obtain the composition and mean molecular weights of HFO fractions required for continuous thermodynamics modelling. Models are implemented via subroutines in a diesel spray simulation in the CFD package STAR-CD. The simulation is applied to a constant volume spray combustion chamber. The present model accounts for the formation and burnout of liquid phase soot in diesel engines. This soot will be emitted as Black Carbon if unburnt. The models are examined for two representative fuel samples; one with the good combustion quality and the other with poor. Good qualitative agreement is shown between the simulations and published experimental data.
解説
技術資料
論文
報告
研究室紹介
入門コーナー
feedback
Top