• Journal of Power System Engineering
• /
• v.18 no.6
• /
• pp.113-119
• /
• 2014

Due to the development of the petroleum refining technology and continuously increased demand from markets, a quantity of gasoline and diesel oil produced from a restricted quantity of crude oil has been increasing, and residual fuel to be used at marine diesel engines has been gradually becoming low quality. As a result, it was recently reported that trouble oils which cause abnormal combustion such as knocking with extreme noise and misfire from internal combustion engines were increasing throughout the world. In this study, an author investigated ignitability and combustion quality by using combustion analyzer with constant volume(FCA, Fuel Combustion Analyzer) and middle speed diesel engine about MDO(Marine Diesel Oil), HFO(Heavy Fuel Oil), LCO(Light Cycle Oil) and Blend-HFO which was blended LCO of 1000 liters with HFO of 600 liters. Moreover, for betterment of ignitability and combustion quality of injected fuels, multi-injection experiment was carried out in the diesel engine using Blend-HFO. According to the results of FCA analysis, ignitability and combustion quality was bad in the order of MDO

• Transactions of the Korean Society of Automotive Engineers
• /
• v.9 no.1
• /
• pp.94-101
• /
• 2001

In this paper, the combustion improvement effects of alcohol-diesel oil blend fuel were investigated in a visualization engine. As a result of experiment, it was found out that the combustion chamber of deep dish type and re-entrant type at the same operation condition. However, when the con-tent of alcohol exceeded 10% of total fuel delivery, the combustion of alcohol-diesel oil blend fuel was worse than that of diesel oil. The maximum blend quantity of ethanol which is not ignited in the re-entrant type combustion chamber was estimated at approximately 40% of total fuel delivery. So, it is necessary to blend appropriate quantity of a volatility fuel such as alcohol in order to improve combustion.

• Journal of the Korean Society of Combustion
• /
• v.20 no.3
• /
• pp.21-26
• /
• 2015

This study was performed to provide the information of the combustion characteristics of n-butanol fuel in accordance with the n-heptane fuel mixing ratio. The closed homogeneous reactor model was used for the analysis. The analysis conditions were set to 800 K of the initial temperature, 20 atm of initial pressure and 1.0 of equivalence ratio. The results of analysis were compared in terms of combustion temperature, combustion pressure, CO, Soot and $NO_X$ emissions. The results of combustion and exhaust emission characteristics showed that ignition delay was decreased and the combustion temperature was increased as the n-heptane mixing ratio was increased. Also, the carbon monoxide(CO) was slightly decreased however, the soot and nitrogen oxides($NO_X$) increased a little in accordance with the n-heptane fuel mixing ratio. In addition, the pressure difference was almost the same in any conditions.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.13 no.3
• /
• pp.517-527
• /
• 1989

A theoretical analysis for the characteristics of pyrolysis and combustion of solid fuel was carried out in the present study. The hollow cylindrical combustion model including gas phase and solid fuel at inside and outside respectively was developed for the numerical analysis and parametric studies. The effects of volatile contents in the porous solid fuel and Reynolds number at inlet of gas phase on the characteristics of pyrolysis and combustion such as the radial, axial and time variations of volatile mass flux through porous solid fuel, temperature, mass fractions of gaseous fuel and oxidizer, and flame shape were investigated in the parametric studies. The results of the present study show that the flame produced by the volatiles moves to the downstream of fuel with accelerating velocity with time until extinction is occurred resulting from the completion of pyrolysis. When flame is employed with smaller amount of volatiles content in the solid fuel, the flame sheet exists closer to the inner wall of solid fuel. As Reynolds number at inlet increases, the flame sheet moves to the inner wall due to effect of convection even though the volatiles by pyrolysis increases.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.22 no.5
• /
• pp.554-563
• /
• 2016

Ships are capable of operating on residual fuel oil. Recently, various attempts have been made to meet environmental regulations and with ships operating on residual fuel oil. One way of fulfilling these requirements is by using fuel additives. Dispersants and fuel combustion improvers will have a positive effect on improving the combustion characteristics of the residual fuel oil. As such, this study examines fuel oils blended with additives by using fuel combustion analysis (FIA/FCA) and thermogravimetric analysis (TGA). The results of FIA/FCA focuse only on the amount of work done by the fuel oil. Therefore, it is recommended in this study that a new method to evaluate the combustion efficiency via FIA/FCA processes be developed. The analysis with ROHR curve gained by FIA/FCA brought similar results with pressure trace curve therefore it can be said that new analysis method can be reliable. The TGA, analysis process is very sensitive to the evaporation of fuel, for example, which could be addressed. In the performance-related findings of this study, blended samples with additives containing iron compounds showed a greater improvement in early combustion characteristics than samples without additives.

• Journal of the Korean Society of Combustion
• /
• v.19 no.2
• /
• pp.28-36
• /
• 2014

Bio fuel oil combustion experiments were successfully demonstrated at the 75 MWe oil-fired power plant without major equipment retrofit and 100% bio-fuel oil combustion was possible without big problems. The experimental data error correction was conducted and numerical model-based analysis technique was applied for the evaluation of the results. Incase of bio fuel oil combustion, heat absorption of radiative heat transfer section was reduced while convection section has opposite trend. The furnace exit gas temperature tends to rise slightly. Environment emissions such as NOx and SOx concentrations showed a tendency to decrease during the bio fuel oil combustion period. On the other hand, boiler efficiency was slightly underestimated.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.15 no.5
• /
• pp.19-26
• /
• 2011

In order to investigate the effect of fuel injection hole configuration within the scramjet combustor, experiment and quasi-one-dimensional analysis was performed. And the results were compared with experiment and analysis result which were performed in 2008 with same facility and test condition. Fuel injection hole size was decreased and quantity was increased. However the depth of fuel penetration and flow quantity of fuel were maintained. As a test result, combustion performance was increased significantly with no-cavity injector and slightly with plain-cavity. However, combustion performance with zigzag-cavity was decreased.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.11a
• /
• pp.423-431
• /
• 2010

In order to investigate the effect of fuel injection hole configuration within the scramjet combustor, experiment and quasi-one-dimensional analysis was performed. And the results were compared with experiment and analysis result which were performed in 2008 with same facility and test condition. Fuel injection hole size was decreased and quantity was increased. However the depth of fuel penetration and fuel flow were maintained. As a test result, combustion performance was increased significantly with no-cavity injector and slightly with plain-cavity. However, combustion performance with zigzag-cavity was decreased.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• v.y2005m4
• /
• pp.368-373
• /
• 2005

To achieve efficient combustion within a manageable length, a successful fuel injection scheme must provide rapid mixing between the fuel and airstreams. The aim of the present numerical research is to investigate the mixing enhancement combustion phenomena according to fuel injector location near the cavity in supersonic flow. Fuel injector location changes the actual length to depth ratio of the cavity in the supersonic combustor. Therefore fuel injector location near the cavity effects different fuel/air mixing efficiency and combustion efficiency.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2004.10a
• /
• pp.255-258
• /
• 2004

In order to provide a useful data for combustion chamber design, a numerical analysis for spray combustion of liquid fuel and oxidizer in combustion chamber has been conducted. High temperature nitrogen gas in low speed has been conveyed for the ignition of the liquid fuel and oxidizer mixture. Temperature and velocity distributions affected by characteristics of liquid fuel and oxidizer combustion have been investigated.