• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.12
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• pp.1582-1590
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• 2004

The purpose of this study is to show the existence of optimal operation conditions for minimum fuel consumption of the gas turbine based combined cycle cogeneration power plant. Optimal operational condition means the optimal distribution of the power generated by each gas turbine and the heat generated by each HRSG. Total fuel consumption is calculated by the sum of the fuels for gas turbines and supplementary boiler. Fuel consumption is calculated by numerical methods of energy equations which contain the power generated from gas and steam turbines, the heat generated by HRSG and the heat extracted from high pressure steam turbine.

• Journal of Advanced Marine Engineering and Technology
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• v.6 no.1
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• pp.34-40
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• 1982

The characteristics of typical 17 kinds of fuel oils are studied to fine the calculation formulae for the required amount of air and the combustion gas amount. 1) The author's calculation formulae are as follows; (1) Theoretically required amount of air (2) Theoretical amount of combustion gas 2) Theoretical amount of the required air in combustion and combustion gas of fuel oils are always estimated less with Rosin's formula than with author's one. 3) Theoretical amount of the required air and the amount of combustion gas of fuel oils are more reasonable with author's formula than Rosin's one in comparison with results of actual analysis.

• 한국전산유체공학회:학술대회논문집
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• 2003.08a
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• pp.219-224
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• 2003

An analysis procedure for the MCFC channel flow has been developed to predict the fuel cell performance. As for the electrochemical reaction, among several chemical reaction models, one that fits the data best is adopted after a comprehensive comparative study. The Wavier-Stokes, energy, and species equations are solved to obtain the velocity, temperature and concentration fields for a specified average current density. The procedure is iterative as the local current density, or the reaction rate, is allowed to vary with the gas composition. A series of calculations are then carried out to examine the effects of gas flow rate, gas composition, gas usage rate, inlet gas temperature, and average current density on the fuel cell performance. The fuel cell characteristics, such as the temperature, current density distributions, and the concentration fields, for various operating conditions are presented and discussed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.2 s.257
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• pp.125-131
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• 2007

This paper presents guideline for a practical design of the hybrid system combining a pressurized solid oxide fuel cell and a gas turbine. Design of the hybrid system based on a virtually designed gas turbine was simulated using models for off-design operation of the gas turbine. Two system configurations, with different method for supplying reforming steam, are considered and their design characteristics are compared. A higher design cell temperature provides better system performance. However, there exists a maximum allowable design cell temperature because the operating point of the compressor approaches the surge point with increasing fuel cell temperature. Increased pressure loss at the fuel cell moves the compressor operating point toward the surge point and reduces system performance.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.885-890
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• 2006

This study presents analysis results for the hybrid system combining solid oxide fuel cell and gas turbine. Two different system layouts(an ambient pressure system and pressurized system) are considered and their design performance are comparatively investigated taking into account critical design factor, the most critical parameter such as turbine inlet temperature, gas turbine pressure ratio, temperature difference at the fuel cell and fuel cell operating temperature are considered as design constraints. Performance variations according to system layout and design parameters are examined in energetic view point.

• 한국연소학회:학술대회논문집
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• 1999.10a
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• pp.129-138
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• 1999

In this paper, our main issue is that establishing the control procedure of continuous gas flow rate according to combustion fan RPM. For this, first, we decide the optimum operating condition of gas swirl burner through analysis of combustion characteristics - thermal efficiency, combustion efficiency and exhaust gases such as CO, $CO_{2}$, $O_{2}$, $NO_{x}$ and THC. Second, fuel gas flow rate of gas valve is decided with considering excess air ratio and combustion fan RPM is decided by the target of combustion air flow rate. Finally, experimental operating equation is acquired by regression for gas valve and combustion fan. This equation is the control equation of continuous gas flow rate and always gas flow rate is decided by combustion fan operating RPM.

• Journal of the Korean Institute of Gas
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• v.13 no.1
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• pp.28-33
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• 2009

Natural gas is the world's most plentiful combustible fuel, abundantly acailable in all continent. A fuel injector designed specifically for low energy density gaseous fuels has been developed. The injector incorporates design features that are necessary to optimize the performance for fuels such as CNG, LNG. Gaseous fuel injectors have a decisive influence upon starting performance, driveability, fuel consumption and exhaust emissions. A gaseous fuel injector has been developed to cope with the considerably larger volume flow rates and the developed gaseous fuel injector could be used at heavy duty natural gas engine. The static flow of injectors at various inlet pressure was directly proportional and the controllability showed great performance.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.293-298
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• 2011

The combustion and flow-rate control characteristics of fuel-rich gas generator which could be adopted to Ducted Rocket propulsion system are investigated. The gas generator is designed considering the design requirements of propulsion system and solid fuel for fuel-rich combustion is developed then adopted to ground test. The results of combustion test show the necessity of the special analysis tool for estimating the gas generator performance where multi-phase flow of fuel-rich gas exists. During the flow-rate control test, characteristics of gas generator pressure with the angle of valve are analyzed and, method to estimate the pressure of gas generator is suggested using the relation between the valve exit area and discharge coefficient.

• Journal of ILASS-Korea
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• v.24 no.4
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• pp.194-202
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• 2019

A mixture preparation strategy was proposed and evaluated in a diesel-natural gas dual-fuel engine to reduce hydrocarbon (HC) and carbon monoxide (CO) emissions under low load conditions. An experimental investigation was conducted in a single-cylinder compression-ignition engine. Natural gas was supplied with air during the intake stroke, and diesel was injected directly into the combustion chamber during the compression stroke. First, effects of diesel start of energizing (SOE) and natural gas substitution ratio on the combustion and exhaust gas emissions were analyzed. Based on the results, the mixture preparation strategy was established. A low natural gas substitution ratio and a high exhaust gas recirculation (EGR) rate were effective in reducing the HC and CO emissions.

• Journal of Korean Society for Atmospheric Environment
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• v.14 no.2
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• pp.107-116
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• 1998

Coal gasification fuel has generally a lower calorific values than natural gas and also contains ammonia which is a main source of fuel NOx. Such a fuel is in need of the advanced technologies for the NOx reduction with higher combustion efficiency. Therefore fuel staged combustion was investigated for the fuel NOx control using a bench scale gas combustoi for the fuel NOx control. Parametric screening studies were performed with the variation of air ratio, retention length and reburning fuel. The NOx reduction efficiency was increased with an increase of total air ratio having optimum reburning air ratio differently, The Increased retention length of the reburning zone was preferable for NOx reduction. Hydrocarbonic reburning fuels like propane and butane were more effective for the NOx reduction efficiency than hydrogen fuel. The NOx concentration at exit was linearly increased according to the fuel-N the fuel.