• 연구논문집
• /
• s.23
• /
• pp.63-71
• /
• 1993

To improve flow in-cylinder flow in a 2-valve gasoline engine, various geometries of combustion chambers are modified. Air flow rate, swirl and tumble flow are measured and analyzed by swirl impulse meter and LDV in a steady state flow measuring rig. The results of LDV experiment are compared with the data of swirl impulse meter.

• 제어로봇시스템학회:학술대회논문집
• /
• 1988.10a
• /
• pp.214-218
• /
• 1988

This paper suggests mathemathical engine model which can simulate generalized gasoline engine. Suggested engine model contains air/fuel inlet element, intake manifold, combustion, engine dynamics. In order to analyze a gasoline engine, physical characteristics of engine and steady state engine data should be controlled. In adaptation for abrupt change of circumstance or drive conditions, this model can analyze important physical phenomena in the intake manifold by computer simulation. This model can also evaluate statuses of drive under various working conditions precisely. Therfore, this model suggests basic datum to evaluate the engine system which are needed in designing and development of engine controller.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.18 no.3
• /
• pp.65-73
• /
• 2004

The bolier systems of coal fired power plants are large, non-linear systems with numerous interactions between its component parts. In the analysis of such complex systems, dynamic simulation is recognized as a powerful method of keeping track of the myriad of interactions. The boiler system consists of air/gas system and water/steam system. Due to recent reinforcement of environmental regulation on pollutant discharge and requirements of design validation on properites of boiler, the commercial programs are used for the analysis of boiler system. This paper addressed to the development of model using MMS(Modular Modeling System) developed by EPRI(Electric Power Research Institute) as the simulation tool. The developed model using MMS is tested for the design and local data on boiler combustion system of korea standard coal fired power plant boiler. The simulation results show that the developed model well reproduces responses of the combustion system with less than ${\pm}$5% error under steady state and transient state conditions. The developed model for analysis of the combustion system in this paper is general and applicable to any type of coal fired power plant.

• Journal of Hydrogen and New Energy
• /
• v.29 no.4
• /
• pp.393-400
• /
• 2018

To confirm the operating range of two oxygen carriers for chemical looping combustion system, the effects of operating variables on solid circulation rate were measured and discussed using a two-interconnected circulating fluidized bed system at ambient temperature and pressure. Moreover, suitable operating ranges to avoid choking of the fast fluidized bed (air reactor) were confirmed for two oxygen carriers. A continuous long-term operation of steady-state solid circulation more than 24 hours was also demonstrated within the operating windows. Finally we could confirm that those two oxygen carriers are suitable for chemical looping combustion system with high solid circulation rate and smooth solid circulation.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.11a
• /
• pp.111-114
• /
• 2010

MOV(Main Oxidizer shut-off Valves) control the combustion of launch vehicle systems by the supply and the isolation of liquid oxygen to a main combustion chamber in launch vehicle systems. Moreover, the MOV should secure a constant flow rate of liquid oxygen for combustion instability in the steady operational state. To modify the middle flange and rip of inlet valve design by Computer Aided Structural Analysis for improvement of EM core functions. In result, it has been verified to improve performance of EM by tests.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.1
• /
• pp.17-22
• /
• 2000

The transient process simplified by the 1-D stretched laminar flame formed at the fuel-oxidizer interface was investigated using the coherent flame sheet model. Under the combustion environment of high temperatures and pressures the results show that the time required to reach the steady state was relatively short compared to the reverse of strain rate. Hence the employment of the tabulation of precalculated steady-flame results in the calculation of turbulent diffusion flames using the coherent flame sheet model is concluded valid, Also upstream temperatures were found to have only a minor effect on the nondimensional flame temperature and nondimensional fuel even through the letter is sensitive to pressure changes.

• Journal of the Korean Ceramic Society
• /
• v.27 no.1
• /
• pp.118-126
• /
• 1990

Titanium Cabride powders were prepared by the self-propagating high temperature synthesismethod in air from the mixture of metal titanium powder and carbon powder. The result are as follows : 1. The conversion effciency of higher than 95% can be obtained and the lattice constant value of the product was 4.322$\AA$. 2. The combustion mode, velocity and temperature of combustion wave was photographed using high-speed camera, and showed steady-state, velocity of 15.414mm/sec at 250$0^{\circ}C$. 3. The relative density and MOR strength of TiC sintered at 180$0^{\circ}C$ for 90 minutes by hot-pressing under the pressure of 200kg/$\textrm{cm}^2$ were 95% and 395MPa, respectively.

• Journal of the Korean Society of Combustion
• /
• v.10 no.2
• /
• pp.18-25
• /
• 2005

An experimental study has been conducted to evaluate the effects of reburning on $NO_x$ reduction and also to examine heat transfer characteristics from LPG flame. Experiments were performed in flames stabilized by a co-flow swirl burner, which was mounted at the bottom of the furnace. Tests were conducted using LPG gas as main fuel and also as reburn fuel. The effects of reburn fuel fraction and injecting location of reburn fuel are studied. The paper reports data on flue gas emissions, temperature distribution in furnace and various heat fluxes at the wall for a wide range of experimental conditions. In a steady state, the total as well as radiative heat flux from the flame to the wall of furnace has been measured using a heat flux meter. Temperature distribution and emission formation in furnace have been also measured and compared.

• Journal of the Korean Society of Combustion
• /
• v.14 no.2
• /
• pp.18-25
• /
• 2009

Fuel lean reburning method is very attractive way in comparison with conventional reburning method for reducing NOX. Meanwhile, the knowledge of the how flue gas re-circulated, temperature distribution and species concentration is crucial for the design and operation of an effective fuel lean reburning system. For this reason, numerical analysis of fuel lean reburning system is a very important and challenge task. In this work, the effect of fuel lean reburn system on NOX reduction has been experimentally and numerically conducted. Experimental study has been conducted with a 15kW lab scale furnace. Liquefied Petroleum Gas is used as main fuel and reburn fuel. To carry out numerical study, the finite-volume based commercial computational fluid dynamics (CFD) code FLUENT6.3 was used to simulate the reacting flow in a given laboratory furnace. Steady state, three dimensional analysis performed for turbulent reactive flow and radiative heat transfer in the furnace.

• Journal of Advanced Marine Engineering and Technology
• /
• v.23 no.4
• /
• pp.543-551
• /
• 1999

Diesel engine is a major source of the air pollution. In general the concentrations of these pollu-tants in diesel engine exhaust differ from values calculated assuming chemical equibrium. Thus the detailed chemical mechanisms by which these pollutions form and the kinetic of these process-es are important in determining emission levels. In this study the computer program has been developed to calculate the required thermodynam-ic properties of combustion products(10 spacies) for both equilibrium and non-equilibrium in cylin-der for diesel engines. Nitric oxide emissions are calculated by using the extended Zeldovich Kinet-ic mechanism with a steady state assumption for the N concentration and equilibrium values used for H, O, $O_2$ and OH concentrations. By the results it is confirmed that developed simulations program with the NO prediction model is validated against residual mass fraction combustion index of Wiebe's functions pre-mixed com-bustion ration fuel injection timing.