• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.228-231
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• 2006

In general, burning time is not considered with a factor of an empirical relation on the combustion characteristic in hybrid propulsion system. So, The effect of burning time on hybrid combustion characteristics and propulsion characteristics was studied. As results, regression rate is decrease with burning time, but fuel mass flux is maintained nearly constant with burning time at given oxidizer mass flux.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.508-512
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• 2017

In this study, we carried out the study on the combustion characteristics of HTPB/AP propellants with Al and Zr as fuel metal in order to develop the solid propellant with high burning rate. The major combustion characteristics of propellant were investigated as measuring of the burning rate and pressure exponent, and the HTPB/AP solid propellants were prepared with introducing Butacene as burning rate catalyst for the enhancement of burning rate. The propellant with Al and Zr was demonstrated the improvement of propellant performance and combustion characteristic.

• Journal of the Korean Vacuum Society
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• v.19 no.5
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• pp.326-330
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• 2010

The surface oxidation of magnesium was performed by burning and PEO treatment method. The scanning electron microscopy (SEM), EDS, and I-V characteristics have been applied to the study of the oxidation status. The sample formed by buring method shows weaker corrosion-resistant property than that by PEO method, but this shows more conducting property.

• Explosives and Blasting
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• v.18 no.1
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• pp.53-58
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• 2000

Thermal analysis, analysis of combustion residue and combustion characteristics measure ment such as burning rate or temperature were carried out to clarify the combustion mechanism of a tungsten- potassium perchlorate-barium chromate chromate delay powder. The results obtained are as follows. The main reaction of the delay powder of tungsten-potassium perchlorate-barium chromate is the oxidation of tungsten by potassium perchlorate. Barium chromate acts as a burning rate modifier, and the smaller the larger is the burning rate. Three types of delay composition used in this study show characteristic burning behavior. A stoichiomertric or a oxidizer-rich composition has a small linear burning rate. although it is has a large heat of combustion. On the other hand, a tungsten-excess or a fuel-rich composition with a small heat of combustion has a larger linear burning rate than the former, showing a small fractional oxidation of tungeten (below 10%) contained in the delay powder. From these results, a surface combustion mechanism is proposed for the combustion mechanism of this delay powder.

• Journal of the Korean Wood Science and Technology
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• v.30 no.3
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• pp.18-25
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• 2002

Research to discuss the fire performance of materials requires tools for measuring their burning characteristics and validated fire growth models to predict fire behavior of the materials under specific tire scenarios using the measured properties as input for the models. In this study, burning characteristics such as time to ignition, weight loss rate, flame spread, heat release rate, total heat evolved, and effective heat of combustion for four types of wood-based materials were evaluated using the cone calorimeter and inclined panel tests. Time to ignition was affected by not only surface condition and specific gravity of the tested materials but also the type and magnitude of heat source. Results of weight loss rate, measured by inclined panel tests, indicated that heat transfer from the contacted flame used as the heat source into the inner part of the specimen was inversely proportional to specific gravity of material. Flame spread was closely related with ignition time at the near part of burning zone. Under constant and severe external heat flux, there was little difference in weight loss rate and total heat evolved between four types of wood-based panels. More applied heat flux caused by longer ignition time induced a higher first peak value of heat release rate. Burning characteristics data measured in this study can be used effectively as input for fire growth models to predict the fire behavior of materials under specific fire scenarios.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.484-488
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• 2010

In this study, combustion experiments of the End-Burning Hybrid Propulsion System using $GN_2O$(Gas Nitrous oxide)/HDPE were performed and the results were compared to those of the combustion experiments using GOX/HDPE. The regression rate of the solid fuel using $GN_2O$ is lower than that of the solid fuel using GOX since oxidizer inlet velocity of $GN_2O$ is lower than that of GOX. However, in case of using $GN_2O$, the characteristic velocity is higher than those of the GOX. The combustion chamber pressure and thrust were relatively kept constant during combustion.

• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.4
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• pp.9-18
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• 2016

In this research, the modeling of erosive burning and analysis of effective parameters were carried out for the application of fluid-structure integration analysis. The manufacture, test, and analysis of erosive burning motors were carried out to estimate the erosive burning applying Lenoir & Robillard model considering effective parameters. The erosive burning phenomenon was detected from experimental results. Erosive burning model and its effective parameters were evaluated and analyzed considering existence of aluminum in propellant, relationship among erosive burning coefficients according to characteristic length, effect of grain initial temperature. The erosive burning model was applied to the fluid-structure integration analysis, and the estimated results were close to the experimental results.

• Journal of the korean Society of Automotive Engineers
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• v.10 no.3
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• pp.60-65
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• 1988

The ignition characteristics of repetitive electric sparks into a quiescent acetylene-air premixture and LPG-argon-air premixture was investigated by using a home-made Repetitive-Spark-Generator(RSG) to elucidate the effect of fuel burning velocity to ignition ability of RSG. Results show that the optimum spark delay time interval is strongly related with fuel burning velocity, or implicitly with characteristic reaction time scale of each fuel.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.10
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• pp.1264-1270
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• 2004

In this paper research on micro solid propellant thruster is reported. Micro solid propellant thruster has four basic components; micro combustion chamber, micro nozzle, solid propellant and micro igniter. In this research igniter, solid propellant and combustion chamber are focused. Micro igniter was fabricated through typical micromachining and the effect of geometry was evaluated. The characteristic of solid propellant was investigated to observe burning characteristic and to obtain burning velocity. Change of thrust force and the amount of energy loss following scale down at micro combustion chamber were estimated by numerical simulation based on empirical data and through the calculation normalized specific impulses were compared to figure out the efficiency of combustion chamber.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1280-1285
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• 2004

Microsystem technology has been applied to space technology and became one of the enabling technology by which low cost and high efficiency are achievable. Micro propulsion system is a key technology in the miniature satellite because micro satellite requires very small and precise thrust force for maneuvering and attitude control. In this paper research on micro solid propellant thruster is reported. Micro solid propellant thruster has four basic components; micro combustion chamber, micro nozzle, solid propellant and micro igniter. In this research igniter, solid propellant and combustion chamber are focused. Micro igniter was fabricated through typical micromachining and evaluated. The characteristic of solid propellant was investigated to observe burning characteristic and to obtain burning velocity. Change of thrust force and the amount of energy loss following scale down at micro combustion chamber were estimated by numerical simulation based on empirical data and through the calculation normalized specific impulses were compared to figure out the efficiency of combustion chamber.