• Journal of the Korean housing association
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• v.17 no.2
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• pp.135-142
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• 2006

The purpose of this study is to obtain the fire safety for underground commercial space with analysing fire loads and ventilation factors. It was adopted the investigation method of field survey with commercial uses for more confidential data. The results of this study can be summarized as follows; 1) The ventilation factor shows $0.04{\sim}0.24m^{1/2}$ and it may develop ventilation-controlled fires which have much fire hazard more than fuel-controlled fires. 2) The highest value of fire load is $158.48kg/m^2$ and appeared in footwear shop which has the value $137.35kg/m^2$ for unfixed combustibles and $21.13kg/m^2$ for fixed combustibles. 3) The average value of burning rates which mean the velocity of fire development and the fire damage range is 0.143. Therefore it is desired to decrease the combustibles of compartment and is needed the method of dispersion arrangement of goods and storage to steel cabinet and so on.

• Fire Science and Engineering
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• v.18 no.3
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• pp.39-44
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• 2004

This study is intended to understand flame behavior of the pool fire. Liquid fuels were acetone, methanol, hexane and heptane which are used in many industries. Diameter of vessel was varied from 50 mm to 400 mm and the vessel was made by stainless steel and copper. Combustion time, temperature of vessel wall and heat flux of flame were measured, and flame behavior was visualized with video camera. Based on the experiment, it was found that the burning velocity and flame height was increased according to increase of vessel diameter, and vortex shedding frequency was inverse proportion to vessel diameter. And the characteristics of pool fire were affected by physical and chemical properties of liquid fuel and the vessel materials.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.3
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• pp.65-71
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• 2018

There is no significant difference in the initial viscosity of a propellant applied with yellow iron oxide and red iron oxide. In addition, the thermal decomposition rate of the material with added yellow iron oxide is faster than that with the addition of red iron oxide. Specifically, it was confirmed that the pressure exponent was 18% lower at high temperature and high pressure with yellow iron oxide than with red iron oxide. The initial viscosity was lowest at 71% of the large particle to small particle ratio.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.498-503
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• 2017

There is no unusual difference in the initial viscosity of the propellant applied with yellow iron oxide and red iron oxide. In addition, the thermal decomposition rate of the material added with yellow iron oxide is faster than that of the addition of red iron oxide. Especially, it was confirmed that the pressure exponent was 18% lower at high temperature and high pressure. The initial viscosity was lowest at 71% of large particle/small particle ratio

• Fire Science and Engineering
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• v.27 no.6
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• pp.57-63
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• 2013

This study was performed to test the combustive properties of Pinus rigida specimens treated with piperazinomethyl-bis-phosphonic acid (PIPEABP), methylpiperazinomethyl-bis-phosphonic acid (MPIPEABP), and N,N-dimethylethylene-diaminomethyl-bis-phosphonic acid (MDEDAP). Pinus rigida Plates were painted in three times with 15 wt% alkylenedi-aminoalkyl-bis-phosphonic acid solutions at the room temperature. After drying specimen treated with chemicals, combustive properties were examined by the cone calorimeter (ISO 5660-1). It was indicated that the specimens treated with chemicals showed the later time to peak mass loss rate ($TMLR_{peak}$) = (315~420) s than that of virgin plate by reduc-ing the burning rate except for $TPMR_{peak}$ (280 s) treated with DMDAP. In adition, the specimens treated with chemicals showed both the higher total smoke release rate (TSRR) (407.3~902.0) $m^2/m^2$ and $CO_{mean}$ production (407.3~902.0) $m^2/m^2$ than those of virgin plate. Especially, for the specimens treated with PIPEABP, 1st-smoke production rate (1st-SPR) (0.1250~0.1297) g/s was lower than that of virgin plate, while the 2nd-SPR (0.183 g/s) was higher. Thus, It is supposed that the combustion-retardation properties were improved by the partial due to the treated alkylenediaminoalkyl-bis-phos-phonic acids in the virgin Pinus rigida.

• Fire Science and Engineering
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• v.12 no.4
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• pp.41-49
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• 1998

In this study, the thermal improvement of an isophthalic acid polyester resin by the incorporation of flame retardants has been investigated. Aluminium hydroxide, antimony oxide and alumina powder were used to formulate the flame retardant systems. The improvement of an isophthalic resin by incorporating aluminium hydroxide is dramatic(burning rate and smoke emission are reduced), although the mechanical property is decreased significantly. The addition of small amount(2.5 phr) of antimony oxide produces high char yield(31%) which acts as a protective layer on the surface of the resin.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.3
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• pp.358-370
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• 1997

In the present study, investigations were carried out to obtain data on combustion characteristics of methane gas and hydrogen supplemented methane gas in a constant volume combustion chamber. The main results obtained from the study can be summarized as follows. The maximum combustion pressure increases as the initial pressure and hydrogen supplement rate increase, the total burning time is shorten by lowering the initial pressure and by increasing the hydrogen supplement rate. The maximum flame temperature and NO concentration increase by the initial pressure and hydrogen supplement rate increase. The flame propagation processes in near stoichiometric mixture are propagated with a spherical shape, but in excess rich or lean mixtures are propagated with a elliptical shape. And, they are changed an unstable elliptical shape flame with very regular cells by increasing the hydrogen supplement rate.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.317-320
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• 2010

In this study, the requirements for propellants to modulate the thrust of solid rocket motor were primarily investigated, followed by searching the research trends for propellants which would be feasible for the controlled solid rocket motor. And then, the theoretical performance and combustion characteristics of solid propellants being studied in ADD were demonstrated briefly.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.495-497
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• 2017

Thermoplastic propellants using thermoplastic elastomer binders show moderate performance and mechanical properties compared to thermoset propellants, but these propellants are widely used in a variety of fields due to low cost of raw materials, simple manufacturing process and stable handling process. In order to utilize thermoplastic solid propellants in various fields, we will study properties depending on the content of oxidants, metal fuels and additives.

• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.1
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• pp.15-23
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• 2019

In this study, an extinguishment model of a three-dimensional solid propellant rocket was developed by combustion and fast depressurization to control the thrust of a solid rocket. Computational fluid dynamics simulation was carried out to ascertain the change in flow patterns in the combustion chamber and the extinguishment process by using a pintle. An ammonium perchloride was used as the target propellant and the dynamic behavior of its major parameters such as temperature, pressure, and burning rate was predicted using the combustion model. The dynamic behavior of the combustion chamber was confirmed by fast depressurization from an initial pressure of 7 MPa to a final pressure of 2.5 MPa at a depressurization rate of approximately -912 MPa/s.