• 한국군사과학기술학회지
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• 제22권1호
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• pp.35-41
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• 2019

Ferrocene and ferrocene derivatives have been widely used as a burning rate catalyst for composite solid propellants. However, its tendency to migrate through the propellant grain and to crystallize at the surface changes the composition of propellant which results in unpredictable burning rate. To overcome the weakness of ferrocene catalyst, we designed a polymer containing ferrocene, poly(glycidyl azide-co-glycidyl ferrocenyl ether) (GAFP). GAFPs were synthesized from poly(epichlorohydrin-co-glycidyl ferrocenyl ether) (PEGF) which has ferrocenyl ethers in its pendant groups. The structures of GAFPs were confirmed by FT-IR, $^1H$ and $^{13}C$ NMR spectral analyses. Thermal properties of the GAFPs were evaluated using differential scanning calorimeter (DSC). As the contents of ferrocene increased, the glass transition temperature ($T_g$) of the GAFPs shifted to a higher temperature, and the decomposition temperature ($T_d$) decreased because the ferrocene worked as a burning rate catalyst.

• 한국추진공학회지
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• 제25권4호
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• pp.12-18
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• 2021

본 연구에서는 추력 제어용 추진제 조성 개발을 위해 고 압력지수 추진제를 만들고자 하였다. 프리폴리머로 PCP를 사용하며 니트라민 계열의 산화제인 HMX와 HNIW 기반 추진제를 제조하여 각각의 연소특성을 비교하였다. HMX에 비해 HNIW가 추진제의 연소속도, 비추력 그리고 화염온도에 큰 영향을 준다는 것을 알았다. 또한, AP를 조 산화제로 사용할 경우, 추진제의 연소속도, 비추력 및 화염온도는 미세 AP 함량, 총 고체 함량 그리고 가소제 양이 증가할수록 병행 상승하였으나, 압력지수는 오히려 낮게 나타났다. 그리고, 여러 압력 구간에서 온도에 따른 연소특성 변화를 알아보기 위해 150 psia부터 2,500 psia사이 구간에 대해 PCP/Nitramine/AP 추진제의 연소속도에 대한 온도 민감도를 측정하였다.

• Journal of Mechanical Science and Technology
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• 제15권4호
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• pp.473-481
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• 2001

By depicting the transfer of heat and combustion reaction to take place within thin gas layers close to the propellant surface burning in a steady-state fashion, a mathematical equation has been deduced to describe the burning rate of solid propellant as a function of initial grain temperature and chamber pressure. It has been also assumed that chemical reaction could take place in premixing-diffusing zone but were carried out mainly in the reaction-flame zone. All these phenomena taken place in each zone of combustion have been assumed to be steady-state. In the present investigation, the equation, γ=$\kappa$$.$(1/R(T(sub)i+C))(sup)n$.$exp(-E(sub)a/R(T(sub)i+C))(P/z) is being presented and it is compared with experimental data. The proposed model has been tested and evaluated vis-a-vis strand burner data for three different propellants based on CTPB, and it has been found that the deviation of the computed burning rates from the measured rates ranged up to 2%.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제27회 추계학술대회논문집
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• pp.228-231
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• 2006

일반적으로 하이브리드 추진 연소 특성에서 연소 시간은 실험식의 인자로 고려되지 않는다. 따라서 실험의 변수로써 연소 시간이 하이브리드 연소 특성 및 추진 특성에 미치는 영향에 관하여 연구하였다. 후퇴율은 연소 시간에 따라 감소하나, 연료 질량 유속은 일정한 것으로 나타났다.

• 한국추진공학회지
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• 제21권2호
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• pp.18-25
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• 2017

무노즐 부스터에 사용하는 추진제의 연소특성에 관한 연구를 수행하였다. 밀도비추력을 향상키기기 위하여 고체 추진제의 조성에 Al와 Zr의 금속연료들이 도입되었으며 무노즐 부스터를 설계하기 위하여 낮은 압력지수 및 고 연소속도가 추진제의 주요 연소특성으로 연구되었다. Zr을 함유하는 추진제는 Al을 함유하는 추진제보다 높은 연소속도를 보였으며, $13{\mu}m$ Zr을 함유하는 추진제는 연소속도는 35 mm/s (at 1000 psi)와 압력지수 0.3282를 보였다. 이러한 결과로부터, 무노즐 부스터에서 Al와 Zr을 함유하는 추진제를 사용하는 이점을 보였다.

• 한국안전학회지
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• 제7권3호
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• pp.73-82
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• 1992

This paper was concerned with the risk evaluation of oxidizing substances by burning test method. The samples were prepared the heaped cone-shaped mixtures of solid oxidizing sub-stance with sawdust, and ignition of the sample was made on contact with heating wire inside the combution chamber that the temperature and humidity of atmosphere can be kept at $25^{\circ}C$ and 60% respectively. Accordingly, it were measured the combustivity effect of mixing ratio and amount of sample weight on the burning rate. As a result of burning test of these samples, it could be noticed that the case when the sawdust has so and 30 wt.% in the mixing ratio shows effective combustivity, and as the amount of sample weight was increasing, It showed more rapid burning time. So the average burning time could be obtained by considering the weighting factors to the parameters of the mixing ratio and the amount of sample weight. Finally, it was compared with the effects of cation and anion of oxidizing substances and also applied analytically to the classification and evaluation of oxidizing sub-stances as dangerous goods.

• 한국추진공학회지
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• 제13권2호
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• pp.17-25
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• 2009

본 연구에서는 연소실의 축방향 압력과 속도변화를 고려한 비정상 내탄도 해석모델을 제안하고 이를 바탕으로 침식연소에 미치는 인자를 해석하였다. 개발 모델의 검증을 위하여 침식연소가 없는 경우와 침식연소가 있는 경우에 대하여 선행연구 결과와 비교하였으며 해석결과가 일치함을 확인하였다. 연소실 압력, 그레인 길이, 그레인 초기온도, 추진제 기화온도가 침식연소에 미치는 영향을 조사하였다.

• 한국연초학회지
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• 제26권2호
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• pp.117-125
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• 2004

In this study, we have investigated the natural and puffing combustibility of cigarette brands and the compulsory ash-drop, and analysed factors related to the materials. Cigarette combustibility was greatly affected by the tobacco weight in cigarettes rod. Combustion rate of 4AOR cigarette made by flue-cured tobacco was 5.02 $^{mm}/_{min}\;and\;10\%$ faster than 1BO cigarette. Combustion pattern has interrelation with sugars, chlorine and ash contents among tobacco components. Combustion rate of 4DL, flue-cured tobacco was 55 seconds faster than 1CL tobacco extremely much in sugars contents, and ash drop was maintained at $21\%$ longer. Combustion time and burning rate were fast in cigarette made by expanded tobacco slice and tobacco stem and the formation of ash was poor. The length of puffed ash drop of expanded tobacco slice and tobacco stem were 18.6 mm and 25.2 mm and these forced ash drop length were 3.8 mm and 4.9 mm respectively. Puffed burning rate of general cigarette was $14.3\%$ faster than static burning rate and super slim type cigarettes was $21.3\%$ faster. Combustion rate and ash drop of domestic and foreign cigarette brands were quite different depending on tar level and cigarette types. The lower tar level, the faster combustion rate and the shorter ash drop.

• 대한기계학회논문집B
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• 제20권1호
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• pp.244-254
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• 1996

Flow velocity was measured by, use of hot wire anemometer. Turbulence intensity was in proportion to mean flow velocity regardless of swirl velocity. And integral length scale has proportional relation with swirl velocity regardless of measurement position. Turbulent burning speed during flame propagation which was determined by flame photograph and gas pressure of combustion chamber was increased with the lapse of time from spark and was decreased a little at later combustion period. Because of combustion promotion effect, turbulent burning speed was increased according to increase of turbulence intensity. Burning speed ratio i.e. ratio of turbulent burning speed ($S_BT$) to laminar burning speed ($S_BL$) was found out by use of turbulence intensity u' and integral length scale $l_x$ , $\delta_L$ is width of preheat zone in laminar flame.

• 한국표면공학회지
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• 제53권1호
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• pp.15-21
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• 2020

In this study, growth and burning behavior of 6061 aluminum alloy was studied under constant anodic voltages at various temperatures and magnetic stirring rates in 20% sulfuric acid solution by analysing I-t curves, measuring thickness and hardness of aluminum anodic oxide (AAO) films, observations of surface and cross-sectional images of AAO films. AAO films were grown continuously at lower voltages than 18.5V but burning occurred when a voltage more than 19V was applied in 20% H₂SO₄ solution at 20±0.5℃ and 200 rpm of magnetic stirring. The burning was always related with an extremely large increase of anodic current density with anodizing time, suggesting that high heat generation during anodizing causes deteriorations of AAO films by chemical reaction with acidic solutions. The burning resulted in decreases of film thickness and hardness, surface color brightened and formation of porous defects in the AAO films. The burning voltage was found to decrease with increasing solution temperature and decreasing magnetic stirring rate. The decreased burning voltages seem to be closely related with increased chemical reactions between AAO films and hydrogen ions.