• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.243-247
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• 2007

Fuel mass flux was experienced with a function of the oxidizer mass flux using initial port area of solid fuel, in stead of regression rate correlation which shows combustion characteristic in hybrid propulsion. The burning rate could be easily obtained by using the oxidizer mass flux of initial port area without iteration, and fuel configuration could be designed simply. In this experiments PE was used as fuel, COX was used as oxidizer. A variation of mass flux of solid fuel with port area is considered by changing the burning time. In the case of approximate 0.5 for an exponent of oxidizer mass flux, using the fuel mass flux correlation is more suitable than regression rate correlation in hybrid propulsion.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.189-192
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• 2010

In this study, insensitive munitions(IM) policies and technologies of advanced countries for solid rocket motor were investigated. Development trends and caseworks of each part such as propellant and motor case of rocket motor for IM were also studied. Based on these investigation and analysis for IM rocket motor, directions of the development for IM rocket motor in our country were suggested.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.91-94
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• 2007

The fabrication and firing test of the ignition system for a micro solid propellant thruster are described in the present paper. Pt igniter coil was patterned on the glass membrane that was fabricated by the wet etching process. The thickness of Pt layer was $2000{\AA}$ and the width of igniter pattern was $40{\mu}m$. The thickness and diameter of glass membrane were $15{\mu}m$ and 1 mm, respectively. Ignition test was performed. Successful ignition of HTPB/AP propellant was obtained with an ignition delay of 1.6 s at an input voltage of 12 V. The ignition energy was estimated to be 1.4 J.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.207-210
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• 2009

The AP/HTPB composite propellant is a common choice for solid rocket propulsion. The externally heated rocket via fires, for instance, can cause the energetic substance to ignite, and this may lead to a thermal runaway event marked by a severe explosion. In order to develop preventive measures to reduce the possibility of such accidents in propulsion systems, we investigate the ignition and initiation properties of AP/HTPB propellant.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.279-282
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• 2008

The AP/HTPB composite propellant is a common choice for solid rocket propulsion. The externally heated rocket via fires, for instance, can cause the energetic substance to ignite, and this may lead to a thermal runaway event marked by a severe explosion. In order to develop preventive measures to reduce the possibility of such accidents in propulsion systems, we investigate the ignition and initiation properties of AP/HTPB propellant.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1998.10a
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• pp.2-2
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• 1998

고체 추진제의 연소율(burning rate)은 연소의 동적 기동을 이해할 수 있을 뿐 아니라 추진제의 성능을 판단할 수 있는 중요한 수단이기 때문에 많은 연구가 진행되어 왔다. 특히 AP계의 고체추진제 표면에서는 발열반응인 분해반응(decomposition) 이외에도 기체로 증발되는 증발되는(evaporation or sublimation)이 존재한다. 증발반응으로 인하여 연소율은 외부압력의 변화에 대하여 반응하게 되며 실험적으로 $r_{b}$= a $p^n$의 관계를 보여주고 있다. 즉, 연소율(burning rate)은 연소실 압력 P의 n승에 비례하며 여기서 n은 실험적으로 결정되는 지수이다. 그러나 압력지수 n은 일반적으로 온도와 압력의 함수이기 때문에 실험적으로 이 측정하기는 매우 어려운 일이다. 또한 QSHOD 가정을 사용하여 고체 추진제의 연소 응답함을 해석하기 위해서 추진제의 민감계수(sensitivity parameters)에 관한 관계식이 필요하며 이러한 관계식은 추진제의 정상연소율에 관한 관계식으로부터 얻을 수 있다.다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.8
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• pp.774-779
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• 2009

A numerical modelling was performed to predict unsteady combustion processes for the AP/HTPB/Al propellant in a solid rocket motor. Its results were compared with the experimental data. Temporal pressure development was found to match quite well with measured data. A change in propellant surface was traced using the moving grid. The propellant thickness change was also observed to confirm the erosive burning effect.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.555-558
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• 2010

This paper presents a design of solid rocket motor with high length to diameter applied composite propellant. Solid rocket motor with high L/D ratio can be generated erosive burning and combustion instability on longitudinal mode. Especially, Erosive burning can effectively prolong the initial pressure spike in some star grain motors. That is, the study shows design of grain, internal ballistics and structural analysis in order to perform system requirements.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.128-130
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• 2017

$NaBH_4$ was added to improve the water reactivity of aluminum powder as a solid propellant for underwater propulsion. Aluminum powders showed different combustion characteristics depending on the amount of $NaBH_4$ added. When $NaBH_4$ was added, it was burned by reaction with water even at a temperature much lower than the boiling point. In this study, it was confirmed that $NaBH_4$ is an effective additive to accelerate the vapor reaction with Al powder.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.200-203
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• 2009

Ultrasonic techniques have the advantage of determining the burning rates with wide range of pressure in only a single test. However, ultrasonic techniques have a drawback, which is that they are using high frequency transducers and it is easily affected by noise. Therefore, ultrasonic measurement method needs noise reduction algorithm to improve or grantee accuracy of burning rate measurements of solid propellants using ultrasound. Thus, in the present study, we propose a noise reduction method of measured ultrasonic signals by applying wavelet shrinkage.