• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2012.05a
• /
• pp.201-212
• /
• 2012

In general solid propulsion offers cost effective, large thrust capabilities comparing to the liquid propulsion which offers high specific impulse and restart capabilities. Therefore solid propulsion is well fitted for the first stage and boosters. BBL approach has been studied for the launch vehicle because of cost effectiveness, limited development time and low risk. Using of the carbon fiber epoxy resin in the solid rocket motor case is expanded, and specially high strength fibers are more attracted since its inert mass reduction.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2002.10a
• /
• pp.33-33
• /
• 2002

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2011.04a
• /
• pp.249-252
• /
• 2011

고체로켓추진기관의 추력조절을 위해 핀틀 기술이 사용된다. 아직까지 핀틀 유동에 대해 근본적인 물리적 이해를 돕는 연구가 공개되지 않아, 이 연구에서 다양한 형상의 needle형 핀틀에 따른 유동구조에 대한 수치적 연구를 진행하였다. 2차원 축대칭, 압축성을 고려하여, 상용 열유체 해석 프로그램인 FLUENT 6.2를 사용하여 해석을 수행하였다. 난류 모델을 검증하기 위해 기 수행된 실험 결과와 비교하였다. 핀틀 각도(tip angle)가 작아질수록 노즐에서 유동 박리점이 하류로 이동하며, 핀틀에서 발생하는 끝단 충격파가 약해진다. 핀틀 반경(tip radius)이 작아질수록 핀틀에서 발생하는 끝단 충격파가 하류로 이동하며, 크기는 약해진다. 핀틀 형상(contour)은 유동 박리 지점에 직접적인 영향을 미친다.

• Composites Research
• /
• v.25 no.3
• /
• pp.82-89
• /
• 2012

This paper investigated the composite materials application examples and trends in the future to the solid rocket motor cases. The motor case must be stiff and tolerate at the high pressures, and light weight. In accordance to these kind of requirements, the composite materials showed the adaptable efficiency, and glass fibers, aramid, carbon fibers are applied to orderly. The comparison of the motor case efficiencies of the D6AC steel alloy, aramid, carbon fibers results in the carbon fibers best. Also the capacity of the payload will be increased more than 20% by using the high strength ones.

• The Journal of the Acoustical Society of Korea
• /
• v.39 no.4
• /
• pp.371-377
• /
• 2020

Combustion instability occurred in the combustion test of solid rocket motor with large aspect ration Length/Diameter (L/D) and cylinder-slot grain. As a result of spectral analysis of the pressure perturbation, it was confirmed that the central axis longitudinal frequency was dominant, so that the length of the cylinder part was increased to eliminate the coincidence with acoustic node. In addition, acoustic modal analysis and flow analysis were performed to analyze the cause of instability by unsteady flow structure in solid rocket motors. It was confirmed that the combustion instability is reduced by quantitative comparison of the amplitude and frequencies of the pressure inside the combustion chamber using the grain shape before and after the design change. Finally, a combustion test was performed to verify that the combustion instability was resolved as in the flow analysis.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2006.05a
• /
• pp.393-397
• /
• 2006

In this study, combustion characteristics of solid propellants using sorbitol and potassium nitrate were found out. Burning rate was calculated with several combustion experiments, also specific impulse and characteristic exhaust velocity were compared with theoretical value. Thrust measured with thrust measurement system using plate spring. Mixture ratio of propellants was varied in experiments, also combustion characteristics of solid propellants which consulted experimental results was used micro solid rocket design having 1mm nozzle throat.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.17 no.9
• /
• pp.2280-2285
• /
• 1993

Many items, as internal pressure, thrust, temperature, strain, etc. are measured in Ground Firing Test (GFT) of rocket motors. But these items are influenced by various phenomena occurred during propellant combustion. In this study, natural frequencies of motor itself and system(motor+loadcell) on Stand were measured. Also motor responses were measured during burning and analyzed so that the vibration characteristics occurred during GFT and the causes and characteristics of vibration signal appearing on thrust curve were identified.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2008.05a
• /
• pp.213-216
• /
• 2008

U. S. and NATO allies have recently increased their emphasis on reducing the hazards of tactical munitions that contain energetic materials and actively started many investigations on Insensitive munitions(IM) of missile propulsion. All subcomponents of rocket motor should be properly designed and understood to increase IM properties. Insensitive propellant, motor case, ignitor and mitigation devices are important components of IM technologies of rocket motors.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.15 no.3
• /
• pp.31-39
• /
• 2011

The flowfield in a solid rocket motor was simulated at the wall-injection test model, which has a fin-slot grain and submerged nozzle, and visualized by a smoke-wire. The high speed CCD camera captured the visualized images around the nozzle inlet through the grain center port. The vortical tube structure and circumferential flow patterns at the nozzle throat were visualized. The radial momentum transfer caused by the shear-interactions of slot-outlet flow, fin-base flow and grain port flow from upstream worked as the source of these phenomena.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.11a
• /
• pp.213-216
• /
• 2010

A typical unsteady internal ballistic analysis model was proposed to take account of the erosive burning for a solid rocket motor. The variance of local velocity and pressure along grain surface are analyzed by using the continuity and momentum equation. The model introduced in this study showed good agreements with the results of previous internal ballistics program. It was investigated that the change of combustion pressure, gas velocity and regrestion rate along the grain axis.