• Journal of the Korean Society of Propulsion Engineers
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• v.16 no.3
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• pp.41-48
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• 2012

A study to determine the optimal jet conditions for maximizing altitude of the sounding rocket is conducted. The behavior of a simplified one-dimensional momentum equation including aerodynamic drag is investigated. The case where an analytic solution exists and the case where the mass flow rate is constant are calculated. The solutions are compared with numerical solutions. It is shown that there are the optimal jet conditions for maximizing altitude of a sounding rocket and the optimal condition is a function of the rocket mass ratio.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.1
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• pp.26-34
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• 2013

An analytic approach to determine the optimal conditions for maximizing altitude of a sounding rocket is suggested. The behavior of the one-dimensional momentum equation including thrust, gravitational force and aerodynamic drag force is investigated. For the case where an analytic solution exists, a characteristic equation for determining optimal condition for maximizing altitude at the burn-out state and that for maximizing altitude at the stationary state are developed and verified with numerical experiments.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.144-149
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• 2011

A study to determine the optimal jet conditions for maximizing altitude of the sounding rocket is conducted. The behavior of a simplified linear momentum equation including aerodynamic drag is investigated. The analytic solutions are obtained and compared with numerical solutions. It is shown that there are the optimal jet conditions for maximizing altitude of a sounding rocket according to the rocket mass ratio.

• Bulletin of the Korean Space Science Society
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• 2009.10a
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• pp.25.1-25.1
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• 2009

적외선 우주배경복사 관측실험 (Cosmic Infrared Background ExpeRiment, CIBER) II는 2009년 2월 25일 화이트샌드 미사일 기지에서 NASA 사운딩 로켓에 탑재, 발사된 CIBER I의 후속 프로젝트이다. 독립적인 Imager 2 대와 Spectrometer 2 대로 구성된 CIBER I과 달리 CIBER II는 하나의 주경과 부경으로 구성된 광학계를 4 대의 Imager가 beam splitter를 이용하여 관측하게 구성되어 있다. CIBER II는 NASA에서 공식적으로 승인되었으며, 한국천문연구원과 한국기초과학지원연구원이 미국 NASA/JPL, Caltech 및 일본 ISAS와 국제 공동으로 개발할 계획이다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.97-100
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• 2008

A hybrid sounding rocket carrying about 10kg payload reaching up to 15km altitude has been designed. The commercial seamless aluminium tube and liquid ${N_2}O$ without pressurization devices were chosen as rocket motor case and oxidizer supply system respectively. A hybrid rocket engine performing required propulsion impulse is designed with time dependent internal ballistic scheme. Engine performance, aerodynamic characteristics, and trajectory were predicted by a integral technique of internal ballistics and external ballistics. The design results were evaluated by comparison with previous experimental data, technical reports, and literatures.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.101.2-101.2
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• 2014

적외선 파장 대역에서 관측되는 우주배경복사의 요동은 초기 우주가 재이온화되는 시기에 존재하였던 우주 최초의 별 또는 은하에서 기원한다고 믿어진다. 적외선우주배경복사 관측을 위해서는 배경의 잡음이 되는 별, 은하, 황도광등을 제거하고 희미한 배경을 검출해야 하므로 광시야, 고감도로 광학에서 근적외선까지 다파장으로 관측하는 기능이 필요하다. CIBER2는 이러한 적외선우주배경복사 관측을 위해 개발되고 있는 NASA 사운딩로켓 탑재용 적외선카메라 시스템이다. 2009년부터 2013년까지 4차례에 걸쳐 성공적으로 발사된 CIBER를 업그레이드한 관측기기로써 한국 KASI, 미국 Caltech, 일본 ISAS가 공동으로 개발하고 있다. CIBER2는 28.5cm의 주경에 광분배기를 사용하여 3대의 카메라가 장착되는 형상을 이루고 있으며 각 카메라에는 $2K{\times}2K$ H2RG 검출기 위에 2개의 밴드 필터를 부착하여 0.6 - 2.1 um의 파장 대역을 6개의 구간으로 나누어 관측한다. 각 밴드의 시야각은 $1.1{\times}2.2$도이다. CIBER2는 현재 최종 설계를 마치고 각 서브시스템 별 제작 단계에 있으며, 조립 및 시험을 거쳐 2015년에 미국 화이트샌드 미사일기지에서 발사될 예정이다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.05a
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• pp.77-81
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• 2008

The local regression rate behavior of solid fuel in swirl injection hybrid rocket were studied. In generally, axial injection regression rate was tending to be decrease with axial distance, beyond which increased with increasing axial distance from the leading edge. On the other hand, swirl injection regression rate was high at the leading edge of the fuel and comparatively uniform regression rate at the downstream. Overall regression rate of swirl injection was increased about 54% for the overall regression rate of axial injection. Through this study, it was found that using swirl injector was useful in applying to the small sounding rocket.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.370-373
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• 2007

In this study, a hybrid rocket motor with separable and detachable oxidizer tank from combustion chamber is developed. Initially, the measured thrust of the motor showed about 30% of the design thrust since the oxidizer supply was not enough. In order to solve this problem, application is made to expand the orifice diameter of oxidizer injector empirically, so that the mass flow rate of oxidizer was improved. The improved performance was about 60% of design thrust, 18kgf, and thrust-to-weight ratio was reasonable, compared with other sounding rockets.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.503-506
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• 2009

In this study, we presented the results of static firing tests on the PE/LN2O hybrid rocket motor, which has a thrust of 650 kgf level. Through the early tests, we found that the combustion chamber pressure and the thrust were lower than design values because an actual oxidizer flow rate was less than that expected. In order to complement this result, the methods of decrease of nozzle throat and the increase of oxidizer mass flow rate were conducted in the next experiment, and we studied the combustion phenomena with the experimental results. Also we compared and analyzed a difference of combustion characteristics on scale effect. It show that a sub-scale motor regression rate was a little less than that of a lab-scale motor with the same oxidizer mass flux. Results of this study might be used as a basic data for development of hybrid sounding rocket.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.1
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• pp.64.1-64.1
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• 2012

Cosmic Infrared Background Experiment (CIBER)는 적외선 카메라 및 분광기를 NASA Sounding Rocket에 탑재, 발사하여 적외선우주배경복사를 관측하는 과제이다. CIBER1은 2006년 NASA의 공식 과제로 승인되어, 미국의 Caltech, 한국의 KASI, 일본의 ISAS/JAXA가 국제협력으로 진행되었으며, 2009년 2월 25일, 2010년 7월 10일, 그리고 2012년 2월 25일에 미국 화이트샌드 미사일 기지에서 NASA 사운딩 로켓에 의해 성공적으로 발사되어 우주관측에 성공하였다. CIBER2는 CIBER1 보다 약 10 배 이상의 성능을 가지는 적외선카메라로써 한국의 KASI는 CIBER2 개발에서 광학계 및 광기계부 개발, 전자부 개발에 참여하고 있다. CIBER2는 2012년에 개발을 시작하여 2013년과 2014년에 각각 발사될 예정이다.