• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.220-223
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• 2007

Acoustic test of the payload fairing of Korea satellite launch vehicle was conducted to verify the performance of acoustic protection system installed inside the payload fairing. This paper briefly introduces the acoustic test procedures and its results. Overall 148 dB acoustic loads were exerted on the payload fairing structures which mated with the upper stage structure of the launch vehicle. In order to verify the increase of insertion loss by the acoustic protection system, two kinds of test were performed. One is conducted with acoustic protection system and the other without acoustic protection system. Internal acoustic loads as well as external ones were measured and the measured insertion losses were compared with the requirement. The results showed that the acoustic protection system increases the insertion loss by more than 6 dB above 125 Hz. They also indicated that some design modification of Helmholtz resonator array is required to increase the insertion loss at a cavity resonant frequency.

• Structural Engineering and Mechanics
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• 제13권3호
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• pp.345-353
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• 2002

Three noded plate and shell finite element and 3D beam element in conjunction with Lanczos method are used for studying the effect of boat tail angle on the free vibration characteristics of a typical payload fairing for three different cylinder diameters with height to diameter ratio 1.5. Configurations without boat tail structural member are also studied. One half of the one side fairing structure is considered for the analysis and symmetric boundary conditions are used.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.448-451
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• 2008

KARI is developing a satellite launch vehicle that is called KSLV(Korea Space Launch Vehicle)-I. During the flight, launch vehicles are exposed to aerodynamic heating conditions while flying at high Mach numbers in the atmosphere. KARI constructed Aerodynamic Thermal Simulation Facility to simulate aerodynamic heating on the ground. ATSF is a facility that can simulate given temperature profile using about 4,000 halogen heaters on fairing model. Aerodynamic heating profile is got from result of thermal analysis using MINIVER, Thermal Desktop, and SINDA/FLUINT. Aerodynamic heating test of fairing of KSLV-I was done using engineering model of payload fairing and Aerodynamic Thermal Simulation Facility. It was found that thermal analytic results show good agreement with aerodynamic heating test results within 6$^{\circ}$C at fairing inner surface. Also it was confirmed that maximum temperature of fairing nose-cone inner surface during flight is lower than allowable temperature limit.

• Advances in aircraft and spacecraft science
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• 제7권4호
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• pp.371-385
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• 2020

A forward-facing aerospike attached to a payload fairing of a satellite launch vehicle significantly alters its flowfield and decreases the aerodynamic drag in transonic and low supersonic speeds. The present payload fairing is an axisymmetric configuration and consists of a blunt-nosed body along with a conical section, payload shroud, boat tail and followed by a booster. The main purpose of the present numerical simulations is to evaluate flowfield and assess the performance of aerodynamic drag coefficient with and without aerospike attached to a payload fairing of a typical satellite launch vehicle in freestream Mach number range 0.8 ≤ M_∞ ≤ 3.0 and freestream Reynolds number range 33.35 × 10⁶/m ≤ Re_∞ ≤ 46.75 × 10⁶/m whichincludes the maximum aerodynamic drag and maximum dynamic conditions during ascent flight trajectory of the satellite launch vehicle. A numerical simulation has been carried out to solve time-dependent compressible turbulent axisymmetric Reynolds-averaged Navier-Stokes equations. The closure of the system of equations is achieved using the Baldwin-Lomax turbulence model. The aerodynamic drag reduction mechanism is analysed employing numerical results such as velocity vector plots, density and Mach contours in conjunction with the experimental flow visualization pictures. The variations of wall pressure coefficient over the payload fairing with and without aerospike are exhibiting different kind of flowfield characteristics in the transonic and low supersonic speeds. The numerically computed results are compared with schlieren pictures, oil flow patterns and measured wall pressure distributions and exhibit good agreement between them.

• 한국소음진동공학회논문집
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• 제21권12호
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• pp.1146-1151
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• 2011

Acoustic load from rocket propulsion system is main source of random vibration working on the payload. To protect payload from this acoustic load, additional APS(acoustic protection system) is generally applied. Noise reduction capacity of APS can be verified through acoustic test and vibro-acoustic coupled analysis. This paper compared the results of acoustic test and vibro-acoustic coupled analysis about KSLV-I payload fairing with APS.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 추계학술대회 논문집
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• pp.196-201
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• 2011

Acoustic load from rocket propulsion system is main source of random vibration working on the payload. To protect payload from this acoustic load, additional APS(acoustic protection system) is generally applied. Noise reduction capacity of APS can be verified through acoustic test and vibro-acoustic coupled analysis. This paper compared the results of acoustic test and vibro-acoustic coupled analysis about KSLV-I payload fairing with APS.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2006년도 PARALLEL CFD 2006
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• pp.90-93
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• 2006

• 한국항공우주학회지
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• 제41권11호
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• pp.900-907
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• 2013

페이로드 페어링은 위성과 부품들을 외부환경으로부터 보호하며, 위성분리 전에 페이로드 페어링은 분리된다. 페이로드 페어링은 굽힘 강성과 무게에 비해 강도 비율이 우수한 복합재 샌드위치 재료로 제작 되었다. 페이로드 페어링은 비행 중에 압축, 굽힘 그리고 전단하중을 받게 된다. 본 연구에서는 PLF와 연결구조물의 강도를 확인하기 위하여 액추에이터와 치구를 사용하여 PLF 구조시험을 수행하였다. 구조시험의 목적은 분리 스프링의 힘이 PLF에 가해진 상태에서 조합하중이 PLF에 작용할 때 PLF의 건전성을 확인하는 것이다. 구조시험 결과에서는 분리 스프링 하중과 조합하중에 의한 PLF의 구조 건전성을 확인하였다.

• 한국항공우주학회지
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• 제35권12호
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• pp.1129-1134
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• 2007

페이로드 페어링은 외부환경으로부터 위성 및 전자 탑재물들을 보호한다. 그리고 위성 분리 전에 페이로드 페어링은 투하 된다. 페어링 분리를 위하여 전단볼트로 체결된 체결프레임이 페이로드 페어링에 조립되어 있다. 전단볼트의 역할은 전체 구조하중을 견디며, 화약폭발력에 의해 절단이 된다. 그리고 전단볼트가 절단된 후 전단볼트로 연결되었던 체결 프레임은 분리된다. 본 논문에서는 전단볼트 설계에 대한 구조시험과 해석을 수행하였다. 구조시험은 체결 프레임을 포함한 하드웨어에 압축, 굽힘, 전단하중을 부가하였다. 시험결과 전단볼트는 비행하중 지지를 위한 구조강도와 화약폭발에 의해 절단되는데 요구되는 낮은 강도 조건을 만족하였다.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.547-550
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• 2006

An analysis method is developed for the prediction of venting in multiple compartments which are connected in series or parallel through multiple ports. The existing method by the authors is modified to remove the limitation in number of ports and compartments, and the more general polytropic relation or solution of the additional energy equation replaces the previous isentropic relation allowing the prediction of pressure rise in addition to pressure drop. The accuracy of the method is verified by comparison with the results by NASA Flap code for the problem of pressure drop in a payload in the Space Shuttle cargo bay. It is expected that this method will be a useful tool in prediction of the pressure variation in a payload or payload capsule without mentioning the payload fairing itself.