• International Journal of Aeronautical and Space Sciences
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• 제17권4호
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• pp.551-564
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• 2016

High-speed flight vehicles (HSFVs) such as space launch vehicles and missiles undergo severe dynamic loads which are generated during the launch and in in-flight environments. A typical vehicle is composed of thin plate skin structures with high-performance electronic units sensitive to such vibratory loads. Such lightweight structures are then exposed to external dynamic loads which consist of random vibration, shock, and acoustic loads created under the operating environment. Three types of dynamic loads (acoustic loads, rocket motor self-induced excitation loads and aerodynamic fluctuating pressure loads) are considered as major components in this study. The estimation results are compared to the design specification (MIL-STD-810) to check the appropriateness. The objective of this paper is to study an estimation methodology which helps to establish design specification for the dynamic loads acting on both vehicle and electronic units at arbitrary locations inside the vehicle.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.1000-1005
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• 2003

The shock separation test simulates the environmental effects of the spacecraft separation from launch vehicle. The shock separation test for a structural model of KOMPSAT-Ⅱ(Korea Multi-Purpose SATellite Ⅱ) was performed in SITC(Satellite Integration ＆ Test Center) launch environmental test hall at KARI(Korea Aerospace Research Institute) to verify the shock test requirement of the spacecraft, to predict the induced acceleration responses on the primary structures and payloads by the explosion of pyre-lock and to perform mechanical fit check. The spacecraft with S/A was mated vertically to LV(Launch Vehicle) adapter simulator via a clamp band, then hoisted and suspended above a foam test bed by four isolation springs secured to the spacecraft hoist fittings to isolate the payload platform shock wave from the sling elements. For separation process, real pyre-devices were used and the time response signals from 60 accelerometers installed on the interested points was acquired and recorded. The SRS responses for each response channels were calculated and the achieved SRS's on the separation plane was reviewed and evaluated in comparison to the ICD(Interface Control Document) value.

• Journal of Astronomy and Space Sciences
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• 제16권1호
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• pp.79-88
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• 1999

인공위성은 로켓을 이용하여 궤도에 진입하며 발사과정 중 진동, 가속, 충격, 소음 등과 같은 극심한 발사환경을 경험하므로, 이와 같은 발사조건에 견딜 수 있도록 설계/제작 되어야 한다. 본 논문에서는 우리별 3호 비행모델의 구조체에 대해 소개하고, 발사과정에서 겪게 되는 환경을 지상에서 시험한 발사환경시험의 과정과 결과를 소개하고자 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.614-615
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• 2008

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.224-227
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• 2007

This paper introduces the results of acoustic loads test conducted on the upper stage assembly of KSLV-I, which is the first Korea space launch vehicle. A launch vehicle and its payloads are subjected to severe acoustic pressure loading when they lift off and ascent during the transonic periods. Acoustic loadings are spreaded out broad frequncy-spectrum up to 10,000Hz. Acoustic loads are a primary source of structural random vibration of the upper stage and payloads. Therefore, in order to verify the structural integrity of the upper stage assembly of KSLV-I and the survivability of its components under severe random vibration environment, acoustic loads test is conducted in the high intensity acoustic chamber with 142dB (overall SPL). The results show the structural design and component random vibration specifications well meet with the environmental requirements.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 춘계학술대회논문집
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• pp.185-188
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• 2008

This paper introduces the Bootstrap method for statistical analysis of noise and vibration spectrum in aeronautic and space fields. Generally, all components of a launch vehicle and its payloads are subjected to high intensive noise and vibration environment during the lift-off phase and the ascent phase through Mach =1 and Max Q. In order to verify their survivabilities against these severe vibroacoustic environments during qualification tests and acceptance tests, it is most important to estimate the proper upper limits of the environmental condition. Although NASA has typically utilized the Normal Tolerance Limit method in deriving these levels, the reference[1] says that the Bootstrap can be also an alternative method to estimate the maximum expected environments. In this paper, a general procedure of the Bootstrap method is summarized, and it is applied to analyze acceleration power spectral density functions, which were measured during acoustic test on the upper stage of KSLV-I.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.756-762
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• 2011

화염유도로 냉각시스템은 발사체 엔진의 점화 시 발생하는 충격파를 감쇠하는 중요한 역할을 수행한다. 또한 이 시스템은 발사체의 구조와 페이로드를 손상시킬 수 있는 커다란 진동을 감소시키기도 한다. 나로우주센터의 발사대에 설치된 화염유도로 냉각시스템은 발사체 엔진의 화염에 직접 물을 분사시키도록 구축되었으며, 나로호의 비행시험 결과는 화염유도로를 냉각하는 관점에서 이 방법이 기능상 우수함을 보여 주었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.234-237
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• 2007

To protect a satellite and electronic equipment from the acoustic load generated by rocket propulsion system, many launch vehicle use acoustic blanket. Acoustic load is main source of random vibration working on the payload. Most high frequency region of the acoustic loads is reduced by payload fairing skins and acoustic blanket, but low frequency region is not. In order to reduce acoustic load of low frequency region, we designed array resonator panel which was made of composite materials. Insertion loss capacity of the payload fairing with acoustic blanket was verified from PLF acoustic test in the acoustic chamber.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.165-169
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• 2000

High level vibrationional environments induced while launching of spacecraft can damage sensitive equipment or payloads, unless the equipment is properly designed. This is a critical issue for KOMPSAT-2 which will carry a high resolution electro-optic camera and a sophisticated attitude and orbit control system. Thus careful consideration on the launch environment is required in the design stage of spacecraft. This requires generation of vibration specification for each component. This paper describes the generation process of vibrational specification for KOMPAT-2, which is designed and tested by Korean engineers.

• 소음진동
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• 제10권6호
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• pp.971-976
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• 2000

High level random vibration environments induced while launching of spacecraft can damage sensitive electronic equipment, unless the equipment is properly packaged. Thus careful consideration on the launch environment, especially for high level random vibration, is required in the design stage of electronic equipment of spacecraft. This paper describes the development process of Solar Array Regulator for KOMPAT-2, which is designed and tested by Korean engineers. Both analytical and experimental techniques are introduced in this paper.