• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.149-156
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• 2007

A three-dimensional inviscid flow solver has been developed based on unstructured meshes for the simulation of steady and unsteady flowfields around a generic fighter aircraft and for the investigation of the aerodynamic interference between the external stores and the tail surfaces. The flow solver is based on a vertex-centered finite-volume method and an implicit point Gauss-Seidel relaxation scheme. To validate the flow solver, calculations were made for a steady flow and the computed results were compared with experimental data. An unsteady time-accurate computation of the generic fighter aircraft with external stores at transonic flight conditions showed that the external stores cause undesirable vibration on the horizontal tail surface due to the mutual interference between their wake and the horizontal tail surface. It was shown that downward deflection of the trailing edge flap significantly reduces the undesirable interference effect.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.9
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• pp.823-831
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• 2011

According to the development of loading equipments, it is usual to change or replace the existing stores. It has been known that pylon-mounted under stores strongly affect aircraft dynamics characteristics due to the change of aerodynamics. To predict the aerodynamics and aero-elasticity is essentially requested with considering the configuration and shape of external stores during the development of aircraft and/or external stores. In this paper, computational fluid dynamics and computational structure dynamics interaction methodology are applied for prediction of aerodynamic characteristics for F-5 aircraft's horizontal tail with various shape of external stores. FLUENT and ABAQUS were used to calculate fluid and structural dynamics. Code-bridge was made base on the globally supported radial basis function to execute interpolation and mapping. As a result, even though the aeroelasticity of the horizontal tail slightly changes according to the shape of external store, the flutter was not occurred at the considered flight conditions in this study.

• Journal of Aerospace System Engineering
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• v.9 no.1
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• pp.28-34
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• 2015

Armed aircraft of a basic trainer class installs external stores under wing box by using pylon and performs an operation such as weapon delivery and jettison, and should be designed to withstand all kinds of loads applied to external stores. The static strength test of pylons and wing box was performed to assess the static strength of pylon and their support structures for substantiation. Based on the test, the structures were verified to fully satisfy a given design requirement. In this paper, methods of test load generation of wing box and pylon, evaluation of test result data and design result of test set-up were presented. Comparing the FEM analysis with the same test data can lead to good match and reasonable deviation between both. Finally, based on the test and the analysis, the static strength of test article was substantiated and the reliability and effectiveness of analysis math model were obtained.

• Journal of the Korea Institute of Military Science and Technology
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• v.26 no.1
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• pp.83-90
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• 2023

The external store fitted to the aircraft may affect the flight characteristics and flight safety of the aircraft, which requires the analyses and testing on it. The purpose of this study is to identify and analyze types of failures that can affect the flight safety of aircraft due to the installation of external stores, and to check the flight safety of aircraft through dropping tests of the external stores. After identifying the types of failures that could affect the flight safety of the aircraft, the criticality was calculated to analyze the effect on the flight safety of the aircraft. Four types of failures were selected: unintentional dropping, failure of dropping, unintentional main wing deployment, and release of tail wing restraint of the external store, which are considered to affect the flight safety of the aircraft due to the operation of the external store. As a result of the aircraft's flight safety analysis on the failure types, the criticality requirements were met. Based on this, after obtaining the airworthiness certification, the drop test was successfully performed to confirm the flight safety of the aircraft by mounting an external store on the aircraft. However, in addition to the four hazards carried out in this study, the real external stores of the military aircraft may have various factors affecting the flight safety of the aircraft, so further research will be needed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.3
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• pp.211-219
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• 2008

A three-dimensional inviscid flow solver has been developed based on unstructured meshes for the investigation of the effect of the external stores on the tail surfaces of a generic fighter aircraft. The numerical method is based on a vertex-centered finite-volume discretization and an implicit point Gauss-Seidel time integration. The calculations were made for a steady flow and the computed results were compared with experimental data to validate the flow solver. An unsteady time-accurate computation of the generic fighter aircraft with external stores at transonic flight conditions showed that the external stores cause unsteady loading on the horizontal tail surface due to the mutual interference between their wake and the horizontal tail surface. It was shown that downward deflection of the trailing edge flap significantly reduces the undesirable interference effect.

• Korean Institute of Interior Design Journal
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• v.25 no.4
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• pp.23-34
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• 2016

The purpose of this study was to investigate the influential factors of space marketing, and then to empirically analyze how they were reflected on the facade elements of sports stores. In order to achieve such a purpose, the research was firstly based on the perspective of space marketing to extract various features into 4 types of factors, namely sensuous factors, differentiated external appearance factors, image-associating factors and story-creating factors. Secondly, this study extracted the elements of facade design for sports stores including architectural elements, visual elements and display elements. Thirdly, it clarified the correlation of the influential factors of space marketing with the external space elements of sports stores. Fourthly, the qualitative analysis method was applied to analyze eight selected cases in Busan and eight selected cases in Fukuoka, Japan in order to explore the various different methods of expression of facade design. Lastly, the study found that the stores in Busan mostly take advantage of contrasting effects to deliver a strong visual impression to customers in the sensuous factors. Besides, the facade shapes in Busan were designed to be straight in order to enhance the main doors with its distinguished formative features to maximize the effective expression of the differentiated external factors, along with other expression methods of the image associating and story creating factors. This was done to associate with the brand identity in comparison with the stores in Fukuoka.

• Structural Engineering and Mechanics
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• v.8 no.2
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• pp.181-191
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• 1999

This paper presents an investigation of the mode localization and frequency loci veering phenomena in an aircraft with disordered external stores. Two theoretical analyses are carried out to study the occurring mechanism of the two phenomena: condensation technique in the subspace spanned by modes of interest and geometric mapping theory in the complex plane. Two simple criteria for predicting the occurrence of the mode localization and frequency loci veering are put forward. The prediction of the phenomena by our theoretically proposed criteria is in good agreement with that obtained through numerical calculations of characteristic solutions of the disordered system.

• Korean Journal of Human Ecology
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• v.23 no.1
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• pp.101-122
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• 2014

In this study, the Pine & Gilmore(1998) and Schmitt(1999, 2003), based on previous studies. Recent trends in large department stores and distribution outlets, discount stores and large retail centers, such as the consumer's experience is divided into internal and external fashion brand stores navigation study. Fashion Brand Stores are defined as the inside of the fashion brand store of the form that sells only the products of a fashion company's brand. Meanwhile, shopping center is defined as all the places at the inside and out of the shopping center excluding the inside of the fashion brand store. Likewise, definitions are clarified as such for use. As for the research method for this study, semi-structured focus group interviews were used since they could provide many more data compared to in-depth interviews. Accordingly, data was collected while carrying out free discussions while two to three subjects listened to each other's opinion regarding the key words raised by the interviewer and while thinking about their experience at the inside and outside of the fashion brand stores. As for the subjects, female consumers between the ages of 20 and 50 were targeted, and the interviews conducted with four, seven, four and three women in their 20s, 30s, 40s and 50s, were used, respectively. Likewise, there were a total of 18 subjects. Exploratory Study of Customer Experience area was classified into integration of significance and categorization. In particular, the contents were classified into elements of experience inside the fashion brand stores and fashion brand stores outsider experience in the shopping center elements and the elements of the common experience of fashion stores and shopping centers based on the results concerning the key contents identified in-depth from the customer aspect. The key experience elements at the inside of fashion brand stores were identified as VMD experience, emotional experience, and experience of the service provided by sales representatives. As for the key experience elements at the shopping center which is at the outside of the fashion brand store, they included service scape experience, cultural event experience, playful behavior experience. Meanwhile, elements of common experience included educational experience and exclusivity experience and human respect experience, which demonstrated some difference in terms of the contents.

• Journal of the Korea Institute of Military Science and Technology
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• v.10 no.4
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• pp.73-80
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• 2007

Modern aircraft are required to carry various external stores mounted at different locations on the wing. Sometimes the attachment of stores to an aircraft wing leads to flutter speed reduction, which is a very severe aeroelastic problem. In order to suppress structural vibration and expand the flutter boundary of the aircraft with stores, it is necessary to investigate the main problems and characteristics of them. In addition, active vibration control may be required because passive vibration isolators show limited capabilities for the various wing/store configuration. In this paper, therefore, the flutter stability to the various wing/store configurations was investigated and active vibration control of wing/store model was performed using a piezoelectric actuator.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.1
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• pp.74-80
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• 2013

In this paper, we have proposed a vapor cycle refrigeration system as a cooling system to provide cooling air to the aircraft external reconnaissance stores. In the proposed vapor cycle system, receiver which prevents refrigerant from subcooling was eliminated and thermal expansion valve was replaced with electronic expansion valve. The vapor cycle refrigeration system is aimed to provide cooling air to the reconnaissance stores which is added to the aircraft in the form of external store. The wide temperature range of ambient air from the flight conditions can decrease the cooling performance and can make the refrigeration system unstable in low ambient temperature. Performance characteristics of the vapor cycle refrigeration system has been experimented under air conditions which is derived from the flight envelope. From the experiments, the vapor cycle refrigeration system has been proved to provide enough cooling air to the reconnaissance equipment and to be stable under all the flight conditions.