• Title/Summary/Keyword: Wings

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Study on the stall characteristics improvement and compliance verification of the G.A. airplane (소형비행기 실속특성 향상 및 적합성검증 방안 연구)

  • Choi, Joowon;Kim, Jinsoo
    • Journal of Aerospace System Engineering
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    • v.8 no.3
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    • pp.47-54
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    • 2014
  • This is a research on the method of how to improve stall characteristics for the small general aviation airplanes to meet the FAR part 23 requirements. This research is based on the experience of certification flight tests of KC-100 airplane for Korea type certification. KAS/FAR Part 23.201/203 are the stall characteristics requirements. 23.201 requires to show the stable stalling tendency of the wings level stall and 23.203 requires to show the stable stalling tendency of stall characteristics during turning flight. In this paper, the stall characteristics requirements, improvement methods and flight test experience of KC-100 airplane for type certification.

A Study on Effect of Flow Characteristics for Turbine Impeller Shape (Turbine Impeller 형상이 유동특성에 미치는 영향에 관한 연구)

  • Jeon, Eon-Chan;Youn, Gi-Ho;Kang, Chang-Hun
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.13 no.4
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    • pp.36-43
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    • 2014
  • Recently, research has been conducted to develop the ORC (organic Rankine cycle), to recover waste heat from facilities such as industrial plants ultimately to create mechanical or electrical energy. The ORC system consists of a heat exchange, a condenser, a pump and a boiler. In this paper, 84 flow analyses were conducted with 21 cases and three variables, i.e., a number of large wings, a number of small wings, and RPMs. R245fa was used as a refrigerant. The flow cavitation phenomenon was investigated through a flow analysis, and a flow stream analysis was conducted.

The Effect of Folding Wing on Aerodynamics and Power Consumption of a Flapping Wing

  • Lee, Seunghee;Han, Cheolheui
    • International Journal of Aerospace System Engineering
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    • v.3 no.2
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    • pp.26-30
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    • 2016
  • Experimental study on the unsteady aerodynamics analysis and power consumption of a folding wing is accomplished using a wind tunnel testing. A folding wing model is fabricated and actuated using servo motors. The flapping wing consists of an inboard main wing and an outboard folding wing. The aerodynamic forces and consumed powers of the flapping wing are measured by changing the flapping and folding wings inside a low-speed wind tunnel. In order to calculate the aerodynamic forces, the measured forces are modified using static test data. It was found that the effect of the folding wing on the flapping wing's total lift is small but the effect of the folding wing on the total thrust is larger than the main wing. The folding motion requires the extra use of the servo motor. Thus, the amount of the energy consumption increases when both the wings are actuated together. As the flight speed increases, the power consumption of the folding wing decreases which results in energy saving.

Angel Wing in a Young Captive-Reared Spot-Billed Duck (Anas poecilorhyncha) (포획되어 사육된 어린 흰뺨검둥오리에서 발생한 엔젤윙의 진단 및 치료 증례)

  • Jeong, Yikyeong;Lee, Sung Kyung;Park, Seongjun
    • Journal of Veterinary Clinics
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    • v.36 no.1
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    • pp.85-87
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    • 2019
  • Eight-week-old Spot-billed duck were presented with visible drooping of both of wings. On physical examination, the Spot-billed ducks revealed valgus deformity of the carpal joint resulting in the primary flight feathers protruding dorsally. The bird was in good body condition and there was no loss of motion in any of the joints in the wings. The bird was fed chicken pellet with 18.5% of protein level and reared in a cage. Based on the clinical presentation and physical examination 'angel wing' was diagnosed. Wing bandage and nutritional change to lower-protein diet with fresh vegetables were applied simultaneously. And duck was transferred to wider outside pen with small pond. Four-week afterward clinical signs of angel wing were improved.

Two New Records of Scopula (Lepidoptera: Geometridae) from Korea

  • Choi, Sei-Woong;Shin, Yoo-Hang;Kim, Sung-Soo
    • Animal Systematics, Evolution and Diversity
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    • v.37 no.1
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    • pp.81-83
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    • 2021
  • Two species of Scopula, S. asthena Inoue, 1943 and S. tenuisocius Inoue, 1942, were newly recorded from Korea. Scopula asthena can be distinguished by the bipectinate male antennae and whitish wings with four blackish dots on each wing. This species is similar to S. superior (Butler, 1878) but differs in the large blackish discal dots on both wings. Scopula tenuisocius can be distinguished by its whitish forewing with light grayish, dentate antemedial line, short-line shaped discal dot and line light grayish, weakly rounded, dentate postmedial line, and whitish hindwing with a blackish discal dot and light grayish, undulating medial lines. Scopula tenuisocius is similar to S. floslactata (Haworth, 1809) but the species can be distinguished by the thinner and blackish subterminal line of the forewing that appears minutely dentate along the line. To date, 41 species of the genus Scopula are known in Korea.

Aerodynamic shape optimization of a high-rise rectangular building with wings

  • Paul, Rajdip;Dalui, Sujit Kumar
    • Wind and Structures
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    • v.34 no.3
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    • pp.259-274
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    • 2022
  • The present paper is focused on analyzing a set of Computational Fluid Dynamics (CFD) simulation data on reducing orthogonal peak base moment coefficients on a high-rise rectangular building with wings. The study adopts an aerodynamic optimization procedure (AOP) composed of CFD, artificial neural network (ANN), and genetic algorithm (G.A.). A parametric study is primarily accomplished by altering the wing positions with 3D transient CFD analysis using k - ε turbulence models. The CFD technique is validated by taking up a wind tunnel test. The required design parameters are obtained at each design point and used for training ANN. The trained ANN models are used as surrogates to conduct optimization studies using G.A. Two single-objective optimizations are performed to minimize the peak base moment coefficients in the individual directions. An additional multiobjective optimization is implemented with the motivation of diminishing the two orthogonal peak base moments concurrently. Pareto-optimal solutions specifying the preferred building shapes are offered.