• 제목/요약/키워드: Airplane

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A Study on the Estimations of Maximum Lift Coefficients of a Light Airplane (경비행기의 최대양력계수 추정에 대한 연구)

  • Lee, Jung-Hoon;Yoo, Si-Yoong
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.762-767
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    • 2008
  • Estimated values for maximum lift coefficients of a light airplane, ChanGong-91, derived from an analytical method using a test database, a computational fluid dynamic method, a wind tunnel test, and a flight test are compared. The DATCOM method and VSAERO code are applied as the analytical method and the computational fluid dynamic method, respectively, in order to estimate the maximum lift coefficients of a light airplane. The wind tunnel test is conducted using a 1/14.5 scaled model installed in a closed circuit type wind tunnel. For the flight test approach, the wings-level power-off stall tests are performed to obtain the maximum lift coefficients. As a point of reference for the flight test results of the maximum lift coefficients, the differences of both estimates derived from the DATCOM method and the wind tunnel test data are smaller than those derived from VSAERO.

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Thermo-elastic Frictional Contact Analysis of Airplane Brakes (항공기 제동장치의 열탄성 마찰 접촉 해석)

  • Lee, Chang-Won;Choi, Yong-Gie;Kwak, Byung-Man
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.889-894
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    • 2001
  • A three dimensional transient thermo-elastic frictional contact analysis of airplane brakes is performed. The velocity history of the airplane during braking is calculated from energy conservation law. ABAQUS code is used in the analysis, and user subroutines supported in the ABAQUS are coded to calculate the frictional heat generation between pads and linings attached to back/pressure plate and rotor, respectively. Numerical results are compared with experimental ones.

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Flow Analysis due to the Angle of the Front Wing on an Airplane (비행기에서의 앞날개의 각도에 따른 유동해석)

  • Han, Moonsik;Cho, Jaeung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.12
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    • pp.22-27
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    • 2019
  • In this study, the flow rate and air resistance pressure were analyzed on models a, b, and c due to the front wing angle of the airplanes. Models a, b, and c have front wing angles of 120°, 100°, and 160°, respectively. The results of the flow analyses showed that the flow rate and air resistance pressure of model c were observed to be higher than models a and b. The airplane model with a larger angle to the front wing is thought to be the best model for flight. This result can be applied to development of the best in-flight airplane.

Geometry Realization of an Airplane and Numerical Flow Visualization (역설계에 의한 비행기의 형상 구현과 수치계산에 의한 유동 가시화)

  • Kim, Yang-Kyun;Kim, Sung-Cho;Kim, Jeong-Soo;Choi, Jong-Wook;Park, Jeong
    • Journal of the Korean Society of Visualization
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    • v.5 no.2
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    • pp.20-25
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    • 2007
  • The geometry of a commercial passenger airplane is realized based on a Boeing 747-400 model through the photographic scanning and reverse engineering. The each element consisting of the plane such as fuselage, wing, vertical fin, stabilizer and engines, is individually generated and then the whole body is assembled by the photomodeler. The maximum error in the realized airplane is about 1.4% comparing with the real one. The three-dimensional inviscid steady compressible governing equations are solved in the unstructured tetrahedron grid system, and in a finite volume method using STAR-CD when the airplane flies at the cruise condition. The pressure distribution on the surface and the wing-tip vortices are visualized, and in addition to the aerodynamics coefficients, lift and drag are estimated.

A Study on the Effect Influencing on the Performance of Air Plane by the Air Flow due to Landing Gear Configuration (랜딩기어 형상에 따른 공기 유동으로 인한 항공기 성능에 미치는 영향에 관한 연구)

  • Han, Moonsik;Cho, Jaeung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.16 no.6
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    • pp.35-40
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    • 2017
  • The aerodynamic performance of airplane is different according to the configuration of landing gear. As the drag becomes different according to this configuration, the flow stream of air must be smooth at taking off and landing. In this study, the configuration of landing gear was designed each in order to enhance the energy efficiency of airplane. Five models were compared in total at analysis. The magnitudes of drag and pressure became different and the air pressure of wake were changed due to the configuration. So, the air pressure due to the flow velocity and the air resistance happening at the rear can be estimated according to the configuration of landing gear. It is thought to improve the performance of airplane through the result of this study.

Airfoil Design for Martian Airplane Considering Using Global Optimization Methodology

  • Kanazaki, Masahiro;Utsuki, Motohiro;Sato, Takaya;Matsushima, Kisa
    • International Journal of Aerospace System Engineering
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    • v.2 no.2
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    • pp.10-14
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    • 2015
  • To design airfoils for novel airplanes, new knowledge of aerodynamics is required. In this study, modified Parametric SECtion (PARSEC) which is a airfoil representation is applied to airfoil design using a multi-objective genetic algorithm to obtain an optimal airfoil for consideration in the development of a Martian airplane. In this study, an airfoil that can obtain a sufficient lift and glide ratio under lower thrust is considered. The objective functions are to maximize maximum lift-to-drag ratio and to maximize the trailing edge thickness. In this way, information on the low Reynolds number airfoil could be extracted efficiently. The optimization results suggest that the airfoil with a sharper thickness at the leading edge and higher camber at the trailing edge is more suitable for a Martian airplane. In addition, several solutions which has thicker trailing edge thickness were found.

Design and Implementation of the passenger board bridge controller based middleware (미들웨어 기반의 탑승교 설계와 구현)

  • Kim, W.Y.;Hong, J.H.;Jung, J.H.;Song, G.Y.;Song, W.J.;Jung, Y.H.;Kim, H.J.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05a
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    • pp.133-136
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    • 2002
  • In maned airport, crews may have risks as they manage passenger control system in IPMS in damage situations such as fire in a airport. So the application of unmanned autonomous system can reduce the number of boarding crews and attribute to safe airplane transportation. PBBC model can be used to obtain control strategy, and airplane and enhance operators' skill by simulating the airport. The paper suggests an intelligent system of the pbbc control using microprocessor in integrated platform management system which can take measures against passenger situation of a airplane excluding unnecessary warnings with undamaged situations. The system here detected the passenger more accurately and adopted more appriate measures according to airplane status compared with conventional systems.

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Prediction of Battery Performance of Electric Propulsion Lightweight Airplane for Flight Profiles (비행프로파일에 대한 전기추진 경량비행기의 배터리 성능 예측)

  • Kim, Hyun-Gi;Kim, Sungchan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.5
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    • pp.15-21
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    • 2021
  • Electrically powered airplanes can reduce CO2 emissions from fossil fuel use and reduce airplane costs in the long run through efficient energy use. For this reason, advanced aviation countries such as the United States and the European Union are leading the development of innovative technologies to implement the full-electric airplane in the future. Currently, the research and development to convert existing two-seater engine airplanes to electric-powered airplanes are underway domestically. The airplane converted to electric propulsion is the KLA-100, which aims to carry out a 30-minute flight test with a battery pack installed using the engine mounting space and copilot space. The lithium-ion battery installed on the airplane converted to electric propulsion was designed with a specific power of 150Wh/kg, weight of 200kg, and a C-rate 3~4. This study confirmed the possibility of a 30-minute flight with a designed battery pack before conducting a flight test of a modified electrically propelled airplane. The battery performance was verified by dividing the 30-minute flight profile into start/run stage, take-off stage, climbing stage, cruise stage, descending stage, and landing/run stage. The final target of the 30-minute flight was evaluated by calculating the battery capacity required for each stage. Furthermore, the flight performance of the electrically propelled airplane was determined by calculating the flight availability time and navigation distance according to the flight speed.

NUMERICAL AERODYNAMIC ANALYSIS OF A TRANSONIC COMMERCIAL AIRPLANE ACCORDING TO THE ANGLE OF ATTACK AND MACH NUMBER (천음속 여객기의 받음각과 마하수에 따른 공력 해석)

  • Kim, Y.K.;Kim, S.C.;Choi, J.W.;Kim, J.S.
    • Journal of computational fluids engineering
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    • v.13 no.4
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    • pp.66-71
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    • 2008
  • This research computes the viscous flow field and aerodynamics around the model of a commercial passenger airplane, Boeing 747-400, which cruises in transonic speed. The configuration was realized through the reverse engineering based on the photo scanning measurement. In results, the pressure coefficients at the several wing section on the wing surface of the airplane was described and discussed to obtain the physical meaning. The lift coefficient increased almost linearly up to $17^{\circ}$. Here the maximum lift occurred at $18^{\circ}$ according to the angle of attack. And the minimum drag is expected at $-2^{\circ}$. The maximum lift coefficient occurred at the Mach number 0.89, and the drag coefficient rapidly increased after the Mach number of 0.92. Also shear-stress transport model predicts slightly lower aerodynamic coefficients than other models and Chen's model shows the highest aerodynamic values. The aerodynamic performance of the airplane elements was presented.

How airplanes fly at power-off and full-power on rectilinear trajectories

  • Labonte, Gilles
    • Advances in aircraft and spacecraft science
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    • v.7 no.1
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    • pp.53-78
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    • 2020
  • Automatic trajectory planning is an important task that will have to be performed by truly autonomous vehicles. The main method proposed, for unmanned airplanes to do this, consists in concatenating elementary segments of trajectories such as rectilinear, circular and helical segments. It is argued here that because these cannot be expected to all be flyable at a same constant speed, it is necessary to consider segments on which the airplane accelerates or decelerates. In order to preserve the planning advantages that result from having the speed constant, it is proposed to do all speed changes at maximum deceleration or acceleration, so that they are as brief as possible. The constraints on the load factor, the lift and the power required for the motion are derived. The equation of motion for such accelerated motions is solved numerically. New results are obtained concerning the value of the angle and the speed for which the longest distance and the longest duration glides happen, and then for which the steepest, the fastest and the most fuel economical climbs happen. The values obtained differ from those found in most airplane dynamics textbooks. Example of tables are produced that show how general speed changes can be effected efficiently; showing the time required for the changes, the horizontal distance traveled and the amount of fuel required. The results obtained apply to all internal combustion engine-propeller driven airplanes.