• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1595-1600
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• 2007

It is necessary a simple helicopter design and performance analysis program for a stage of helicopter conceptual design. To meet that needs, we have developed a program which is simply used to estimate helicopter configuration and performance. The program developed by this study is composed of Requirement, Mission profile Analysis, Size, Aerodynamic, Trim, Propulsion, Weight, and Performance modules, and each modules carry out operations for a given flight condition. In this study, we validate this analysis program in 9,500 1bs and 22,000 1bs helicopters and estimate design configuration and performance of 16,000 1b helicopter. And We can use this program to optimization process for Helicopter MDO framework.

• 한국항공우주학회지
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• 제40권8호
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• pp.703-710
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• 2012

헬기개념설계단계에서는 많은 수의 반복계산과 Trade-Off Study가 필요하기 때문에 상대적으로 단순한 해석기법을 이용하는 것이 보통이다. 이때 해석코드에 사용되는 경험적 파라메터는 주로 사용자의 경험에 의지하는 경우가 많은데, 이러한 경험적요소가 개념설계결과의 신뢰도와 정확성에 큰 영향을 미치게 된다. 따라서, 이러한 헬기개념설계도구에 사용되는 경험적파라메터를 보다 정확하고 논리적으로 산출하기 위한 새로운 기법이 필수적이다. 본 연구에서는 요구에 따라 산출된 경험적파라메터를 검증할 뿐만 아니라, 오류가 있을 경우 재산출하는 기법을 제안하였다. 현재 운용중인 특정헬기의 성능 및 유상하중을 설계헬기의 성능 및 중량추정의 목표값으로 설정한 후 최대이륙중량을 기준으로 참조헬기를 선정하고 참조헬기의 경험적파라메터를 헬기개념설계도구에 대입하여 설계해본 결과 오차범위 ${\pm}5%$ 이내로 목표 값과 일치함을 보였다. 본 연구에서 정립한 경험적파라메터 결정 기법이 개념설계 단계에서 효율적으로 활용될 수 있음을 확인하였다.

• International Journal of Aeronautical and Space Sciences
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• 제18권1호
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• pp.154-164
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• 2017

This work conducts a validation study for the XH-59A helicopter using a rigid coaxial rotor system in order to establish the techniques of the conceptual design and performance analysis for the lift-offset compound rotorcraft. As a tool for conceptual design and performance analysis, NDARC (NASA Design and Analysis of Rotorcraft) is used for the present study. An assumed mission profile is considered for the conceptual design of the XH-59A. As a validation result of the design, the dimensions and weight of the XH-59A are appropriately designed when compared to the target values since the relative error is less than 0.5%. Then, performance analyses are conducted for the designed XH-59A model with and without auxiliary propulsion in hover and forward flight conditions. The present analyses show good validity since the prediction results compare well with both the flight test and previous analyses. Therefore, the techniques for the conceptual design and performance analysis of the lift-offset compound helicopter are overall considered to be appropriately established. In addition, this study investigates the influence of the lift-offset on the rotor effective lift-to-drag ratio of the XH-59A helicopter with auxiliary propulsion. As a result, the improvement of the rotor effective lift-to-drag ratio can be obtained by appropriately increasing the lift-offset in high-speed flight.

• Journal of Biosystems Engineering
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• 제33권2호
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• pp.94-100
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• 2008

Present chemical application method using a power sprayer has been labor intensive, costly and ineffective. Therefore, a small agricultural unmanned helicopter was suggested to replace the conventional spray system. In this study, conceptual design for developing the helicopter and a consequential prototype were reported. The overall conceptual design was initiated by deciding the type of agricultural helicopter, as the single rotor helicopter with a tail system. As the first step of the designing, an air-cooled, 2-stroke engine was selected and a prototype transmission was designed by determining the rotating speed of main rotor shaft. A 'pusher' type tail rotor system was adapted to balance the reaction torque and reduce the power use. The tail boom length was designed to avoid the rotating trajectory of the main rotor. The RF console consisted of the engine control, attitude control, and emergency control modules. Assembling the prototype concluded the mechanical development of the agricultural helicopter.

• 한국군사과학기술학회지
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• 제8권3호
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• pp.33-41
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• 2005

This paper describes the conceptual design of medium size helicopter rotor system. Based on assumed design requirements, trade-off study for rotor configuration has been conducted in terms of rotor tip speed, disk loading, blade area, solidity, etc for estimated primary mission gross weight. For the main rotor, four-blade and five-blade rotors are studied with the conventional tail rotor. The performance analysis for baseline configuration is conducted using a helicopter performance analysis program. The analysis shows design results satisfy the design requirements.

• International Journal of Aeronautical and Space Sciences
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• 제18권4호
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• pp.641-650
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• 2017

In order to include the design capability for a compound rotorcraft in a helicopter conceptual design and optimization framework, relevant further improvement was planned and conducted. Previously, a certain conceptual design optimization framework was developed by the present authors to design a modern rotorcraft with single main and tail rotor. The previously developed framework was further improved to expand its capability for a compound rotorcraft. Specifically, its power estimation algorithm was upgraded by using a comprehensive rotorcraft analysis program, CAMRAD II. The presently improved conceptual design and optimization framework was validated using data of the XH-59A aircraft.

• International Journal of Aeronautical and Space Sciences
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• 제6권1호
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• pp.89-96
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• 2005

Ducted fans have advantages in noise as well as operational safety aspects compared to conventional tail rotors and are used as an anti-torque system for various classes of helicopters. The final goal of this study is to develop a ducted fan anti-torque system which can replace conventional tail rotors of existing helicopters to achieve safety enhancement and low noise level. In this paper, a conceptual design process and the results are described. Initially, the design requirement and the design parameter characteristics are analysed, and then initial sizing and configuration design are performed. There are several configuration changes due to specific technical reasons in each case. Finally, the required power and the pitch link load are predicted as an initial estimation. The conceptual design technique for the ducted fan in this study can be easily applied to the design of other ducted fans such as the lift fan for unmanned aerial vehicle.

• 한국항공운항학회지
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• 제16권4호
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• pp.1-11
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• 2008

This research presents a study for the knowledge-based configuration design development of a RC (remote control) helicopter. Parametric design and knowledge based design concepts are introduced for rapid design changes and analyses using commercial CAD software, CATIA(R) Knowledgeware module. It is crucial for RC helicopter design because it enables rapid conceptual design through instant configuration changes. Positions and dimensions of RC helicopter parts were used as design parameters. As an example, positions of CG(center of gravity) points were traced and plotted as the configuration changes. Further research should be performed in areas of user interfaces and web-based multi-user environments instead of using Excel data sheets.

• 한국항공우주학회지
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• 제44권10호
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• pp.877-886
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• 2016

본 연구에서는 단일로터-꼬리로터 형상의 일반 헬리콥터에 대한 개념설계 및 성능해석 기법을 정립하고자 회전익 항공기 개념설계 및 성능해석 코드인 NDARC을 이용하여 UH-60A 헬리콥터에 대한 개념설계 및 성능해석을 수행하였다. 적절히 가정한 임무 형상을 이용하여 UH-60A 헬리콥터의 개념설계를 수행한 뒤 설계 목표 값과의 비교를 통하여 UH-60A 헬리콥터의 형상 및 중량을 적절히 설계할 수 있음을 확인하였다. 더불어, 본 연구로부터 설계된 UH-60A 헬리콥터 모델을 이용하여 다양한 비행 조건에서의 성능해석을 수행한 뒤, 본 연구의 해석 결과를 UH-60A의 성능 시험 및 선행 연구의 해석 결과와 비교하여 본 연구 결과의 타당성을 검증하였다. 그 결과, 단일로터-꼬리로터 형상의 일반 회전익 항공기의 개념설계 및 성능해석 기법을 적절히 정립하였음을 확인하였다.

• 한국군사과학기술학회지
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• 제10권1호
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• pp.22-32
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• 2007

This paper describes a study of a helicopter database for the sizing stage of a preliminary design process. The database includes specifications and performance parameters for more than 150 conventional single rotor helicopters currently in market. Design parameters, including configuration and weight parameters, have been analyzed and trend curve equations(regression equations) are derived using the regression analysis method. Finally, the applicability of this research result was verified whether the method is reliable for being adopted as a useful design tool in the early stage of a helicopter design process.