• International Journal of Aeronautical and Space Sciences
• /
• 제18권4호
• /
• pp.651-661
• /
• 2017

A truss-braced wing (TBW) aircraft has recently received increasing attention due to higher aerodynamic efficiency compared to conventional cantilever wing aircraft. For conceptual TBW aircraft design, we developed a propulsion-and-airframe integrated design environment by replacing a semi-empirical turbofan engine model with a thermodynamic cycle-based one built upon the numerical propulsion system simulation (NPSS). The constructed NPSS model benefitted TBW aircraft design study, as it could handle engine installation effects influencing engine fuel efficiency. The NPSS model also contributed to broadening TBW aircraft design space, for it provided turbofan engine design variables involving a technology factor reflecting progress in propulsion technology. To effectively consolidate the NPSS propulsion model with the TBW airframe model, we devised a rapid, approximate substitute of the NPSS model by reduced-order modeling (ROM) to resolve difficulties in model integration. In addition, we formed an artificial neural network (ANN) that associates engine component attributes evaluated by object-oriented weight analysis of turbine engine (WATE++) with engine design variables to determine engine weight and size, both of which bring together the propulsion and airframe system models. Through propulsion-andairframe design space exploration, we optimized TBW aircraft design for fuel saving and revealed that a simple engine model neglecting engine installation effects may overestimate TBW aircraft performance.

• 한국항공운항학회지
• /
• 제25권1호
• /
• pp.35-39
• /
• 2017

The engine is the most significant and essential part of the aircraft. As a result, systematical handling in the aircraft development stage is required from engine design to implementation to the full-scale airframe. This survey demonstrates the procedures demanded by the KAS 23 Civil Aircraft to acquire the engine Type Certification and the flight test procedures for ensuring the operational stability. Surveys were conducted on domestic and international aircraft engine certifications, technical regulations and documentations related to the Means of Compliance for flight test development stage. In addition, organized reference items that should be considered for the certification of engine flight test procedures were reviewed based on the KC-100.

• 한국기계가공학회지
• /
• 제17권3호
• /
• pp.65-70
• /
• 2018

M152, used for aircraft engine compressor cases, causes many problems in the cutting process due to its high hardness and high toughness. Characterized by a concave cylindrical center, aircraft engine compressor cases are thin but have multiple side holes to connect with internal parts. Thus, deformation occurs despite the jig sustaining the inside. The object of this study was to lessen the deformation arising from drilling by improving the drilling jig for aircraft engine compressor cases. To this end, an aircraft engine compressor case modeled with SolidWorks was analyzed with ANSYS under real conditions. Then, to secure reliability, the analyzed deformation was compared with the actual deformation. Based on the results, the effects of the improved drilling jig for aircraft engine compressor cases were verified.

• 한국추진공학회지
• /
• 제6권3호
• /
• pp.1-7
• /
• 2002

항공기 개발초기 단계에서 주어진 항공기 임무요구도를 만족하는 최적 설계에 도달하기 위해서는 많은 엔진/기체 조합형상에 대한 적합성평가가 이루어지게 되며, 이를 위해서는 정확한 엔진장착성능을 산정할 수 있는 기법의 확립이 매우 중요하다. 본 연구에서는 초음속 항공기 개발초기 단계에서 주어진 엔진/기체 형상에 대한 엔진장착성능을 산정할 수 있는 기법을 연구하였다. 이를 위해 추력 -항력 산정 시스템(Thrust minus drag accounting system)에 의거하여 엔진 장착 추력 구성요소를 설정하고 풍동시험결과를 기초로 한 데이터베이스를 활용하여 이들 요소를 산정하였으며, 산정된 엔진 장착성능 결과를 제시하였다.

• Advances in aircraft and spacecraft science
• /
• 제7권6호
• /
• pp.553-570
• /
• 2020

To address the problems caused by the strong coupling of an airbreathing hypersonic vehicle's airframe and propulsion to the integrated control system design, an integrated airframe-propulsion model is established, and the coupling characteristics between the aircraft and engine are analyzed. First, the airframe-propulsion integration model is established based on the typical nonlinear longitudinal dynamical model of an air-breathing hypersonic vehicle and the one-dimensional dual-mode scramjet model. Thrust, moment, angle of attack, altitude, and velocity are used as transfer variables between the aircraft model and the engine model. The one-dimensional scramjet model can accurately reflect the working state of the engine and provide data to support the coupling analysis. Second, owing to the static instability of the aircraft model, the linear quadratic regulator (LQR) controller of the aircraft is designed to ensure attitude stability and height tracking. Finally, the coupling relationship between the aircraft and the engine is revealed through simulation examples. The interaction between vehicle attitude and engine working condition is analyzed, and the influence of vehicle attitude on engine safety is considered. When the engine is in a critical working state, the attitude change of the aircraft will not affect the engine safety without considering coupling, whereas when coupling is considered, the attitude change of the aircraft may cause the engine unstart, which demonstrates the significance of considering coupling characteristics.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2008년 영문 학술대회
• /
• pp.671-679
• /
• 2008

The effect of Pre-cooled Turbojet Engine installation and nozzle exhaust jet on Hypersonic Turbojet EXperimental aircraft(HYTEX aircraft) were investigated by three-dimensional numerical analyses to obtain aerodynamic characteristics of the aircraft during its in-flight condition. First, simulations of wind tunnel experiment using small scale model of the aircraft with and without the rectangular duct reproducing engine was performed at M=5.1 condition in order to validate the calculation code. Here, good agreements with experimental data were obtained regarding centerline wall pressures on the aircraft and aerodynamic coefficients of forces and moments acting on the aircraft. Next, full scale integrated analysis of the aircraft and the engine were conducted for flight Mach numbers of M=5.0, 4.0, 3.5, 3.0, and 2.0. Increasing the angle of attack $\alpha$ of the aircraft in M=5.0 flight increased the mass flow rate of the air captured at the intake due to pre-compression effect of the nose shockwave, also increasing the thrust obtained at the engine plug nozzle. Sufficient thrust for acceleration were obtained at $\alpha=3$ and 5 degrees. Increase of flight Mach number at $\alpha=0$ degrees resulted in decrease of mass flow rate captured at the engine intake, and thus decrease in thrust at the nozzle. The thrust was sufficient for acceleration at M=3.5 and lower cases. Lift force on the aircraft was increased by the integration of engine on the aircraft for all varying angles of attack or flight Mach numbers. However, the slope of lift increase when increasing flight Mach number showed decrease as flight Mach number reach to M=5.0, due to the separation shockwave at the upper surface of the aircraft. Pitch moment of the aircraft was not affected by the installation of the engines for all angles of attack at M=5.0 condition. In low Mach number cases at $\alpha=0$ degrees, installation of the engines increased the pitch moment compared to no engine configuration. Installation of the engines increased the frictional drag on the aircraft, and its percentage to the total drag ranged between 30-50% for varying angle of attack in M=5.0 flight.

• 한국압력기기공학회 논문집
• /
• 제19권2호
• /
• pp.69-74
• /
• 2023

The paper presents the results investigating the effect of aircraft engine impact location on the intended function evaluation results of spent nuclear fuel transport cask. As a result of the investigation, it is found that the structural integrity is maintained as the maximum accumulated equivalent plastic strain is below the acceptable criterion regardless of the collision location. It is identified that when the aircraft engine collided with the upper part of the transport cask without considering impact limiter the containment performance is weakened compared to when the aircraft engine collided with the central part.

• 한국추진공학회:학술대회논문집
• /
• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
• /
• pp.578-585
• /
• 2012

왕복엔진은 효율, 가격 측면의 우수한 장점으로 소형 프로펠러 항공기에서 많이 사용되고 있다. 국내에서는 KC-100, LSA, PAV, UAV등의 개발에 왕복엔진이 주요하게 사용되고 있다. 본 연구에서는 소형항공기 개념설계에 사용할 수 있는 자연 흡기, 터보차저 엔진에 대한 성능 모델을 구축하였다. 왕복엔진 항공기 순항고도에서의 비행조건을 설계점으로 적용하여 프로펠러 성능해석을 통해 최적설계를 하였으며 적합한 프로펠러 성능모델을 구축하였다. 엔진 성능 모델과 프로펠러 성능 모델의 결합을 통하여 소형왕복엔진 항공기 성능해석을 위한 통합 추진 성능 모델을 구축하였다.

• 한국자동차공학회논문집
• /
• 제3권1호
• /
• pp.108-117
• /
• 1995

The primary purpose of this extensive test effort was to observe real-time operational performance characteristics associated with automotive grade fuel utilized by piston engine powered light aviation aircraft. In fulfillment of this effort, baseline engine operations were established with 100LL aviation grade fuel followed by four blends of automotive grade fuel. A comprehensive sea-level-static test cell/flight test data collection and evaluation effort were conducted to review operational characteristics of a carbureted light aircraft piston engine as related to fuel volatility, fuel temperature, and fuel system pressure. Presented herein are results, data, and conclusions drawn from test cell engine operation as well as flight test operation on 100LL aviation grade and four blends of automotive grade fuel.

• 항공우주시스템공학회지
• /
• 제9권2호
• /
• pp.63-71
• /
• 2015

An aircraft engine is considered as the most important element among aircraft systems. Thus type certificate is required for an aircraft engine to ensure its safety under appropriate airworthiness standard. U.S. FAR Part 33 or European CS-E is widely adopted as an airworthiness standard for aircraft engines, and other representative countries of the world established own airworthiness standards under their regulations. In this paper, we compared differences of the requirements between FAR Part 33 and CS-E, and proposed the rulemaking items to harmonize Korean Airworthiness Standard for Aircraft Engines with worldwide standards and to contribute to growth of aviation industry.