Journal of Aircraft最新文献_第10页

Control-Oriented Modeling for Flexible Aircraft 面向控制的柔性飞行器建模

IF 2.2 3区工程技术

Journal of Aircraft Pub Date : 2023-11-30 DOI: 10.2514/1.c037049

Molong Duan, Carlos E. S. Cesnik, Ilya V. Kolmanovsky, Fabio Vetrano

引用次数: 0

Large Deflection Model and Optimal Design for a Morphing Wing Leading-Edge Skin 变形机翼前缘蒙皮大挠度模型及优化设计

IF 2.2 3区工程技术

Journal of Aircraft Pub Date : 2023-11-21 DOI: 10.2514/1.c037399

Fan Yang, Hong Xiao, Guang Yang, Hongwei Guo, Rongqiang Liu, Zongquan Deng

引用次数: 0

Numerical Investigation of an Unmanned Aerial Vehicle Launch from Military Transport Aircrafts 军用运输机上无人机发射的数值研究

3区工程技术

Journal of Aircraft Pub Date : 2023-11-07 DOI: 10.2514/1.c037360

Andreas Goerttler, Christian Schnepf

引用次数: 0

On the Dynamic Behavior of Wings Incorporating Floating Wingtip Fuel Tanks 带浮动翼尖燃料箱的机翼动力学特性研究

3区工程技术

Journal of Aircraft Pub Date : 2023-11-07 DOI: 10.2514/1.c037519

Fintan Healy, Joe De Courcy, Huaiyuan Gu, Djamel Rezgui, Jonathan Cooper, Thomas Wilson, Andrea Castrichini

{"title":"On the Dynamic Behavior of Wings Incorporating Floating Wingtip Fuel Tanks","authors":"Fintan Healy, Joe De Courcy, Huaiyuan Gu, Djamel Rezgui, Jonathan Cooper, Thomas Wilson, Andrea Castrichini","doi":"10.2514/1.c037519","DOIUrl":"https://doi.org/10.2514/1.c037519","url":null,"abstract":"Recent studies have shown that semi-aeroelastic hinge devices can enable larger aircraft wingspans. Such a device would be folded on the ground to meet airport width restrictions, locked during cruise for optimal aerodynamic performance, and released during maneuvers to alleviate flight loads. In contrast, this paper uses a wind tunnel experiment to study the aeroelastic behavior of floating wingtip fuel tanks. This device consists of a freely floating wingtip with an additional mass attached in the form of a liquid-filled fuel tank. The static aeroelastic results show that altering the fuel tank’s filling level and position allows the wingtip to float at an optimal angle for aerodynamic efficiency across various angles of attack and fuel masses. Additionally, this paper shows that, with careful selection of the mass distribution of the wingtip, dynamic load alleviation comparable to the semi-aeroelastic hinge concept can be achieved during turbulence and one-minus-cosine encounters. Furthermore, the effect of fluid motion is shown to reduce incremental loads during random turbulence encounters by up to 10%; however, it has a negligible impact on the response to one-minus-cosine encounters. Such results are also confirmed by a numerical model incorporating a simple reduced-order fluid sloshing model.","PeriodicalId":14927,"journal":{"name":"Journal of Aircraft","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135539967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessment of an Open-Source Aircraft Noise Prediction Model Using Approach Phase Measurements 基于接近相位测量的开源飞机噪声预测模型评估

3区工程技术

Journal of Aircraft Pub Date : 2023-11-07 DOI: 10.2514/1.c037332

Evangelia Maria Thoma, Tomas Grönstedt, Evelyn Otero Sola, Xin Zhao

{"title":"Assessment of an Open-Source Aircraft Noise Prediction Model Using Approach Phase Measurements","authors":"Evangelia Maria Thoma, Tomas Grönstedt, Evelyn Otero Sola, Xin Zhao","doi":"10.2514/1.c037332","DOIUrl":"https://doi.org/10.2514/1.c037332","url":null,"abstract":"An open-source simulation model for aircraft noise prediction is presented and validated using backpropagated noise measurements for a state-of-the-art engine and aircraft. The validation is focused on approach procedures and was performed using ground-based noise measurements that were taken at 17 recording stations for a total of 18 consecutive flights carried out during the morning of 8 April 2021. The flights were performed using two A321neo aircraft with LEAP-1A engines. It is demonstrated that the presented noise model provides a satisfactory estimation of the source noise for varying approach configurations and flight conditions. Configurations using a greater number of high-lift devices are particularly well predicted in the mid- and high-frequency regions, whereas the lower configuration settings show greater spectral deviations, which are partly attributed to measurement uncertainties caused by the increased aircraft–microphone distance. The model can predict the overall mean total sound intensity level within a 2 dB accuracy for all configurations, while the average predicted level at each microphone differs by less than 3 dB from the measurement average, for all cases except one. Variation in aircraft speed showed to have a strong impact on the predicted total noise, which matches the well-recognized sixth-power Mach number far-field sound intensity scaling law for airframe noise models, while the measurements indicated a less significant dependency. This is mainly due to installation effects and noise reduction measures that are not included in the models. Nevertheless, the variations in the spectra of the predicted and measured noise showed similar patterns.","PeriodicalId":14927,"journal":{"name":"Journal of Aircraft","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135540009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Automatic Continuous Thrust Control for Supersonic Transport Takeoff Noise Reduction 超音速运输机起飞降噪的自动连续推力控制

3区工程技术

Journal of Aircraft Pub Date : 2023-11-05 DOI: 10.2514/1.c037394

Laurens J. A. Voet, Prakash Prashanth, Raymond L. Speth, Jayant S. Sabnis, Choon S. Tan, Steven R. H. Barrett

引用次数: 0

Design Optimization of Lambda-Wing Planform and Vortex Generators for Longitudinal Instability Alleviation 用于缓解纵向失稳的λ翼平台和涡发生器设计优化

3区工程技术

Journal of Aircraft Pub Date : 2023-11-02 DOI: 10.2514/1.c037495

Seonguk Lee, Chongam Kim

{"title":"Design Optimization of Lambda-Wing Planform and Vortex Generators for Longitudinal Instability Alleviation","authors":"Seonguk Lee, Chongam Kim","doi":"10.2514/1.c037495","DOIUrl":"https://doi.org/10.2514/1.c037495","url":null,"abstract":"This paper focuses on optimizing the planform and vortex generators (VGs) to improve longitudinal stability of the lambda-wing aircraft by alleviating pitchup. The optimizations are performed in two stages using a Reynolds-averaged Navier–Stokes (RANS) solver that can accurately capture the vortical flow structure, affecting the pitchup. First, the planform configuration is optimized to minimize the rise in the pitching moment while maintaining aerodynamic and stealth performances. The designed planform delays the pitchup by 4 deg and increases the usable lift by 31% due to the leading-edge vortex (LEV) flow over the outboard wing. Second, the VGs are installed and optimized to reduce the sudden increase in the pitching moment at high angles of attack. The designed VGs partially eliminate the separated flow and recover the LEV on the outboard wing, suppressing the radical change in the pitching moment by 75%. Some quantitative difference in aerodynamic coefficients is observed in unsteady RANS computations, but the vortical flow unsteadiness minimally affects the flow structure, and the stability improvement remains over 80%. Overall, the generation and sustainability of the LEV are critical aerodynamic factors to secure longitudinal stability in designing the lambda-wing aircraft.","PeriodicalId":14927,"journal":{"name":"Journal of Aircraft","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135974704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Data-Driven Modeling for Transonic Aeroelastic Analysis 跨声速气动弹性分析的数据驱动模型

3区工程技术

Journal of Aircraft Pub Date : 2023-10-25 DOI: 10.2514/1.c037409

Nicola Fonzi, Steven L. Brunton, Urban Fasel

引用次数: 0

Toward an Efficient Method for F-16 Limit Cycle Oscillation Prediction f16极限环振荡预测的一种有效方法

3区工程技术

Journal of Aircraft Pub Date : 2023-10-25 DOI: 10.2514/1.c037391

Daniel Kariv, Donald L. Kunz, Michael Iovnovich

引用次数: 0

Autorotation-Based Descent with Trajectory Optimization 基于自旋的轨迹优化下降

3区工程技术

Journal of Aircraft Pub Date : 2023-10-24 DOI: 10.2514/1.c036912

Susmitha Patnala, Purnanand Elango, Ranjith Mohan, None Shamrao

{"title":"Autorotation-Based Descent with Trajectory Optimization","authors":"Susmitha Patnala, Purnanand Elango, Ranjith Mohan, None Shamrao","doi":"10.2514/1.c036912","DOIUrl":"https://doi.org/10.2514/1.c036912","url":null,"abstract":"The paper investigates the unpowered descent of a rotor system through the upper atmosphere. Axial and helical trajectories are investigated in the context of fixed points as well as an optimal control problem for maximizing flight time. The mathematical model considered in the paper incorporates the fuselage degrees of freedom, dynamic inflow model, and airfoil characteristics that depend on Mach and Reynolds numbers. Considering a potential application as a descent mechanism, trajectory generation is performed to maximize the flight time. As an example, the performance in the Venusian atmosphere for rotors with different airfoil characteristics is assessed. To delineate the role of constraints, initial conditions, and aerodynamic forces on the optimal descent, the axial trajectory is studied by dividing it into two phases. The first phase corresponds to the trajectory determination through an optimization process wherein control inputs are provided such that states are within bounds. The second phase trajectory (below 70 km), although determined by solving the optimal control problem as in phase-I, is shown to be close to that achieved using control inputs corresponding to fixed points corresponding to each altitude. Apart from the axial flight, helical trajectories and corresponding fixed points are investigated using a rotating constant sideslip frame. Furthermore, optimal helical trajectories are also determined, which could be useful for rotor-based descent mechanisms. A comparison between axial and helical fixed-point solutions is also presented.","PeriodicalId":14927,"journal":{"name":"Journal of Aircraft","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135266708","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0