Proceedings of the Vertical Flight Society 78th Annual Forum最新文献_第5页

Control Method of the Rotor Noise Based on Sound Pressure Cancellation 基于声压抵消的转子噪声控制方法

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17442

Yan Ding, Rui Hu, Qi-jun Zhao, Xi Chen, Guo-qing Zhao

引用次数: 0

Implementation and Linearization of a State-Space Free-Vortex Wake Model for Flapping-Wing Flight 扑翼飞行状态空间自由涡尾迹模型的实现与线性化

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17578

Umberto Saetti, J. Horn

引用次数: 0

Acceleration of Heuristic Motion Planning for Unmanned Aerial Vehicles 无人机启发式运动规划的加速研究

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17641

Neelanga Thelasingha, Kaushik Nallan, A. Julius, Sandipan Mishra

{"title":"Acceleration of Heuristic Motion Planning for Unmanned Aerial Vehicles","authors":"Neelanga Thelasingha, Kaushik Nallan, A. Julius, Sandipan Mishra","doi":"10.4050/f-0078-2022-17641","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17641","url":null,"abstract":"\u0000 In this paper, we propose a heuristic-based fast motion planning framework which can be readily incorporated by the on-board path planner of Unmanned Aerial Vehicles (UAVs) to generate safe and efficient trajectories while traversing through challenging environments cluttered with obstacles. The proposed planning technique is effective for the scenarios where the exact obstacle locations need to be detected during flight and the obstacle detection range is limited by degraded environmental conditions like fog. Unlike many kinematic based planning strategies, the generated planned trajectories can be tracked effectively as they preserve the dynamics of the UAV. The planning problem is graphically represented by discretizing input and state spaces to facilitate usage of discrete search algorithms. We also propose a heuristic calculation strategy based on dynamics relaxation to accurately encode the obstacle. The Bellman optimality condition is used to modify the heuristic to facilitate faster search. This faster planning contributes to requiring a reduced minimum obstacle detection range for receding horizon planning. The proposed algorithm has been compared against an off-the-shelf nonlinear program solver and the proposed method produced superior planning times and feasible trajectories avoiding collisions. Further, we analyzed the sub-optimality of the planned trajectories and the minimum obstacle detection range required for the receding horizon planning framework.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125736650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

XV-15 Rotor Simulation in Flow360 using the Blade Element Theory 基于叶片单元理论的Flow360中XV-15转子仿真

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17588

J. Moore, Qiqi Wang, Feilin Jia

引用次数: 0

Experimental Evaluation of the Aerodynamic Rotor/Propeller Interactions on High Speed Helicopters, Efforts and Velocity Fields Measurements 高速直升机旋翼/螺旋桨气动相互作用实验评估、力场和速度场测量

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17458

Lauriane Lefevre, A. Dazin, J. Delva, Vianney Nowinski

{"title":"Experimental Evaluation of the Aerodynamic Rotor/Propeller Interactions on High Speed Helicopters, Efforts and Velocity Fields Measurements","authors":"Lauriane Lefevre, A. Dazin, J. Delva, Vianney Nowinski","doi":"10.4050/f-0078-2022-17458","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17458","url":null,"abstract":"\u0000 This paper focuses on the experimental evaluation of the rotor/propeller interactions for hybrid compound configurations. Experiments are conducted in the ONERA L2 large size-low speed wind tunnel with a 1/7.7 Dauphin 365N model and a four-bladed small-scale propeller. Measurements are realized using two six-component balances, accelerometers, and blade pitch, flap and lead-lag angle sensors. PIV measurements are performed to visualize the velocity fields around the helicopter. Different flight conditions (wind speeds and propeller rotational speeds) have been tested. The comparison of the results obtained with an isolated main rotor and an isolated propeller with the complete assembly highlighted the influence of their interactions on their performances. In hover, the propeller is completely immersed in the rotor wake, and the thrust is therefore maximal. At low speed, the propeller is partially immersed and the flow on the propeller disk is highly asymmetrical. No direct interactions are measured at high speed, where the interactions increase the performances of the propeller due to the increased angle of attack of the flow on the propeller disk.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116585083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of Helicopter Component Fatigue Test Results to Analysis 直升机部件疲劳试验结果与分析结果的比较

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17620

J. Michael, L. Altman, N. Green

引用次数: 0

Quasi-Steady Aeromechanic Helicopter Simulations Using Mid-Fidelity Aerodynamics 基于中保真度空气动力学的准稳态直升机气动力学仿真

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17465

P. Kunze, T. Ries

{"title":"Quasi-Steady Aeromechanic Helicopter Simulations Using Mid-Fidelity Aerodynamics","authors":"P. Kunze, T. Ries","doi":"10.4050/f-0078-2022-17465","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17465","url":null,"abstract":"\u0000 A numerical simulation process based on loosely coupling a helicopter flight mechanics code and a 3D panel and free wake aerodynamics method is extended for arbitrary steady flight states and quasi-steady maneuver analysis. First, the basic coupling procedure and their building blocks are introduced. Then, the extensions for arbitrary steady flight states are illustrated and a newly developed procedure for approximate maneuver simulations using a sequence of steady aeromechanically coupled simulations is presented. The aim of this procedure is to provide a rapid method for evaluation of loads, performance and stability in the helicopter design and development process. It includes an improved physics-based modeling of aerodynamic interactions as compared to low-fidelity aerodynamics models used in comprehensive codes. At the same time the computational effort is dramatically reduced as compared to highf idelity aerodynamics methods. Finally, validation results for the coupling procedure and first applications of the maneuver simulation process are shown. The computed results are compared with flight tests and blade element momentum theory based results. In many cases the solution accuracy can be significantly improved by using the coupled simulation procedure. But for maneuvers involving fast pilot inputs or considerable translational or rotational accelerations of the helicopter, the quasi-steady coupling approach is not suitable and an extension to fully unsteady loose coupling or the implementation of a tight coupling approach is proposed.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128125833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance and Acoustics of a Stacked Rotor with Differential Collective Pitch 具有差动集体节距的堆叠转子的性能与声学

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17427

C. Johnson, G. Jacobellis, J. Sirohi, Rajneesh K. Singh

{"title":"Performance and Acoustics of a Stacked Rotor with Differential Collective Pitch","authors":"C. Johnson, G. Jacobellis, J. Sirohi, Rajneesh K. Singh","doi":"10.4050/f-0078-2022-17427","DOIUrl":"https://doi.org/10.4050/f-0078-2022-17427","url":null,"abstract":"\u0000 Performance and acoustics of a 1.108 m radius stacked rotor in hover with an axial spacing between the upper and lower rotor of 0.73 chords were measured. The differential collective pitch of the rotor system, defined as half the difference between the lower rotor pitch and upper rotor pitch was varied along with the azimuthal spacing between the upper and lower blade sets. Coupled comprehensive analysis and acoustics simulations were conducted using the Rotorcraft Comprehensive Analysis System (RCAS), the acoustic solver PSU-WOPWOP, and the broadband noise module from The University of Maryland Acoustic Code (ACUM). Increased sensitivity to azimuthal spacing was observed for large, negative differential collectives, resulting in 76.5% change in thrust and 46% change in power over 11.25?change in azimuthal spacing. The trends in individual and total system thrust were predicted with good accuracy, but the total power tended to be overpredicted. Overall sound pressure level decreased by 3.5 dB at ?2? differential collective and 90?azimuthal spacing due to reduced broadband levels, indicating a possible quiet mode of operation for this type of rotor. Acoustic predictions captured thickness and loading noise trends, but significantly underpredicted broadband levels.\u0000","PeriodicalId":223727,"journal":{"name":"Proceedings of the Vertical Flight Society 78th Annual Forum","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132530784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Individual Differences in Cueing Utilization in Rotary-Wing Aviators 旋翼飞行员线索利用的个体差异

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17509

Kathryn A. Feltman, Jason Baggs, Michael Wilson

引用次数: 0

Design of a Rotary Engine Based High-Power Density Hybrid-Electric Power Generation Testbed 基于旋转发动机的大功率密度混合动力发电试验台设计

Proceedings of the Vertical Flight Society 78th Annual Forum Pub Date : 2022-05-10 DOI: 10.4050/f-0078-2022-17532

Roydon Fernandes, Jayaprakash Shivakumar, Mariana Gehrmann, N. Miller, Kule Collins, P. Currier, R. Anderson

引用次数: 0