Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.)最新文献_第7页

Aerodynamic shape optimization of aircraft engine nozzles based on Computer-Aided Design 基于计算机辅助设计的航空发动机喷管气动形状优化

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-2247

S. Bagy, B. Mohammadi, M. Meheut, M. Lallia, P. Coat

引用次数: 2

Simulation of a Machine Learning Based Controller for a Fixed-Wing UAV with Distributed Sensors 基于机器学习的分布式传感器固定翼无人机控制器仿真

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-1239

Ana Guerra-Langan, S. Araujo-Estrada, Arthur G. Richards, S. Windsor

{"title":"Simulation of a Machine Learning Based Controller for a Fixed-Wing UAV with Distributed Sensors","authors":"Ana Guerra-Langan, S. Araujo-Estrada, Arthur G. Richards, S. Windsor","doi":"10.2514/6.2020-1239","DOIUrl":"https://doi.org/10.2514/6.2020-1239","url":null,"abstract":"Recent research suggests that the information obtained from arrays of sensors distributed on the wing of a ﬁxed-wing small unmanned aerial vehicle (UAV) can provide information not available to conventional sensor suites. These arrays of sensors are capable of sensing the ﬂow around the aircraft and it has been indicated that they could be a potential tool to improve ﬂight control and overall ﬂight performance. However, more work needs to be carried out to fully exploit the potential of these sensors for ﬂight control. This work presents a 3 degrees-of-freedom longitudinal ﬂight dynamics and control simulation model of a small ﬁxed-wing UAV. Experimental readings of an array of pressure and strain sensors distributed across the wing were integrated in the model. This study investigated the feasibility of using machine learning to control airspeed of the UAV using the readings from the sensing array, and looked into the sensor layout and its eﬀect on the performance of the controller. It was found that an artiﬁcial neural network was able to learn to mimic a conventional airspeed controller using only distributed sensor signals, but showed better performance for controlling changes in airspeed for a constant altitude than holding airspeed during changes in altitude. The neural network could control airspeed using either pressure or strain sensor information, but having both improved robustness to increased levels of turbulence. Results showed that some strain sensors and many pressure sensors signals were not necessary to achieve good controller performance, but that the pressure sensors near the leading edge of the wing were required. Future work will focus on replacing other elements of the ﬂight control system with machine learning elements and investigate the use of reinforcement learning in place of supervised learning.","PeriodicalId":93413,"journal":{"name":"Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.)","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78242614","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: 3

Evaluation of Flight Parameters During Approach and Landing Phases by Applying Principal Component Analysis 基于主成分分析的进近和着陆阶段飞行参数评估

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-0674

S. K. Jasra, G. Valentino, A. Muscat, D. Zammit-Mangion, R. Camilleri

引用次数: 2

Evolving Material Porosity on an Additive Manufacturing Simulation with the Generalized Method of Cells 用广义单元法模拟增材制造过程中材料孔隙度的变化

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-1124

Luis F. Silva, Francisco A. Yapor Genao, E. Pineda, P. Gustafson

引用次数: 5

Nonlinear Slosh Damping Testing and Analysis for Launch Vehicle Propellant Tanks 运载火箭推进剂储罐非线性晃动阻尼试验与分析

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-2050

T. Zwieten, Jacob Brodnick, S. Reese, M. Ruth, B. Marsell, R. Parks

{"title":"Nonlinear Slosh Damping Testing and Analysis for Launch Vehicle Propellant Tanks","authors":"T. Zwieten, Jacob Brodnick, S. Reese, M. Ruth, B. Marsell, R. Parks","doi":"10.2514/6.2020-2050","DOIUrl":"https://doi.org/10.2514/6.2020-2050","url":null,"abstract":"Propellant tank slosh damping models for launch vehicle ascent analysis typically employ linear models for bare-wall damping, or assume a single, low-amplitude wave height for baffled configurations. A higher fidelity damping model would incorporate nonlinear effects to increase damping as slosh wave amplitude increases. This paper provides an overview of a technical assessment performed by the NASA Engineering and Safety Center (NESC) to evaluate lateral slosh damping as a function of lateral force (or wave) amplitude for multiple tank configurations. The increased fidelity of nonlinear slosh damping models, if leveraged, has the potential to reduce over-conservatism associated with the use of linear slosh damping models. This can provide design flexibility to enhance launch vehicle flight control performance, reduce baffle design requirements and/or increase robustness in targeted areas such as control-structure interaction during ascent. provide context for use of CFD full-scale propellant tank subscale tank test are","PeriodicalId":93413,"journal":{"name":"Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.)","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81767566","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

Identifying Optimal Equivalent Area Changes to Reduce Sonic Boom Loudness 确定最佳等效面积变化以降低音爆响度

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-0790

Troy A. Abraham, D. Hunsaker, Jonathan M. Weaver-Rosen, R. Malak

引用次数: 7

Hypersonic Boundary Layer Receptivity over a Blunt Cone to Freestream Pulse Disturbances 钝锥上高超声速边界层对自由流脉冲扰动的接受性

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-2057

Simon He, X. Zhong

{"title":"Hypersonic Boundary Layer Receptivity over a Blunt Cone to Freestream Pulse Disturbances","authors":"Simon He, X. Zhong","doi":"10.2514/6.2020-2057","DOIUrl":"https://doi.org/10.2514/6.2020-2057","url":null,"abstract":"Although receptivity plays a key role in the transition of hypersonic flows, most prior computational receptivity studies have neglected to study broadband frequency disturbance spectra. This work uses perfect gas linear stability theory (LST) and direct numerical simulation (DNS) to study the receptivity of flow over a 9.525 mm nose radius, 7 deg half-angle straight cone at Mach 10 using finite spherical and planar pulses to approximate disturbances with broadband frequency spectra. Freestream fast acoustic, slow acoustic, temperature, and vorticity pulses of both geometrieswere studied to investigate awide range of forcing conditions.UnsteadyDNSpredicts secondmodegrowth and agrees well with LST. DNS and LST data are used to extract second mode receptivity coefficients and phase spectra. For the finite pulses the strongest to weakest responses are for the fast acoustic, temperature, slow acoustic, and vorticity pulses, respectively. The planar disturbances show the strongest response for the slow acoustic, temperature, vorticity, and fast acoustic pulses in that order. Fast Fourier transform results show significant variation in the spectral disturbance response between disturbance types and geometries, and the planar fast acoustic pulse in particular is shown to much more readily excite modal disturbances other than the primary second mode.","PeriodicalId":93413,"journal":{"name":"Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.)","volume":"2015 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87817623","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: 3

Development and Simulation of Damage Tolerant Control Laws for a Compound Helicopter 复合型直升机容损控制律的研制与仿真

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-1831

Marit E. Knapp, Christina M. Ivler, J. Horn, Eric N. Johnson, D. Bridges, Mark J. S. Lopez, M. Tischler, Joseph Wagster, Kenny Cheung

{"title":"Development and Simulation of Damage Tolerant Control Laws for a Compound Helicopter","authors":"Marit E. Knapp, Christina M. Ivler, J. Horn, Eric N. Johnson, D. Bridges, Mark J. S. Lopez, M. Tischler, Joseph Wagster, Kenny Cheung","doi":"10.2514/6.2020-1831","DOIUrl":"https://doi.org/10.2514/6.2020-1831","url":null,"abstract":"A piloted simulation study was conducted to evaluate damage tolerant control (DTC) law concepts. The simulated aircraft is a ﬂy-by-wire compound utility helicopter based on the X-49A. The aircraft features auxiliary thrust through a vectored thrust ducted propeller and auxiliary lift through a wing. The conﬁguration includes a number of redundant control surfaces, including ﬂaperons and elevators that help enable DTC. This paper covers the design of the baseline inner-loop control laws, which were optimized to meet Level 1 requirements for a comprehensive set of stability, handling qualities and performance speciﬁcations. Methodology and development of the control allocation methods for DTC is presented. The ﬁxed-base piloted simulation experiment qualitatively and quantitatively evaluated the baseline control laws with various control allocation methods. Handling qualities ratings were collected using a series of maneuvers, including pitch and roll capture and tracking tasks. Survivability ratings, quantitative performance metrics, and pilot comments were collected for multiple damage scenarios in which the pilot attempted to safely land the aircraft following damage that severely limited control in one or more axes. Handling qualities ratings were also collected for the tracking tasks in the presence of damage. The paper is concluded with an overall evaluation and comparison of the damage tolerant methods.","PeriodicalId":93413,"journal":{"name":"Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.)","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88421464","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: 6

A CFD Validation Challenge for Transonic, Shock-Induced Separated Flow: Experimental Characterization 跨音速激波分离流的CFD验证挑战:实验表征

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-1309

K. Lynch, B. Lance, G. Lee, J. Naughton, N. Miller, M. Barone, S. Beresh, R. Spillers, M. Soehnel

引用次数: 4

Preliminary Measurements of the Motion of Arcjet Current Channel Using Inductive Magnetic Probes 感应磁探头对电弧电流通道运动的初步测量

Applied aerodynamics : papers presented at the AIAA SciTech Forum and Exposition 2020 : Orlando, Florida, USA, 6-10 January 2020. AIAA SciTech Forum and Exposition (2020 : Orlando, Fla.) Pub Date : 2020-01-05 DOI: 10.2514/6.2020-0919

M. Haw, J. B. Meurisse, S. Visser, Sergio Fraile Izquierdo, J. Schulz, N. Mansour

引用次数: 0