Aerotecnica Missili & Spazio最新文献_第9页

AIDAA News #17 AIDAA新闻#17

Aerotecnica Missili & Spazio Pub Date : 2023-01-19 DOI: 10.1007/s42496-023-00147-8

Marco Petrolo

引用次数: 0

Aerotecnica M&S 100 Years Ago: A Study on the Possibility of a Dynamic Gliding Flight Aerotecnica M&S 100年前：关于动态滑翔飞行可能性的研究

Aerotecnica Missili & Spazio Pub Date : 2022-12-19 DOI: 10.1007/s42496-022-00143-4

Aldo Frediani, Vittorio Cipolla, Sergio De Rosa, Paolo Gasbarri

引用次数: 0

AIDAA News #16 AIDAA新闻#16

Aerotecnica Missili & Spazio Pub Date : 2022-12-01 DOI: 10.1007/s42496-022-00144-3

Marco Petrolo

引用次数: 0

Aerotecnica M&S 100 Years Ago: Air Navigation and Debate Between Airship and Airplane Aerotecnica M&S 100年前：航空导航与飞艇与飞机之争

Aerotecnica Missili & Spazio Pub Date : 2022-11-12 DOI: 10.1007/s42496-022-00142-5

Aldo Frediani

引用次数: 0

Numerical Simulations of Fuel Shape Change and Swirling Flows in Paraffin/Oxygen Hybrid Rocket Engines 石蜡/氧混合火箭发动机燃料形态变化及旋流的数值模拟

Aerotecnica Missili & Spazio Pub Date : 2022-10-20 DOI: 10.1007/s42496-022-00141-6

Marco Fabiani, Giorgio Gubernari, Mario Tindaro Migliorino, Daniele Bianchi, Francesco Nasuti

引用次数: 2

An Experimental and Numerical Study of the Aerodynamic Interaction Between Tandem Overlapping Propellers 串联重叠螺旋桨气动相互作用的实验与数值研究

Aerotecnica Missili & Spazio Pub Date : 2022-10-17 DOI: 10.1007/s42496-022-00138-1

Davide Algarotti

{"title":"An Experimental and Numerical Study of the Aerodynamic Interaction Between Tandem Overlapping Propellers","authors":"Davide Algarotti","doi":"10.1007/s42496-022-00138-1","DOIUrl":"10.1007/s42496-022-00138-1","url":null,"abstract":"<div><p>The latest trends of Urban Air Mobility pushed the aeronautical industrial sector towards the eVTOL concept, i.e. electrical vertical take-off and landing. Electrical power, tilt-wing configuration and multiple propellers in tandem configuration, i.e. with the propellers placed one after the other, are the key features of such concept. In particular, the presence of multiple propellers working at close range introduces a new challenge: the investigation of the rotor-rotor aerodynamic interaction between front propeller slipstreams and rear propellers. This topic is rather new, thus a lack of experimental literature is noticed. The present work aims to partially fill the gap through an extensive experimental activity which investigates the main physical aspects of the phenomenon in a typical eVTOL configuration. A dedicated wind tunnel testing campaign is performed to investigate deeply the interaction between two co-rotating tandem propellers at fixed axial distance and variable lateral separation. The performance of the tandem propellers were compared with an isolated configuration both in terms of thrust and torque measurements and Particle Image Velocimetry (PIV) surveys. The experimental results are the first step in the creation of a reference database for the validation of numerical codes implemented during the design phase of such vehicles. Load measurements showed a significant loss in the rear propeller performance as a function of the overlapping ratio between the propellers. Furthermore a dedicated spectral analysis of wind tunnel thrust signals outlined high amplitude fluctuations in partial overlapping configurations. In parallel a numerical activity was performed using a mid-fidelity aerodynamic solver relying upon Vortex Particle Method (VPM) in order to enhance the comprehension of the phenomenon. The analysis of the numerical results allowed to access the flow behaviour involving the front propeller slipstream and the rear propeller disk, which is responsible of the massive losses experienced by the rear propeller.</p></div>","PeriodicalId":100054,"journal":{"name":"Aerotecnica Missili & Spazio","volume":"102 1","pages":"77 - 89"},"PeriodicalIF":0.0,"publicationDate":"2022-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50035054","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

A Novel Visual-Based Terrain Relative Navigation System for Planetary Applications Based on Mask R-CNN and Projective Invariants 基于Mask R-CNN和投影不变量的行星地形相对导航系统

Aerotecnica Missili & Spazio Pub Date : 2022-10-15 DOI: 10.1007/s42496-022-00139-0

Roberto Del Prete, Alfredo Renga

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引用次数: 1

Autonomous Wheel Off-Loading Strategies for Deep-Space CubeSats 深空立方体卫星的自主车轮卸载策略

Aerotecnica Missili & Spazio Pub Date : 2022-09-26 DOI: 10.1007/s42496-022-00137-2

Andrea Pizzetti, Antonio Rizza, Francesco Topputo

{"title":"Autonomous Wheel Off-Loading Strategies for Deep-Space CubeSats","authors":"Andrea Pizzetti, Antonio Rizza, Francesco Topputo","doi":"10.1007/s42496-022-00137-2","DOIUrl":"10.1007/s42496-022-00137-2","url":null,"abstract":"<div><p>Deep-space CubeSats missions require careful trade-offs on design drivers such as mass, volume, and cost, while ensuring autonomous operations. This work elaborates the possibility of off-loading the reaction wheels without the need of carrying a bulky and expensive reaction control system or the field-dependent magnetotorquers. The momentum accumulated along two body axes can be removed by either offsetting the main thruster with a gimbal mechanism or by tilting differentially the solar wings. The dumping on the third axis can be still accomplished by imposing a specific attitude trajectory with the motion of either the gimbal or the arrays drive mechanism. The M-Argo CubeSat is selected as case study to test the techniques along its deep-space trajectory. The strategies decision-making is autonomously carried out by a state machine. The off-loading during the cruising arcs employs the gimballed thruster and takes typically 3 h, granting a mass savings of more than 99% with respect to the usage of a reaction control system. The trajectory is shown to have negligible differences with respect to the nominal one, since the thrust is corrected accordingly. During the coasting arcs, the solar arrays are tilted and several hours are required, depending on the Sun direction and intensity, but the propellant is completely saved. Sensitivity analyses are also carried out on the initial angular momentum components and the center of mass displacement to check the robustness of the algorithms.</p></div>","PeriodicalId":100054,"journal":{"name":"Aerotecnica Missili & Spazio","volume":"102 1","pages":"3 - 15"},"PeriodicalIF":0.0,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s42496-022-00137-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50516654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Theoretical and Numerical Modeling of Multicomponent Transcritical Diffuse Interfaces Under LRE Conditions LRE条件下多组分跨临界扩散界面的理论和数值模拟

Aerotecnica Missili & Spazio Pub Date : 2022-09-10 DOI: 10.1007/s42496-022-00136-3

Davide Cavalieri

{"title":"Theoretical and Numerical Modeling of Multicomponent Transcritical Diffuse Interfaces Under LRE Conditions","authors":"Davide Cavalieri","doi":"10.1007/s42496-022-00136-3","DOIUrl":"10.1007/s42496-022-00136-3","url":null,"abstract":"<div><p>In this study, a theoretical and numerical framework for simulating transcritical flows under a variety of conditions of interest for aerospace propulsion applications is presented. A real-fluid multicomponent and multiphase thermodynamic model, based on a cubic equation of state (EoS) and vapor–liquid equilibrium (VLE) assumptions, is presented to describe transcritical mixtures properties. The versatility of this thermodynamic model is reported since it can represent at the same time the supercritical states as well as subcritical stable two-phase states at equilibrium, via a homogeneous mixture approach. The effect this model has on the evaluation of the thermophysical variables will be emphasized. From the Computational Fluid Dynamics (CFD) point of view, the well-known numerical challenges that arise with the coupling between real-fluid thermodynamics and governing equations under transcritical conditions, are addressed by comparing a fully conservative (FC) to a quasi-conservative (QC) numerical schemes, in the context of the advection problem of a transcritical contact discontinuity.</p></div>","PeriodicalId":100054,"journal":{"name":"Aerotecnica Missili & Spazio","volume":"102 1","pages":"45 - 57"},"PeriodicalIF":0.0,"publicationDate":"2022-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s42496-022-00136-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50470010","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cassini Bistatic Radar Experiments: Preliminary Results on Titan’s Polar Regions 卡西尼双基地雷达实验：泰坦极地的初步结果

Aerotecnica Missili & Spazio Pub Date : 2022-09-10 DOI: 10.1007/s42496-022-00135-4

Giancorrado Brighi

{"title":"Cassini Bistatic Radar Experiments: Preliminary Results on Titan’s Polar Regions","authors":"Giancorrado Brighi","doi":"10.1007/s42496-022-00135-4","DOIUrl":"10.1007/s42496-022-00135-4","url":null,"abstract":"<div><p>In bistatic radar observations, reflected echoes from the surface of a target planet can be analyzed to infer its surface statistics and near-surface constituents. In this work, a preliminary inspection of two X-band bistatic radar observations gathered by the Cassini spacecraft about Titan’s polar regions is presented. Profiles of relative dielectric constant and root-mean-square (rms) surface slope are provided as outputs of the analysis, discussed, and compared with the present knowledge of Titan geomorphology. For the assessment of the rms slope, proportional to the spectral broadening of reflected echoes, a basic fitting procedure was applied to the received spectra using a Gaussian template, to later evaluate the full-width half-maximum of the fitting curve. The dielectric constant was computed from the power ratio between orthogonally circularly polarized components of signal reflections from Titan. Dielectric constant estimates are, on average, consistent with the expected materials covering the dry surfaces of the planet, while slightly low values were found over the seas. The rms slopes are generally low compared to past bistatic observations of other targets. Titan’s north polar seas are revealed to feature an unprecedented smoothness, with 0.01<span>(^circ)</span> of slope as an upper bound. Similar values were inferred for isolated spots in the southern pole, hinting at the possible presence of basins filled with liquid hydrocarbons. The main issues with the analysis are emphasized throughout the document, and some ideas for future work are presented in the conclusions.</p></div>","PeriodicalId":100054,"journal":{"name":"Aerotecnica Missili & Spazio","volume":"102 1","pages":"59 - 76"},"PeriodicalIF":0.0,"publicationDate":"2022-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s42496-022-00135-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50470475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0