航空科学与技术(英文)最新文献_第2页

Validation of Novel Model for Identification of Thermal Conditions in the Low Corona 低日冕热条件识别新模型的验证

航空科学与技术(英文) Pub Date : 2022-01-01 DOI: 10.4236/aast.2022.71004

D. Berdichevsky, J. M. R. Gómez, L. Vieira, A. Lago

引用次数: 1

Interference Detection and Suppression Based on Time-Frequency Analysis 基于时频分析的干扰检测与抑制

航空科学与技术(英文) Pub Date : 2022-01-01 DOI: 10.4236/aast.2022.72006

Haijun Huang, K. Sun

引用次数: 0

Prediction of Aerothermal Environment and Heat Transfer for Hypersonic Vehicles with Different Aerodynamic Shapes Based on C++ 基于c++的不同气动外形高超声速飞行器气动热环境与传热预测

航空科学与技术(英文) Pub Date : 2022-01-01 DOI: 10.4236/aast.2022.73008

Tian Huang, G. He, Qi Wang

{"title":"Prediction of Aerothermal Environment and Heat Transfer for Hypersonic Vehicles with Different Aerodynamic Shapes Based on C++","authors":"Tian Huang, G. He, Qi Wang","doi":"10.4236/aast.2022.73008","DOIUrl":"https://doi.org/10.4236/aast.2022.73008","url":null,"abstract":"This research paper discusses constructing a unified framework to develop a full-rate scheme for hypersonic heating calculations. The method uses a flow tracing technique with normal phase vector adjustment in a non-structured delineated grid combined with empirical formulations for convective heat transfer standing and non-standing heat flow engineering. This is done using dev-C++ programming in the C++ language environment. Comparisons of the aerodynamic thermal environment with wind tunnel experimental data for the Space Shuttle and Apollo return capsules and standing point heat transfer measurements for the Fire II return capsule was carried out in the hypersonic Mach number range of 6 - 35 Ma. The tests were carried out on an 11th Gen Intel(R) Core(TM) i5-1135G7 processor with a valuable test time of 45 mins. The agreement is good, but due to the complexity of the space shuttle tail, the measurements are still subject to large errors compared to wind tunnel experiments. A comparison of the measured Fire-II return capsule standing-point heat values with the theory for calculating standing-point heat fluxes simulated using Fay & Riddell and wind tunnel experiments is provided to verify the validity of this procedure for hypersonic vehicle heat transfer prediction. The heat fluxes assessed using this method for different aerodynamic profiles of hypersonic vehicles agree very well with the theoretical solution.","PeriodicalId":61930,"journal":{"name":"航空科学与技术(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70453799","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

Communication System for Nanosatellite Earth Observation 纳米卫星对地观测通信系统

航空科学与技术(英文) Pub Date : 2021-07-14 DOI: 10.4236/aast.2021.63010

N. Zosimovych

引用次数: 2

Jump Drive, Replicators, Transporters, and Time Travel 跳跃驱动器、复制器、运输器和时间旅行

航空科学与技术(英文) Pub Date : 2021-07-14 DOI: 10.4236/aast.2021.63009

Y. Segman

引用次数: 1

The Truth behind the Solar System in the Universe 宇宙中太阳系背后的真相

航空科学与技术(英文) Pub Date : 2021-07-14 DOI: 10.4236/aast.2021.63011

Rami Ayoob

引用次数: 0

MARSZUG—A Space Train for Regular Delivery of Astronauts onto Mars MARSZUG-A定期将宇航员送上火星的太空列车

航空科学与技术(英文) Pub Date : 2021-05-26 DOI: 10.4236/AAST.2021.62007

A. Rubinraut

{"title":"MARSZUG—A Space Train for Regular Delivery of Astronauts onto Mars","authors":"A. Rubinraut","doi":"10.4236/AAST.2021.62007","DOIUrl":"https://doi.org/10.4236/AAST.2021.62007","url":null,"abstract":"A \u0000project of the space train MARSZUG intended for regular delivery of astronauts \u0000to Mars is considered. In the first stage of the flight, the astronauts with \u0000the help of the carrier rocket equipped with a chemical rocket engine are \u0000delivered to the international space station (ISS). To deliver astronauts from \u0000Earth’s orbit to Mars orbit, a space train design consisting of two rockets, \u0000which have superconductive magnetoplasma electric engine MARS, has been \u0000developed. For the first time, a combined propulsion system MARS-M has been \u0000developed for the train movement, allowing carrying \u0000out the pitching, yaw and rotation of the rocket. This greatly simplifies the \u0000rocket control system and increases its reliability. The energy source of the \u0000electric engines is a sliding solar panel made of gallium arsenide. Working \u0000substance to create reactive thrust of electrorocket engines—hydrogen is stored \u0000in a liquid state in the cryogenic tank located along the longitudinal axis of \u0000the rocket. In the nasal part of the front electric rocket, a shaft rotating in \u0000a superconductive bearing is located. The shaft has a cylindrical nozzle, on \u0000which with the help of docking units two takeoff-landing capsules TLC-1 and \u0000TLC-2 are installed with which help landing and takeoff from the surface of \u0000Mars is carried out. This allows astronauts to constantly stay during the \u0000flight under the influence of gravity. To refuel the space train with liquid \u0000hydrogen in the orbit of Mars, the design of a space refueler with a chemical \u0000rocket engine is developed. The developed space train is able to regularly \u0000deliver astronauts to the surface near the northern pole of Mars.","PeriodicalId":61930,"journal":{"name":"航空科学与技术(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47462185","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

A Study of the Deformation Derivatives for a Ti-6Al-4V Inertia Friction Weld Ti-6Al-4V惯性摩擦焊缝变形导数的研究

航空科学与技术(英文) Pub Date : 2021-05-26 DOI: 10.4236/AAST.2021.62008

R. Turner, N. Warnken, J. Brooks

{"title":"A Study of the Deformation Derivatives for a Ti-6Al-4V Inertia Friction Weld","authors":"R. Turner, N. Warnken, J. Brooks","doi":"10.4236/AAST.2021.62008","DOIUrl":"https://doi.org/10.4236/AAST.2021.62008","url":null,"abstract":"The \u0000velocity–versus-time rundown curves from two experimental Ti-6Al-4V inertia \u0000friction welds were analysed and differentiated several times, to produce \u0000rotational acceleration, jerk, jounce (or snap), crackle and pop versus-times \u0000curves for each weld. Titanium alloys and their mechanical properties are known \u0000to be highly sensitive to strain rate as the material is deformed, though \u0000nothing has ever been considered in terms of the higher-order time-derivatives \u0000of position. These curves have been studied and analysed further, for a more \u0000complete understanding of the derivative trends. Rotational acceleration and \u0000jerk traces both display behavior patterns across the two welds as the part \u0000rotates under action from the flywheel. The rotational snap also displays a \u0000pattern in this derivative during the final approximately 0.5 s of welding, as \u0000the energy dissipates. Evidence of a distinct oscillatory pattern in the \u0000rotational crackle and pop terms was noted for one weld when differentiating \u0000over a larger time-base, though could not be replicated in the 2nd weld. The higher derivative curves allow \u0000distinction of different process regimes, indicating that inertial energy mostly influences the time-base of dynamically steady-state phase. Qualitative differences \u0000between initial energies are evident in higher derivatives.","PeriodicalId":61930,"journal":{"name":"航空科学与技术(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41297947","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

A General Method to Compute the Electric Flux Lines between Two Magnet Wires in Close Contact and Its Application for the Evaluation of Partial Discharge Risks in the Slots of Electric Machines Embedded in Future Transportation Systems 密切接触两磁线间电通量线的一般计算方法及其在未来交通系统中嵌入式电机槽部局部放电风险评估中的应用

航空科学与技术(英文) Pub Date : 2021-02-25 DOI: 10.4236/AAST.2021.61003

P. Collin, D. Malec, Y. Lefèvre

{"title":"A General Method to Compute the Electric Flux Lines between Two Magnet Wires in Close Contact and Its Application for the Evaluation of Partial Discharge Risks in the Slots of Electric Machines Embedded in Future Transportation Systems","authors":"P. Collin, D. Malec, Y. Lefèvre","doi":"10.4236/AAST.2021.61003","DOIUrl":"https://doi.org/10.4236/AAST.2021.61003","url":null,"abstract":"The sizing of the Electrical Insulation System (EIS) is an important \u0000challenge in electric motors of higher specific power \u0000driven by faster inverters. That keeps increasing the electric stress which the winding is submitted in the stator \u0000slot. Consequently, Partial Discharges (PD) are more likely to occur. Nowadays, the Paschen’s criterion is widely used to \u0000evaluate the risk of partial discharge. It requires the knowledge of electric field lines. This paper presents a method \u0000to precisely compute the electric field lines in a two-dimensional (2D) \u0000electrostatic problem. The field of study is composed of two magnet wires in \u0000close contact. Such configuration is representative of the turn-to-turn interaction in an electric motor slot. The problem \u0000is solved using the scalar potential formulation only. The notion of flux tubes \u0000is used for the post process of the electric field lines in a developed numerical code on Matlab. The \u0000developed method is compared to a ballistic method already included on Matlab. \u0000The work presented here is included in an automatic tool to suppress or reduce \u0000the partial discharge risk in a stator slot of high power density motor destined for future transportation systems.","PeriodicalId":61930,"journal":{"name":"航空科学与技术(英文)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46438858","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

Design Technology Research of Aircraft Engine Health Management (EHM) Technologies 航空发动机健康管理技术的设计技术研究

航空科学与技术(英文) Pub Date : 2021-02-25 DOI: 10.4236/AAST.2021.61002

Wessam Abousada

引用次数: 2