Transactions of the Japan Society for Aeronautical and Space Sciences最新文献_第3页

Random Generation of Aerodynamic Derivatives for Monte Carlo Evaluation 气动导数蒙特卡罗评价的随机生成

4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.187

Toshikazu MOTODA

{"title":"Random Generation of Aerodynamic Derivatives for Monte Carlo Evaluation","authors":"Toshikazu MOTODA","doi":"10.2322/tjsass.66.187","DOIUrl":"https://doi.org/10.2322/tjsass.66.187","url":null,"abstract":"Monte Carlo simulation (MCS) has been widely applied in the preflight evaluation of flight systems because of advantages such as its ability to evaluate nonlinear systems with uncertain parameters, which are incorporated into MCS randomly and simultaneously. Some aerodynamic and control derivatives can have significant effects on flight control and vehicle performance, so it is important to evaluate the influences of their uncertainties. However, it has not been easy to incorporate uncertainties of derivatives into MCS appropriately. A derivative is the slope of a curve, such as the Cm–α curve. To randomly vary it for use in MCS, the rotation point on the curve must be determined. However, the deviation from the nominal curve becomes greater as the flight condition, such as α, moves further from the rotation point, which can result in excessive variance of the aerodynamic coefficient. This paper presents a new method to generate derivative and bias uncertainties randomly using a covariance matrix of uncertain parameters. The method is applied to the MCS of an existing experimental flight system, and the MCS results are compared with a result that excludes derivative uncertainties to show how to apply the presented method.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134982296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Passively Adaptive Variable Rotor Diameter to Improve the Flight Performance of Variable-speed Rotors 被动自适应变旋翼直径提高变速旋翼的飞行性能

4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.226

Dong HAN, Dongxia XU, Long HE, Mingqi HUANG

{"title":"Passively Adaptive Variable Rotor Diameter to Improve the Flight Performance of Variable-speed Rotors","authors":"Dong HAN, Dongxia XU, Long HE, Mingqi HUANG","doi":"10.2322/tjsass.66.226","DOIUrl":"https://doi.org/10.2322/tjsass.66.226","url":null,"abstract":"A passively adaptive variable rotor diameter is proposed to improve the flight performance of variable-speed rotors. A validated helicopter model to predict rotor performance is utilized. The analyses focus on three typical flight states (i.e., hover, cruise, high speed) to explore the potential of the passively adaptive variable rotor diameter in reducing rotor power. During hover, the variable rotor diameter can optimize the distribution of lift and then reduce the rotor power, especially at lower rotor speeds. At a cruise speed of 150 km/h, the variable rotor diameter can delay stalling and reduce the rotor power, especially at lower rotor speeds. At a high speed of 300 km/h, the rotor speed needs to be increased, and the reduced rotor diameter is beneficial reducing power. The reduced power comes from decreasing the parasitic power of the fuselage due to decreasing its longitudinal tilt, and the rotor profile power and induced power increase with relatively small magnitudes. The passively adaptive variable rotor diameter is more suitable for larger take-off weights, and can effectively delay stalling at lower rotor speeds. The strategy of varying the rotor diameter can be designed according to the performance improvement requirements.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134982452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Addition of High-inclination, High-eccentricity Orbit Satellites to Improve QZSS Performance 增加高倾角、高偏心轨道卫星，提高QZSS性能

4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.244

Jiyeon WOO, JinHyeok JANG, Dana PARK, Sangkyung SUNG, Young Jae LEE

{"title":"Addition of High-inclination, High-eccentricity Orbit Satellites to Improve QZSS Performance","authors":"Jiyeon WOO, JinHyeok JANG, Dana PARK, Sangkyung SUNG, Young Jae LEE","doi":"10.2322/tjsass.66.244","DOIUrl":"https://doi.org/10.2322/tjsass.66.244","url":null,"abstract":"At present, Global Navigation Satellite System (GNSS) satellites operate in medium Earth orbits (MEOs), geostationary orbits (GEOs), or inclined geosynchronous orbits (IGSOs). The QZSS consists of GEO and IGSO satellites. When we considering the QZSS skyplot in Japan and its surrounding areas, there are no satellites in the northern sky. This results in a geometric placement imbalance, and thereby, causes position errors. The fundamental method to solve this problem is to position a satellite in the vacant northern area. Therefore, in this research, the addition of navigation satellites with a high-inclination, high-eccentricity orbit (a new type of orbit) is proposed. The vacant northern area can be filled effectively by adding a satellite using this orbit. Three satellites with this orbit were added to the QZSS in a simulation. Thereby, satellites were positioned effectively in the vacant northern area of the skyplot for Tokyo and Seoul. In addition, the improvement in performance was verified quantitatively through Horizontal Dilution of Precision (HDOP) and Vertical Dilution of Precision (VDOP). Accordingly, the addition of a satellite with a high-inclination, high-eccentricity orbit to the QZSS would enable more accurate positioning in Japan and its surrounding areas.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134982435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Project Irazú: Space and Ground Systems Engineering of a 1U CubeSat Store and Forward Mission for Environmental Monitoring 项目Irazú:用于环境监测的1U立方体卫星存储和转发任务的空间和地面系统工程

4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.217

Marco GOMEZ-JENKINS, Julio CALVO-ALVARADO, Adolfo CHAVES-JIMÉNEZ, Johan CARVAJAL-GODÍNEZ, Esteban MARTINEZ, Yeiner ARIAS, Ana Julieta CALVO-OBANDO, Vladimir JIMENEZ, Juan José ROJAS, Alfredo VALVERDE-SALAZAR, Julio RAMIREZ-MOLINA

{"title":"Project Irazú: Space and Ground Systems Engineering of a 1U CubeSat Store and Forward Mission for Environmental Monitoring","authors":"Marco GOMEZ-JENKINS, Julio CALVO-ALVARADO, Adolfo CHAVES-JIMÉNEZ, Johan CARVAJAL-GODÍNEZ, Esteban MARTINEZ, Yeiner ARIAS, Ana Julieta CALVO-OBANDO, Vladimir JIMENEZ, Juan José ROJAS, Alfredo VALVERDE-SALAZAR, Julio RAMIREZ-MOLINA","doi":"10.2322/tjsass.66.217","DOIUrl":"https://doi.org/10.2322/tjsass.66.217","url":null,"abstract":"Project Irazú was an innovative space mission that aimed to propel the advancement of the aerospace sector in Costa Rica, by developing a ground to space communication solution for daily monitoring of carbon fixation in forests and tree plantations. Irazú is Central America’s first satellite mission and is a joint endeavor between the Central American Association of Aeronautics and Space and the Costa Rica Institute of Technology, along with national and international partners. The 1U CubeSat developed in this project was deployed from the International Space Station on May 2018, commencing straightaway operations. The scientific mission demonstrated a practical novel solution to monitor daily tree growth by using wireless electronic sensors and a store and forward satellite link. This article presents an overview of the project, along with the mission architecture, summary of the Assembly, Integration and Testing (AI&T) and operations phases, and results from the scientific mission, including the sensor’s performance and measurements of the daily estimated tree diameter during six months. The impacts that the project had on an emerging space nation such as Costa Rica is included as well.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134982442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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

Investigation on Applying an InGaN Photocathode with Negative Electron Affinity for Electric Propulsion 负电子亲和InGaN光电阴极在电力推进中的应用研究

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.10

Y. Inoue, T. Nishitani, Anna Honda, D. Sato, H. Shikano, A. Koizumi, Y. Honda, D. Ichihara, A. Sasoh

引用次数: 1

Numerical Analysis on Axial Force Characteristics of Reusable Launch Vehicle at 150–180° Angles of Attack 150 ~ 180°攻角时可重复使用运载火箭轴向力特性数值分析

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.118

Tomohiro Mamashita, Tomotaro Muto, K. Kitamura, S. Nonaka

引用次数: 0

Influence of Amplitude of Excited Secondary Flow on the Direction of Jets 受激二次流幅值对射流方向的影响

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.37

Qiang Zhang, Y. Tamanoi, D. Kang, K. Nishibe, K. Yokota, Kotaro Sato

引用次数: 3

Visualization and Performance Evaluation of a Liquid-Ethanol Cylindrical Rotating Detonation Combustor 液体-乙醇圆柱旋转爆轰燃烧室的可视化及性能评价

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.46

K. Ishihara, Kentaro Yoneyama, Tomoki Sato, Hiroaki Watanabe, Noboru Itouyama, A. Kawasaki, K. Matsuoka, J. Kasahara, A. Matsuo, I. Funaki

引用次数: 1

Fast Prediction of Two-Dimensional Flowfields with Fuel Injection into Supersonic Crossflow via Deep Learning 基于深度学习的超声速横流二维喷油流场快速预测

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.164

Kento Akiyama, Hideaki Ogawa

引用次数: 1

Regression-Rate Evaluation of Hybrid-Rocket Fuel Grain with a Star-Fractal Swirl Port 星分形旋流口混合火箭燃料颗粒回归率评价

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2023-01-01 DOI: 10.2322/tjsass.66.61

Y. Funami, Atsushi Takano

引用次数: 0