Transactions of the Japan Society for Aeronautical and Space Sciences最新文献_第9页

Abstracts of the Papers Published in Journal of the Japan Society for Aeronautical and Space Sciences (Vol. 68, No. 6, Dec. 2020) 《日本航空航天学会学报》(第68卷第6期，2020年12月)论文摘要

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/tjsass.64.63

引用次数: 0

Fuel/Air Mixing in Reacting and Non-reacting Flows within a Dual-mode Combustor 双模燃烧室中反应流和非反应流中的燃料/空气混合

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/TJSASS.64.71

T. Arakawa, Kiyoshi Nojima, Kan Kobayashi, S. Tomioka

引用次数: 0

Jet Direction Control Using Circular Cylinder with Tangential Blowing 切向吹气圆柱射流方向控制

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/TJSASS.64.181

Qiang Zhang, Fumiya Takahashi, Kotaro Sato, W. Tsuru, K. Yokota

引用次数: 2

Effects of Propeller Position and Rotation Direction on the Ishii Wing at a Low Reynolds Number 低雷诺数下螺旋桨位置和旋转方向对石井翼的影响

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/tjsass.64.22

Koji Fujita, Kakeru Kurane, Koichi Takahashi, H. Nagai

{"title":"Effects of Propeller Position and Rotation Direction on the Ishii Wing at a Low Reynolds Number","authors":"Koji Fujita, Kakeru Kurane, Koichi Takahashi, H. Nagai","doi":"10.2322/tjsass.64.22","DOIUrl":"https://doi.org/10.2322/tjsass.64.22","url":null,"abstract":"The aerodynamic characteristics of a wing in a propeller slipstream were investigated at a low Reynolds number. The e ﬀ ects of propeller position and rotation direction on the wing were clari ﬁ ed by aerodynamic measurements and particle image velocimetry. The propeller positions were the center and tip of the wing model, whereas the rotation directions were clockwise and counterclockwise. The center propeller con ﬁ guration with a clockwise rotation showed a constant pitching moment and increased the lift-to-drag ratio. This was caused by the high-speed propeller slipstream (i.e. 12 and 10m / s on the upwash and downwash sides, respectively) and the wingtip vortex e ﬀ ect on the slipstream separation. The separation point at an angle-of-attack of 18° was delayed from x / c µ 0.1 to 0.3 by the wingtip vortex. Hence, the following two factors must be considered to enhance the aerodynamic characteristics of a Mars airplane: (i) the ratio of the area of the upwash and downwash sides of a wing in a propeller slipstream, and (ii) the e ﬀ ect of the wingtip vortex on the propeller slipstream.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68663147","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: 2

TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES .Notice Regarding Shift to Open Access 日本航空与空间科学学会学报。关于向开放获取转变的通知

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/tjsass.64.248

引用次数: 5

Droplet Size Control in Gas-Liquid Pintle Injectors 气液针式注射器中液滴尺寸的控制

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/TJSASS.64.91

Daehwan Kim, Suji Lee, Y. Yoon

{"title":"Droplet Size Control in Gas-Liquid Pintle Injectors","authors":"Daehwan Kim, Suji Lee, Y. Yoon","doi":"10.2322/TJSASS.64.91","DOIUrl":"https://doi.org/10.2322/TJSASS.64.91","url":null,"abstract":"Due to their suitable characteristics for throttleable rocket engines, interest in pintle injectors has been recently re-newed. Many studies have focused on the correlation between spraying conditions and spray or combustion characteristics for pintle injector. However, there is no previous study on the correlation between spray and combustion characteristics due to the di ﬃ culties in controlling each spray characteristic individually. This research presents a solution to this problem. For the control group, a 400 N gas-liquid pintle injector for liquid oxygen and gas methane is designed and its spray characteristics are measured through cold- ﬂ ow tests. In sequence, a ‘ reverse injection ’ idea and its design are proposed to increase spray angle while maintaining the droplet size, which is represented by the Sauter mean diameter. In addition, in the design proposed, the reverse injection e ﬀ ect is intensi ﬁ ed as the throttling level increases, decreasing the di ﬀ erence of spray angle between throttling levels. In a cold- ﬂ ow test, air and water were used under an atmospheric condition for gas-liquid ﬂ ow simulant. The spray angle and droplet size were measured using the shadow method. The ‘ reverse injection ’ feature proposed functioned properly, increasing the spray angle of the injector while maintaining the droplet size.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68664133","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: 6

Hybrid Geomagnetic Attitude and Orbit Estimation Using Time-Differential Feedback 基于差分反馈的混合地磁姿态轨道估计

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/TJSASS.64.174

Jin Wu, Chengxi Zhang, Ming Liu

{"title":"Hybrid Geomagnetic Attitude and Orbit Estimation Using Time-Differential Feedback","authors":"Jin Wu, Chengxi Zhang, Ming Liu","doi":"10.2322/TJSASS.64.174","DOIUrl":"https://doi.org/10.2322/TJSASS.64.174","url":null,"abstract":"This paper introduces a novel filter for hybrid attitude and orbit estimation of spacecrafts with geomagnetic measurements and its time-differential information. Geomagnetic measurements can be used for simultaneous attitude and orbit estimation of spacecrafts. In practice, the attitude estimation from a single magnetometer is achieved by fusing the magnetometer readings and their time derivatives together. The orbit will also be estimated according to the relationship between the geomagnetic model and spacecraft coordinates in the Earth geodetic frame. However, the magnetic time derivatives have not participated in estimating the orbit elements. According to the mathematical structures of the geomagnetic models, the time-differential feedback can effectively enhance the estimation of the velocity and thus will provide better performance for the position loop. This paper first introduces such direct feedback and formulates a new filter with better characteristics. The simulation study of a medium Earth orbit (MEO) Nadir-pointing satellite mission shows that the proposed filter achieves faster convergence and lower estimation errors.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"64 1","pages":"174-180"},"PeriodicalIF":1.1,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68662726","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: 1

Crater Detection Robust to Illumination and Shape Changes using Convolutional Neural Network 基于卷积神经网络的对光照和形状变化的鲁棒陨石坑检测

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/tjsass.64.197

T. Ishida, Masaki Takahashi, S. Fukuda

{"title":"Crater Detection Robust to Illumination and Shape Changes using Convolutional Neural Network","authors":"T. Ishida, Masaki Takahashi, S. Fukuda","doi":"10.2322/tjsass.64.197","DOIUrl":"https://doi.org/10.2322/tjsass.64.197","url":null,"abstract":"As a vast amount of data with respect to the moon and Mars is collected, exploration missions are shifting to the next step, the aim of which is a precise landing on a predetermined target. A promising technology for precision landing is terrain relative navigation (TRN), which collates landmarks detected from images and maps of landmarks. Crater detection is one of the essential technologies for TRN. A problem in detecting craters is the apparent change in craters due to illumination conditions. Another problem is the change in shape due to crater degradation. We propose a novel crater detection method based on combining a support vector machine (SVM) and a convolutional neural network (CNN) to make detection performance robust against apparent change. In the linear SVM, gradient images of a crater image dataset are learned. The learned classi ﬁ er is then used to calculate the objectness score for region proposal. Next, the CNN identi ﬁ es the image of the proposed region as to whether or not it is a crater. Our results show that the proposed method can detect craters in a wide range of illumination and shape conditions, and has better average precision than traditional crater de-tectors.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68663014","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

Modeling and Numerical Investigation of Aerodynamic Characteristics of a Propeller Circling on a Whirling Arm 螺旋桨在旋臂上旋转的气动特性建模与数值研究

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/tjsass.64.335

Yuto Itoh, A. Satoh

{"title":"Modeling and Numerical Investigation of Aerodynamic Characteristics of a Propeller Circling on a Whirling Arm","authors":"Yuto Itoh, A. Satoh","doi":"10.2322/tjsass.64.335","DOIUrl":"https://doi.org/10.2322/tjsass.64.335","url":null,"abstract":"A whirling arm is an effective device to measure propeller characteristics at low advance ratios. In the authors’ preceding research, an apparent advance ratio was adopted to determine propeller characteristics. The apparent advance ratio is determined only by the relative airspeed of the rotating arm and propeller in still air, and is used in wind tunnel measurements. However, in the case of whirling arm measurements, the advance ratio should be determined appropriately considering the additional airspeed induced by propeller wakes and swirling flow generated by the rotating arm. To address the above issue, we propose an airspeed model of blades considering velocity fields induced by the surrounding vortices. We also propose a procedure to calculate an appropriate advance ratio and the steady characteristics based on the proposed model. The validity of the proposed airspeed model is evaluated by making a comparison with the results of wind tunnel experiments. The corrected propeller characteristics using our airspeed model shows good consistency with the data referred from an existing propeller characteristics database.","PeriodicalId":54419,"journal":{"name":"Transactions of the Japan Society for Aeronautical and Space Sciences","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68664033","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: 1

Abstracts of the Papers Published in Journal of the Japan Society for Aeronautical and Space Sciences (Vol. 69, No. 3, Jun. 2021) 《日本航空航天学会学报》(第69卷第3期，2021年6月)论文摘要

IF 1.1 4区工程技术

Transactions of the Japan Society for Aeronautical and Space Sciences Pub Date : 2021-01-01 DOI: 10.2322/tjsass.64.246

引用次数: 0