INCAS Bulletin最新文献_第6页

Analysis of Global Systems, Support Centers, and Weather Units Aviation 全球系统、支持中心和气象单位航空分析

INCAS Bulletin Pub Date : 2023-09-04 DOI: 10.13111/2066-8201.2023.15.3.8

G. Stroe, M. Costea

引用次数: 0

Discrete gust response analysis of SARAS aircraft SARAS飞机离散阵风响应分析

INCAS Bulletin Pub Date : 2023-09-04 DOI: 10.13111/2066-8201.2023.15.3.7

A. Seeni

引用次数: 0

Off-axis response and shear characterization of unidirectional ply-level hybrid carbon-fiber-reinforced polymer materials 单向层水平混杂碳纤维增强聚合物材料的离轴响应和剪切特性

INCAS Bulletin Pub Date : 2023-09-04 DOI: 10.13111/2066-8201.2023.15.3.3

Maria Casapu, Michel Arrigoni, Ion Fuiorea Fuiorea

{"title":"Off-axis response and shear characterization of unidirectional ply-level hybrid carbon-fiber-reinforced polymer materials","authors":"Maria Casapu, Michel Arrigoni, Ion Fuiorea Fuiorea","doi":"10.13111/2066-8201.2023.15.3.3","DOIUrl":"https://doi.org/10.13111/2066-8201.2023.15.3.3","url":null,"abstract":"Composite materials, among them Carbon Fiber Reinforced Polymers (CFRP), have become a key material in structural applications for lightweight structures such as spacecraft and aircraft.\u0000CFRP can be found under various quality grades and their mechanical performances increase with their cost and quality grade. In order to limit the costs of the material without degrading technical performances, hybridization could be of interest. However, assessing the conservation of quality standards of hybridized CFRP is crucial. This paper investigates the off-axis mechanical response of ply-level hybrid carbon composites, with varying thickness and material quality. Two types of carbon\u0000fiber prepregs were combined in the same laminate using symmetric and asymmetric stacking sequences. Monotonic quasi-static off-axis tests were performed to evaluate the non-linear stress-strain behavior of the laminates, with Digital Image Correlation used to measure strain. The apparent elastic modulus and the in-plane shear modulus were evaluated from the tensile tests at three off-axis angles.\u0000The results indicate that the hybrid laminates exhibit higher failure stress levels compared to simple laminates, with an intermediate failure strain. Overall, this study provides insights into the off-axis mechanical behavior of ply-level hybrid carbon fiber composites, with potential applications in the design of composite structures.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46915984","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

Aviation insurance industry in the global economic crisis 航空保险业在全球经济危机中

INCAS Bulletin Pub Date : 2023-06-09 DOI: 10.13111/2066-8201.2022.15.2.12

I. Caprian, Ionut Valentin Lom, Iurie Caprian

引用次数: 0

Case study of TCAS implementation in modern FMS TCAS在现代FMS中的实施案例研究

INCAS Bulletin Pub Date : 2023-06-09 DOI: 10.13111/2066-8201.2023.15.2.2

Anton Balaban, S. Berbente, Andrei Neamtu, G. Stroe, Emil Costea, I. Stefanescu, I. Andrei, Ionel Popescu

{"title":"Case study of TCAS implementation in modern FMS","authors":"Anton Balaban, S. Berbente, Andrei Neamtu, G. Stroe, Emil Costea, I. Stefanescu, I. Andrei, Ionel Popescu","doi":"10.13111/2066-8201.2023.15.2.2","DOIUrl":"https://doi.org/10.13111/2066-8201.2023.15.2.2","url":null,"abstract":"In this paper, uncertainty is included in the extended framework of global air traffic both through the action of the wind and through the incomplete determination of the aerodynamic coefficients and the inevitable imprecision involved in the execution of ATC instructions. In order to\u0000study the air conflict detection process in detail, the possibility of potential conflicts must be evaluated, considering the current state of the international airspace, and taking into account the uncertainty in\u0000calculating the future position of the aircraft. A mathematical model for predicting potential aerial conflicts is necessary for this objective. In a probabilistic framework, the mathematical model thus created could be either an empirical distribution of future aircraft positions in space or a dynamic model, such as a stochastic differential equation, that describes the movement of the aircraft and implicitly defines a distribution for the position’s future of the aircraft/ future aircraft positions. Based\u0000on the prediction model, aircraft flight safety matrices can be evaluated. The mathematical methods applied in the Detection and Resolution of Air Traffic Conflicts - CDR involve a wide range of fields, but also the appropriate modeling of physical systems such as airplanes, the codification of mathematical algorithms for conflict detection, as well as the properly applied procedures for resolving potential air conflicts.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47520287","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

Altitude-compensating axisymmetric supersonic nozzle design and flow analysis 高度补偿轴对称超声速喷嘴设计与流动分析

INCAS Bulletin Pub Date : 2023-06-09 DOI: 10.13111/2066-8201.2023.15.2.4

S. Haif, H. Kbab, Amina Benkhedda

引用次数: 0

Study on Free Vibration Analysis of a Rotating Fibre-Graphene-Reinforced Hybrid Polymer Composites Pre-Twist Shel 旋转纤维-石墨烯增强混杂聚合物复合材料预扭壳自由振动分析研究

INCAS Bulletin Pub Date : 2023-06-09 DOI: 10.13111/2066-8201.2023.15.2.14

I. RAMU, Battina N. MALLESWARARAO, J. CHANDRA SEKHAR, M. VENU, P. SENTHIL KUMAR

{"title":"Study on Free Vibration Analysis of a Rotating Fibre-Graphene-Reinforced Hybrid Polymer Composites Pre-Twist Shel","authors":"I. RAMU, Battina N. MALLESWARARAO, J. CHANDRA SEKHAR, M. VENU, P. SENTHIL KUMAR","doi":"10.13111/2066-8201.2023.15.2.14","DOIUrl":"https://doi.org/10.13111/2066-8201.2023.15.2.14","url":null,"abstract":"The present work aims to develop a computational procedure for investigating the vibration behaviour of pre-twisted laminated composite shell containing graphene inclusions in their matrix. According to nanoscopic empirical equations, graphene's mechanical properties are determined by its size dependence. It has been demonstrated that the orthotropic mechanical properties of composite laminates made from carbon fibres and hybrid matrix can be evaluated. Based on pre-twist and geometric configurations, finite element methods have been used to model hybrid materials shells that include carbon fibre, graphene, and graphene-fibre reinforcement. As part of the validation process, the proposed method is compared with other methods when possible. Finally, the vibrational behaviour of the composite shell is extracted by imposing a twisted angle on a cantilever boundary condition. An analysis of vibrations for each configuration is presented in this paper, as well as the effects of graphene inclusions on natural frequencies. As graphene volume fractions in the matrix increase, the natural frequencies of every mode also increase. When the hub radius and rotational speed are increased, the frequency parameter increases with an increase in graphene volume in the hybrid polymer composite pre-twisted shell.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135100726","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

Verification of a High-Order FEM-based CFD Code using the Method of Manufactured Solutions 使用制造解方法验证基于高阶有限元的CFD代码

INCAS Bulletin Pub Date : 2023-06-09 DOI: 10.13111/2066-8201.2023.15.2.8

Seyi F. Olatoyinbo

{"title":"Verification of a High-Order FEM-based CFD Code using the Method of Manufactured Solutions","authors":"Seyi F. Olatoyinbo","doi":"10.13111/2066-8201.2023.15.2.8","DOIUrl":"https://doi.org/10.13111/2066-8201.2023.15.2.8","url":null,"abstract":"A high-order computational fluid dynamics (CFD) code capable of solving compressible turbulent flow problems was developed. The CFD code employs the Flowfield Dependent Variation (FDV) scheme implemented in a Finite Element Method (FEM) framework. The FDV scheme is basically derived from the Lax-Wendroff Scheme (LWS) involving the replacement of LWS’s explicit time derivatives with a weighted combination of explicit and implicit time derivatives. The code utilizes linear, quadratic and cubic isoparametric quadrilateral and hexahedral Lagrange finite elements with\u0000corresponding piecewise shape functions that have formal spatial accuracy of second-order, third-order and fourth-order, respectively. In this paper, the results of observed order-of-accuracy of the implemented FDV FEM-based CFD code involving grid and polynomial order refinements on uniform Cartesian grids are reported. The Method of Manufactured Solutions (MMS) is applied to governing 2-D Euler and Navier-Stokes equations for flow cases spanning both subsonic and supersonic flow regimes. Global discretization error analyses using discrete 𝐿2 norm show that the spatial order-of-accuracy of the FDV FEM-based CFD code converges to the shape function polynomial order plus one, in excellent agreement with theory. Uniquely, this procedure establishes the wider applicability of MMS in verifying the spatial accuracy of a high-order CFD code.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43822866","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

Effect of Multiple Grooves on Aerodynamic Performance of a Low Reynolds Number UAV Propeller (Part II) 多沟槽对低雷诺数无人机螺旋桨气动性能的影响(二)

INCAS Bulletin Pub Date : 2023-06-09 DOI: 10.13111/2066-8201.2023.15.2.10

Aravind SEENI

引用次数: 0

Considerations regarding the composition of the cockpit view for a modern simulator 关于现代模拟器座舱视图组成的考虑

INCAS Bulletin Pub Date : 2023-06-09 DOI: 10.13111/2066-8201.2023.15.2.1

Anton BALABAN, Andrei NEAMTU, Sorin BERBENTE, Gabriela-Liliana STROE, Irina-Beatrice STEFANESCU, Emil COSTEA, Irina-Carmen ANDREI, Ionel POPESCU

{"title":"Considerations regarding the composition of the cockpit view for a modern simulator","authors":"Anton BALABAN, Andrei NEAMTU, Sorin BERBENTE, Gabriela-Liliana STROE, Irina-Beatrice STEFANESCU, Emil COSTEA, Irina-Carmen ANDREI, Ionel POPESCU","doi":"10.13111/2066-8201.2023.15.2.1","DOIUrl":"https://doi.org/10.13111/2066-8201.2023.15.2.1","url":null,"abstract":"This study shows how to generate images and compose images in the modern simulator room by starting multiple work sessions running at the same time so that all active server stations and the station to connect to are continuously displayed. Each server handles specific functions of the simulation process and runs a dedicated software application for its specific functions. For a supervised flight simulator, the following functions need to have dedicated applications: 1) Flight Dynamics Simulation, 2) Graphical projection, 3) Cockpit and Flight instrumentation simulation and integration, 4) Supervisor station. Out of these functions, Graphical projections and Cockpit and Flight instrumentation and integration require the most computational resources. Simulators need to present the view from a cockpit which requires a field of view of at least 180 degrees. This requires at least three displays usually in the form of projectors. In legacy implementations due to computational bottlenecks, each projector needed a dedicated computer. Similarly, the Cockpit and Flight instrumentation simulation requires usually upwards of 100 flight instrument simulations and embedded processors to be managed. In legacy implementations, one computer is needed for each piloting station. In recent implementations due to the increased performance of multi-core processors, many of these functions can be handled by single computers: the flight dynamics simulation and graphical projection functions can currently be handled by a single computer, similarly, all Cockpit and Flight instrumentation simulation and integration can be handled by another computer. Thus, a minimum of three servers are required to ensure full functionality of supervised simulation using modern computing systems.","PeriodicalId":37556,"journal":{"name":"INCAS Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135100780","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