Aerospace Science and Technology最新文献

{"title":"A nonlinear filter based on GSK for relative navigation using relative orbital elements","authors":"Bing Hua,&nbsp;Xue Gao,&nbsp;Xiaosong Wei","doi":"10.1016/j.ast.2024.109692","DOIUrl":"10.1016/j.ast.2024.109692","url":null,"abstract":"<div><div>Due to the sensitivity of the relative orbital elements model to the measurement noise, the non-stationary heavy-tailed noise(NSHT) induced by the time-varying environment during the relative navigation usually leads to filter divergence. To address this problem, a new nonlinear filter based on Gaussian-Student's-Multivariate K(GSK) mixture distribution is proposed in this paper. A Dirichlet stochastic mixture vector fusing Gaussian, Student's t, and Multivariate K distributions is introduced, thus proposing a GSK mixture distribution modeling measurement likelihood; then the Kullback-Leibler Divergence (KLD) of the true posteriori probability density function(PDF) and the approximate posteriori PDF are minimized by a variational Bayesian(VB) technique to solve for the state and parameter approximate a posteriori estimations, and finally a new nonlinear filter based on the GSK mixture distribution is derived for angles-only relative navigation in time-varying environments. Simulation outcomes indicate that the filter can realize state estimation in non-stationary states effectively with 45.16% higher estimation accuracy than the existing advanced filters.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109692"},"PeriodicalIF":5.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142593645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing the efficiency and energy capacity of the tri-directional FG nanoplate attached to the piezoelectric patch validated by artificial intelligence","authors":"Wenqing Yang ,&nbsp;Lei Chang ,&nbsp;Khalid A. Alnowibet ,&nbsp;Mohammed El-Meligy","doi":"10.1016/j.ast.2024.109694","DOIUrl":"10.1016/j.ast.2024.109694","url":null,"abstract":"<div><div>Enhancing the efficiency and energy capacity in composite nanoelectromechanical systems (NEMS) holds significant importance in the engineering industry due to its critical role in enhancing the performance, reliability, and safety of aerospace structures and systems. One key area of application is in the development of advanced sensors and actuators. Regarding this issue, in the current work, enhancing the efficiency and energy capacity in the sandwich nanoplate with a tri-directional functionally graded layer and a piezoelectric patch layer is presented. For capturing the size effects, nonlocal strain-stress gradient theory with two size-dependent factors has been presented. The transverse shear deformation factor has an important role in the prediction of the mechanical performance of various structures. So, in the current work, a new four-variable refined quasi-3D logarithmic shear deformation theory has been investigated. Also, for coupling the piezoelectric patch and composite structure, compatibility conditions have been presented. Hamilton's principle with three factors has been presented for obtaining the coupled governing equations of the NEMS. For solving the current electrical system's partial differential equations, an analytical solution procedure has been presented. Also, to have a better understanding of the current electrical system's fundamental frequency, COMSOL tri-physics simulation has been presented. For verification of the results, one of the tools of artificial intelligence via the datasets of the mathematics and COMSOL multi-physics simulations is presented to verify the results for other input data with low computational cost. Finally, the effects of various factors such as the geometry of the piezoelectric patch, FG power index, length scale factor, nonlocal parameter, and location of the piezoelectric patch on the phase velocity have been discussed in detail. One of the important outcomes of the current work is that designers for modeling the NEMS should pay attention to the applied voltage, location, and geometry of the piezoelectric patch.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109694"},"PeriodicalIF":5.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the transition mechanism of vibrating low-pressure turbine blades based on large Eddy simulation","authors":"Zhang Yingqiang ,&nbsp;Dong Xu ,&nbsp;Wu Xuan ,&nbsp;Zhang Yanfeng ,&nbsp;LU Xingen ,&nbsp;ZHU Junqiang","doi":"10.1016/j.ast.2024.109695","DOIUrl":"10.1016/j.ast.2024.109695","url":null,"abstract":"<div><div>The low-pressure turbine blades are susceptible to vibration issues due to their thin profiles and large aspect ratios. Blade vibration will significantly affect the evolution of the boundary layer and the flow state. This paper utilizes large eddy simulation to predict the development of the boundary layer on the suction side of low-pressure turbine blades at low Reynolds numbers (<em>Re</em> = 25,000). It introduces different vibration cases to elucidate the mechanisms by which blade vibrations influence boundary layer separation and transition. The study demonstrates that the introduction of vibration cases significantly reduces both the size of the overall spanwise vortices and their roll-up height. A staggered distribution of spanwise vortices, characterized by alternating high and low regions, is observed near the trailing edge of the vibrating blades. The shorter spanwise vortices develop rapidly, nearly traversing the process of hairpin vortices (Λ vortex) generation and development, and directly breaking down into smaller-scale vortices. This accelerates the transition process. Blade vibration primarily promotes turbulence reattachment by facilitating the transition process dominated by the K-H instability mechanism within the separating shear layer. Consequently, it effectively restricts the growth of the separation bubble on the suction side of the blades, significantly reducing aerodynamic losses. Moreover, increasing the vibration frequency within a certain range can amplify these effects, achieving up to a 23% reduction in total pressure loss compared to stationary blades.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109695"},"PeriodicalIF":5.0,"publicationDate":"2024-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the flutter characteristics of folding wings with variable swept angles of the outer wing","authors":"Jin-Gang Wang,&nbsp;Xiang-Ying Guo","doi":"10.1016/j.ast.2024.109685","DOIUrl":"10.1016/j.ast.2024.109685","url":null,"abstract":"<div><div>The critical flutter speed, along with the associated stability and safety of a folding-wing aircraft, has been evaluated for variable wing configurations based on traditional designs. Through theoretical analysis and numerical simulation validation, the contributions of parameters such as the hinge stiffness, sweep angle, and folding angle on the flutter and stability of the folding wing are investigated in detail. It is observed that under a specified safe hinge stiffness, the proposed variable-sweep folding-wing configuration can enhance the critical flutter speed at a dangerous folding angle. Through the joint manipulation of the folding and sweep angles, the aerodynamic drag of the folding wing was reduced, thereby enhancing its flight speed and flutter boundaries. This paper aims to provide novel insights into the design and stability analysis of variable-wing configurations.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109685"},"PeriodicalIF":5.0,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Point-enhanced convolutional neural network: A novel deep learning method for transonic wall-bounded flows","authors":"Fernando Tejero,&nbsp;Sanjeeth Sureshbabu,&nbsp;Luca Boscagli,&nbsp;David MacManus","doi":"10.1016/j.ast.2024.109689","DOIUrl":"10.1016/j.ast.2024.109689","url":null,"abstract":"<div><div>Low order models can be used to accelerate engineering design processes. Ideally, these surrogates should meet the conflicting requirements of large design space coverage, high accuracy and fast evaluation. Within the context of aerospace applications at transonic conditions, this can be challenging due to the associated non-linearity of the flow regime. Different methods have been investigated in the past to predict the flow-field around shapes such as airfoils or cylinders. However, they usually have reduced spatial resolution, limiting the prediction capabilities within the boundary layer which is of interest for transonic wall-bounded flows. This work proposes a novel Point-Enhanced Convolutional Neural Network (PCNN) method that combines the advantages of the well-established PointNet and convolutional neural network approaches. The PCNN model has relatively low memory requirements in the training process, preserves the spatial correlation in the domain and has the same resolution as a traditional computational method. The architecture is used for the flow-field prediction of civil aero-engine nacelles in which it is demonstrated that the flow features of peak isentropic Mach number (<span><math><msub><mrow><mi>M</mi></mrow><mrow><mi>i</mi><mi>s</mi></mrow></msub></math></span>), pre-shock isentropic Mach number and shock location (<span><math><mi>X</mi><mo>/</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>n</mi><mi>a</mi><mi>c</mi></mrow></msub></math></span>) are captured within <span><math><mi>Δ</mi><msub><mrow><mi>M</mi></mrow><mrow><mi>i</mi><mi>s</mi></mrow></msub></math></span> = 0.02, <span><math><mi>Δ</mi><msub><mrow><mi>M</mi></mrow><mrow><mi>i</mi><mi>s</mi></mrow></msub><mo>=</mo><mn>0.04</mn></math></span>, <span><math><mi>Δ</mi><mi>X</mi><mo>/</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>n</mi><mi>a</mi><mi>c</mi></mrow></msub><mo>=</mo><mn>0.007</mn></math></span>, respectively. The PCNN model successfully predicts the integral parameters of the boundary layer, in which the incompressible displacement thickness, momentum thickness and shape factor are typically within 5% of the CFD. Overall, the PCNN method is demonstrated for transonic wall-bounded flows for a range of flow physics that include shock waves and shock-induced separation.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109689"},"PeriodicalIF":5.0,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Active maneuver load alleviation for a pitching wing via spanwise-distributed camber morphing","authors":"You Wu ,&nbsp;Jinying Li ,&nbsp;Yuting Dai ,&nbsp;Yongchang Li ,&nbsp;Chao Yang","doi":"10.1016/j.ast.2024.109693","DOIUrl":"10.1016/j.ast.2024.109693","url":null,"abstract":"<div><div>This paper presents the design and verification of a nonlinear model inversion (NMI) controller for the maneuver load alleviation of a pitching oscillating wing based on spanwise-distributed active camber morphing. Recurrent neural networks (RNNs) are used to predict nonlinear and unsteady aerodynamic forces due to wing's large amplitude pitching maneuver, and a fully connected neural network is introduced to build the dynamic inversion of the aeroelastic system for control law design. The inversed system is concatenated with a PI controller to assemble a nonlinear active controller. The controller is first utilized in an offline environment for a 1DoF pitching finite-span wing with spanwise-distributed active camber morphing and then verified in CFD-based fluid-structure-control coupling simulation. The results show that the offline controller could eliminate the maneuver load. In the online CFD-based fluid-structure-control simulation, the bending moment can be alleviated by 38%.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109693"},"PeriodicalIF":5.0,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142586025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient fuzzy simulations for estimating the failure credibility of engineering structures under fuzzy environment","authors":"Yujie Gu ,&nbsp;Menghao Xue ,&nbsp;Yunwen Miao ,&nbsp;Mingxuan Zhao ,&nbsp;Qing Ma","doi":"10.1016/j.ast.2024.109688","DOIUrl":"10.1016/j.ast.2024.109688","url":null,"abstract":"<div><div>Efficiently and accurately solving the failure credibility of a structural system plays a significant role in the engineering field under fuzzy environment. A more precise failure credibility can help assess the safety degree of the system, and then reduce the occurrence of security accidents. At present, the extended fuzzy first-order and second-moment method (EFFOSM) is effective to analyze failure credibility for some occasions. However, when it comes to complicated performance functions and fuzzy inputs, the accuracy of EFFOSM is greatly reduced and its efficiency also needs to be improved. To overcome the above shortcomings, this paper proposes two types of novel fuzzy simulation algorithms, namely uniform discretization algorithm (UDA) and bisection simulation algorithm (BSA). For the system involving frequently-encountered continuous and strictly monotone performance functions of regular LR fuzzy interval inputs, these two algorithms are designed to estimate failure credibility with higher efficiency and accuracy. Subsequently, with the aid of the linearization and regularization procedures in EFFOSM, the application of UDA and BSA is extended to non-monotone performance functions of irregular LR fuzzy intervals. To evaluate and verify the performance of the proposed two algorithms, their comparisons with EFFOSM are conducted through some numerical examples and practical problems. The results show that the proposed two algorithms outperform EFFOSM in terms of accuracy and efficiency, and also have wider application range for estimating the failure credibility of strictly monotone performance functions involving regular LR fuzzy interval inputs. Meanwhile, BSA is slightly better than UDA for the less runtime.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109688"},"PeriodicalIF":5.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Additively-manufactured shear tri-coaxial rocket injector mixing and combustion characteristics","authors":"Alex R. Keller ,&nbsp;Fabio A. Bendana ,&nbsp;Vincent C. Phong ,&nbsp;R. Mitchell Spearrin","doi":"10.1016/j.ast.2024.109680","DOIUrl":"10.1016/j.ast.2024.109680","url":null,"abstract":"<div><div>A monolithic tri-coaxial propellant injection scheme for enhanced mixing of methane-oxygen in liquid-propellant rocket systems is enabled by additive manufacturing. Mixing and combustion characteristics of the tri-coaxial design are assessed experimentally from 1–69 bar using laser absorption tomography and chemiluminescence imaging, and are compared to a traditionally-manufactured bi-coaxial design. Quantitative two-dimensional images of temperature and carbon monoxide mole fraction are generated from the laser absorption spectroscopy methods, while OH* chemiluminescence provides an approximate metric for combustion heat release defining flame length and injector standoff distance. At similar pressures and oxidizer-to-fuel ratios, the tri-coaxial injector design is shown to enhance mixing and combustion progress, reducing characteristic mixing length scales and achieving improved combustion performance relative to more conventional bi-coaxial designs. Despite enhanced mixing, the tri-coaxial design exhibits more limited reduction in flame standoff distance from the injector face, suggesting that increased heat flux to the injector face can be managed. The tri-coaxial injector highlights the potential to leverage additive manufacturing to enhance performance and simplify the fabrication of liquid-propellant rocket engines.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109680"},"PeriodicalIF":5.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear dynamic characteristics of smart FG-GPLRC sandwich varying thickness truncated conical shell with internal resonance for first three order modes","authors":"Shaowu Yang ,&nbsp;Zhiquan Wang ,&nbsp;Yuxin Hao ,&nbsp;Wei Zhang ,&nbsp;Yan Niu ,&nbsp;Wensai Ma","doi":"10.1016/j.ast.2024.109672","DOIUrl":"10.1016/j.ast.2024.109672","url":null,"abstract":"<div><div>This paper examines the 1:1:1 internal resonant nonlinear dynamic characteristic of the simply supported varying thickness functionally graded graphene platelets reinforced composite (FG-GPLRC) smart truncated sandwich conical shell subject to the combined effects of transverse load and in-plane force. The truncated smart sandwich conical shell is composed of an FG-GPLRC varying thickness core and two magneto-electro-elastic face layers, whose material properties and constitutive relations are individually identified by the rule of mixture, improved Halpin-Tsai approach and generalized Hooke's law. Utilizing the first-order shear deformation theory (FSDT), von Karman's geometrical nonlinearity, Hamilton's principle and Galerkin technique, the 3DOF dimensionless nonlinear dynamic formulations for the truncated smart FG-GPLRC conical shell are established. The multiple-scale technique is applied to developing the averaged equations for the truncated smart FG-GPLRC conical shell under combined resonance. The frequency-response and force-response curves, Poincare maps, phase portraits, time history diagrams, bifurcation and maximum Lyapunov exponent diagrams can be portrayed by the nonlinear equation solver and Runge-Kutta approach. The effects of the damping and tuning parameters, transverse and in-plane forces on the 1:1:1 internal resonant nonlinear dynamic characteristic of truncated smart varying thickness FG-GPLRC sandwich conical shell are examined.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109672"},"PeriodicalIF":5.0,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142560590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Position and reduced attitude trajectory tracking control of quadrotors: Theory and experiments","authors":"Carlos Montañez-Molina ,&nbsp;Javier Pliego-Jiménez","doi":"10.1016/j.ast.2024.109683","DOIUrl":"10.1016/j.ast.2024.109683","url":null,"abstract":"<div><div>Multirotor aerial vehicles are versatile flying robots that perform hovering, vertical take-off and landing, and aggressive maneuvers in a 3D environment. Due to their underactuated nature, the aerial vehicles' position and orientation cannot be controlled independently. For this reason, most of the quadrotors' tasks involved position tracking or regulation tasks. This paper focuses on the position-tracking problem of quadrotors using the reduced orientation of the vehicle, meaning that only two degrees of freedom of the robot's orientation are controlled. We propose an almost global exponential reduced attitude control law that aligns the aerial robot's thrust direction with the desired force that drives the robot along the desired position trajectory. For the translational subsystem, we propose a dynamic control law that drives the position and velocity of the quadrotors asymptotically to the desired trajectories. The proposed attitude control law is computationally simple, and thus, it is suitable to run on board. Finally, we provide experimental results performed on a low-cost quadrotor and a comparison study with a full-attitude controller to illustrate the performance and advantages of the proposed control laws.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"155 ","pages":"Article 109683"},"PeriodicalIF":5.0,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142534789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}