Aerospace Science and Technology最新文献_第4页

Shock wave and fully turbulent boundary layer interaction controlled by surface arc plasma actuation 由表面电弧等离子体驱动控制的冲击波和全湍流边界层相互作用

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.ast.2024.109687

Qiong Wang, Tian Gan, Xiaoyue Xie

Experiments were performed to examine the control effect of surface arc plasma actuators on a fully turbulent boundary layer interaction over a 26-deg ramp in a supersonic flow. The experiments utilized a non-invasive schlieren measurement device, along with comprehensive statistical processing techniques. Time-resolved schlieren up to 25 kHz were performed for visualization. Root Mean Square (RMS), Fast Fourier Transformation (FFT), and Proper Orthogonal Decomposition (POD) were performed on the schlieren dataset for structure identification in the interaction flow. A discharge is created between an electrode pair located upstream of a ramp to induce significant disturbances in the turbulent boundary layer. The discharge frequencies employed are f_a=0.5, 1, 2, and 5 kHz. The findings indicate that lower excitation frequencies result in a greater instantaneous energy input to the flow field, while the highest cumulative energy is obtained at 5 kHz over time. The separation region inhibited effect is further verified through the RMS of the schlieren intensity. The separation shock weaken is verified through the FFT of the schlieren intensity. The results indicate that perturbations in the fully turbulent boundary layer interaction flow pattern are more effective for separation shock control and separation region inhibition. It is important to appropriately increase the actuation frequency in order to achieve a certain level of control over the reattachment shock. This control effect is dependent on the total energy injected into the flow field rather than a large energy of a single pulse.

实验研究了表面电弧等离子体致动器对超音速气流中 26 度斜坡上完全湍流边界层相互作用的控制效果。实验采用了非侵入式离层仪和综合统计处理技术。为实现可视化，进行了高达 25 kHz 的时间分辨离层测量。对裂隙数据集进行了均方根（RMS）、快速傅里叶变换（FFT）和适当正交分解（POD），以识别相互作用流中的结构。在位于斜坡上游的一对电极之间产生放电，以引起湍流边界层的显著扰动。放电频率分别为 fa=0.5、1、2 和 5 kHz。研究结果表明，较低的激励频率会给流场带来更大的瞬时能量输入，而随着时间的推移，5 kHz 时的累积能量最高。分离区域的抑制效应通过裂隙强度的有效值得到了进一步验证。分离冲击的减弱通过 Schlieren 强度的 FFT 得到验证。结果表明，完全湍流边界层相互作用流模式的扰动对分离冲击控制和分离区域抑制更有效。重要的是要适当提高致动频率，以便对重新附着冲击实现一定程度的控制。这种控制效果取决于注入流场的总能量，而不是单个脉冲的大能量。

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引用次数: 0

A nonlinear filter based on GSK for relative navigation using relative orbital elements 基于 GSK 的非线性滤波器，用于利用相对轨道要素进行相对导航

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.ast.2024.109692

Bing Hua, Xue Gao, Xiaosong Wei

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.

由于相对轨道要素模型对测量噪声的敏感性，相对导航过程中由时变环境引起的非稳态重尾噪声（NSHT）通常会导致滤波器发散。针对这一问题，本文提出了一种基于高斯-学生-多变量 K（GSK）混合分布的新型非线性滤波器。本文引入了一种融合高斯分布、Student's t 分布和多元 K 分布的 Dirichlet 随机混合向量，从而提出了一种模拟测量似然的 GSK 混合分布；然后通过变异贝叶斯（VB）技术最小化真实后验概率密度函数（PDF）和近似后验概率密度函数（PDF）的库尔贝-莱布勒发散（KLD），求解状态和参数的近似后验估计值，最后推导出一种基于 GSK 混合分布的新型非线性滤波器，用于时变环境中的只角相对导航。仿真结果表明，该滤波器能有效实现非平稳状态下的状态估计，估计精度比现有的高级滤波器高 45.16%。

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引用次数: 0

Enhancing the efficiency and energy capacity of the tri-directional FG nanoplate attached to the piezoelectric patch validated by artificial intelligence 通过人工智能验证提高连接到压电贴片的三向 FG 纳米板的效率和能量容量

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-28 DOI: 10.1016/j.ast.2024.109694

Wenqing Yang , Lei Chang , Khalid A. Alnowibet , Mohammed El-Meligy

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.

提高复合纳米机电系统（NEMS）的效率和能量容量在工程行业具有重要意义，因为它在提高航空航天结构和系统的性能、可靠性和安全性方面发挥着关键作用。其中一个关键应用领域是开发先进的传感器和致动器。针对这一问题，目前的研究工作介绍了如何利用三向功能分级层和压电贴片层提高夹层纳米板的效率和能量容量。为捕捉尺寸效应，提出了具有两个尺寸相关因子的非局部应变-应力梯度理论。横向剪切变形因子在预测各种结构的机械性能方面具有重要作用。因此，在当前工作中，研究了一种新的四变量精炼准三维对数剪切变形理论。同时，针对压电贴片与复合结构的耦合，提出了相容性条件。为获得 NEMS 的耦合控制方程，提出了具有三个因子的汉密尔顿原理。为了求解当前电气系统的偏微分方程，介绍了一种分析求解程序。此外，为了更好地了解当前电气系统的基频，还介绍了 COMSOL 三物理仿真。为了验证结果，介绍了一种通过数学和 COMSOL 多物理场仿真数据集的人工智能工具，以较低的计算成本验证其他输入数据的结果。最后，详细讨论了压电贴片的几何形状、FG 功率指数、长度比例因子、非局部参数和压电贴片位置等各种因素对相位速度的影响。当前工作的重要成果之一是，设计人员在建立 NEMS 模型时应注意施加电压、压电贴片的位置和几何形状。

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引用次数: 0

Study on the transition mechanism of vibrating low-pressure turbine blades based on large Eddy simulation 基于大涡流模拟的低压涡轮叶片振动过渡机制研究

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-26 DOI: 10.1016/j.ast.2024.109695

Zhang Yingqiang , Dong Xu , Wu Xuan , Zhang Yanfeng , LU Xingen , ZHU Junqiang

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 (Re = 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.

低压涡轮叶片由于轮廓薄、长宽比大，很容易出现振动问题。叶片振动会严重影响边界层的演变和流动状态。本文利用大涡模拟来预测低压涡轮叶片吸入侧边界层在低雷诺数（Re = 25,000）下的发展。它引入了不同的振动情况，以阐明叶片振动影响边界层分离和过渡的机制。研究表明，振动情况的引入大大减小了整体跨向涡流的大小及其卷起高度。在振动叶片的后缘附近，可以观察到交错分布的跨向涡流，其特点是高低区域交替出现。较短的跨度涡迅速发展，几乎穿越了发夹涡（Λ涡）的产生和发展过程，并直接分解为较小尺度的涡。这加速了过渡过程。叶片振动主要是通过促进分离剪切层内 K-H 不稳定机制主导的过渡过程来促进湍流重新附着。因此，它能有效限制叶片吸入侧分离气泡的增长，从而显著降低气动损失。此外，在一定范围内提高振动频率可以放大这些效果，与静止叶片相比，总压力损失最多可减少 23%。

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引用次数: 0

Research on the flutter characteristics of folding wings with variable swept angles of the outer wing 外翼可变后掠角折叠翼的扑翼特性研究

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-24 DOI: 10.1016/j.ast.2024.109685

Jin-Gang Wang, Xiang-Ying Guo

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.

针对基于传统设计的可变机翼配置，对折叠翼飞机的临界扑翼速度以及相关稳定性和安全性进行了评估。通过理论分析和数值模拟验证，详细研究了铰链刚度、后掠角和折叠角等参数对折叠翼扑翼和稳定性的影响。结果表明，在指定的安全铰链刚度下，所提出的可变扫掠折叠翼构型可以提高危险折叠角下的临界扑翼速度。通过联合操纵折叠角和扫掠角，折叠翼的气动阻力得以降低，从而提高了其飞行速度和扑翼边界。本文旨在为变翼构型的设计和稳定性分析提供新的见解。

引用次数: 0

Point-enhanced convolutional neural network: A novel deep learning method for transonic wall-bounded flows 点增强卷积神经网络：用于跨音速壁面流的新型深度学习方法

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-23 DOI: 10.1016/j.ast.2024.109689

Fernando Tejero, Sanjeeth Sureshbabu, Luca Boscagli, David MacManus

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 (

M_{i s}

), pre-shock isentropic Mach number and shock location (

X / L_{n a c}

) are captured within

Δ M_{i s}

= 0.02,

Δ M_{i s} = 0.04

,

Δ X / L_{n a c} = 0.007

, 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.

低阶模型可用于加速工程设计流程。理想情况下，这些代用模型应满足设计空间覆盖面大、精度高和评估速度快等相互冲突的要求。在跨音速条件下的航空航天应用中，由于相关流动机制的非线性，这可能具有挑战性。过去曾研究过不同的方法来预测翼面或圆柱体等形状周围的流场。然而，这些方法通常空间分辨率较低，限制了对跨音速壁面流感兴趣的边界层内的预测能力。本研究提出了一种新颖的点增强卷积神经网络（PCNN）方法，该方法结合了成熟的点网络和卷积神经网络方法的优点。PCNN 模型在训练过程中对内存的要求相对较低，保留了域中的空间相关性，并具有与传统计算方法相同的分辨率。该结构被用于民用航空发动机短舱的流场预测，结果表明峰值等熵马赫数（Mis）、冲击前等熵马赫数和冲击位置（X/Lnac）等流动特征分别在 ΔMis = 0.02、ΔMis=0.04、ΔX/Lnac=0.007 的范围内被捕获。PCNN 模型成功地预测了边界层的积分参数，其中不可压缩位移厚度、动量厚度和形状系数通常在 CFD 预测值的 5%以内。总之，PCNN 方法在包括冲击波和冲击诱导分离在内的一系列流动物理条件下的跨音速壁面流动中得到了验证。

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引用次数: 0

Active maneuver load alleviation for a pitching wing via spanwise-distributed camber morphing 通过跨度分布式外倾角变形减轻俯仰翼的主动机动载荷

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-23 DOI: 10.1016/j.ast.2024.109693

You Wu , Jinying Li , Yuting Dai , Yongchang Li , Chao Yang

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%.

本文介绍了一种非线性模型反演（NMI）控制器的设计与验证，该控制器用于减轻基于跨度分布式主动外倾变形的俯仰摆动翼的机动载荷。利用递归神经网络（RNN）预测机翼大振幅俯仰机动引起的非线性和非稳定气动力，并引入全连接神经网络建立气动弹性系统的动态反演，以进行控制律设计。反演后的系统与 PI 控制器连接，形成一个非线性有源控制器。该控制器首先在离线环境下用于带有跨度分布式主动外倾角变形的 1DoF 俯仰有限跨度机翼，然后在基于 CFD 的流体-结构-控制耦合仿真中进行验证。结果表明，离线控制器可以消除操纵载荷。在基于 CFD 的流固耦合仿真中，弯矩可减少 38%。

引用次数: 0

Efficient fuzzy simulations for estimating the failure credibility of engineering structures under fuzzy environment 模糊环境下估算工程结构失效可信度的高效模糊模拟

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-22 DOI: 10.1016/j.ast.2024.109688

Yujie Gu , Menghao Xue , Yunwen Miao , Mingxuan Zhao , Qing Ma

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.

在模糊环境下，高效、准确地求解结构系统的失效可信度在工程领域发挥着重要作用。更精确的失效可信度有助于评估系统的安全程度，进而减少安全事故的发生。目前，扩展模糊一阶二瞬法（EFFOSM）在某些场合能有效地分析失效可信度。然而，当涉及复杂的性能函数和模糊输入时，EFFOSM 的准确性会大大降低，其效率也有待提高。为克服上述不足，本文提出了两种新型模糊仿真算法，即均匀离散化算法（UDA）和分段仿真算法（BSA）。对于涉及经常遇到的连续和严格单调性能函数的规则 LR 模糊区间输入的系统，这两种算法能以更高的效率和精度估计故障可信度。随后，借助 EFFOSM 中的线性化和正则化程序，UDA 和 BSA 的应用扩展到不规则 LR 模糊区间的非单调性能函数。为了评估和验证所提出的两种算法的性能，我们通过一些数值示例和实际问题将它们与 EFFOSM 进行了比较。结果表明，所提出的两种算法在精度和效率方面均优于 EFFOSM，而且在估计涉及规则 LR 模糊区间输入的严格单调性能函数的故障可信度方面具有更广泛的应用范围。同时，在运行时间较短方面，BSA 略优于 UDA。

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引用次数: 0

Additively-manufactured shear tri-coaxial rocket injector mixing and combustion characteristics 添加式制造的剪切三轴火箭喷射器的混合和燃烧特性

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-22 DOI: 10.1016/j.ast.2024.109680

Alex R. Keller , Fabio A. Bendana , Vincent C. Phong , R. Mitchell Spearrin

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.

利用增材制造技术实现了一种整体式三同轴推进剂喷射方案，以增强液体推进剂火箭系统中甲烷与氧气的混合。利用激光吸收层析成像和化学发光成像技术，在 1-69 巴范围内对三轴向设计的混合和燃烧特性进行了实验评估，并与传统制造的双轴设计进行了比较。通过激光吸收光谱方法生成了温度和一氧化碳分子分数的定量二维图像，而 OH* 化学发光则为定义火焰长度和喷射器间距的燃烧热释放提供了近似度量。在压力和氧化剂与燃料比率相似的情况下，三轴向喷射器设计可增强混合和燃烧过程，减少特征混合长度尺度，并实现相对于更传统的双轴设计的更佳燃烧性能。尽管混合得到了加强，但三同轴设计在减少火焰与喷射器面的距离方面表现得更为有限，这表明可以控制喷射器面增加的热通量。三轴向喷射器凸显了利用增材制造提高性能和简化液体推进剂火箭发动机制造的潜力。

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引用次数: 0

Nonlinear dynamic characteristics of smart FG-GPLRC sandwich varying thickness truncated conical shell with internal resonance for first three order modes 智能 FG-GPLRC 夹层变厚截顶锥形壳体的非线性动态特性，前三阶模式的内部共振

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-22 DOI: 10.1016/j.ast.2024.109672

Shaowu Yang , Zhiquan Wang , Yuxin Hao , Wei Zhang , Yan Niu , Wensai Ma

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.

本文研究了在横向载荷和平面内力的共同作用下，简支变厚功能分级石墨烯平板增强复合材料（FG-GPLRC）智能截顶夹层锥壳的 1:1:1 内部共振非线性动力特性。截断式智能夹层锥形壳由一个不同厚度的 FG-GPLRC 核心层和两个磁电弹性面层组成，其材料属性和构成关系分别由混合规则、改进的 Halpin-Tsai 方法和广义胡克定律确定。利用一阶剪切变形理论（FSDT）、von Karman 几何非线性、汉密尔顿原理和 Galerkin 技术，建立了截顶智能 FG-GPLRC 锥壳的 3DOF 无量纲非线性动力学公式。应用多尺度技术建立了截顶智能 FG-GPLRC 锥壳在组合共振下的平均方程。非线性方程求解器和 Runge-Kutta 方法可以描绘出频率响应和力响应曲线、Poincare 图、相位图、时间历程图、分岔图和最大 Lyapunov 指数图。研究了阻尼和调谐参数、横向力和面内力对截断智能变厚 FG-GPLRC 夹层锥壳 1:1:1 内部共振非线性动态特性的影响。

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引用次数: 0