Engineering Analysis with Boundary Elements最新文献_第10页

Transformer-based flexible sampling ratio compressed ghost imaging 基于变压器的柔性采样比压缩虚影成像

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2025-01-01 DOI: 10.1016/j.enganabound.2024.106050

Jiayuan Liang, Yu Cheng, Jiafeng He

Recently, deep learning has been tried to improve the efficiency of compressed ghost imaging. However, these current learning-based ghost imaging methods have to modify and retrain the learning model to cope with different sampling ratios. This will consume a lot of computing resources and energy. In this paper, we propose a deep learning-based compressed ghost imaging method that can adapt to arbitrary sampling ratios without tailoring and retraining model. By simultaneously optimizing the weights of both the speckle patterns and the transformer model, we achieve a network for ghost imaging at arbitrary sampling ratios. The feasibility and effectiveness of the proposed method were validated through numerical simulations. The results indicate that the proposed method, requiring only a single training session, is capable of reconstructing high-quality images under varying sampling ratios. Furthermore, the performance of the proposed method surpasses that of currently widely employed deep learning ghost imaging methods. At a sampling ratio of 5%, the proposed method achieves an increase of 1.87 dB in Peak Signal-to-Noise Ratio (PSNR) and 0.171 in Structural Similarity Index (SSIM).

近年来，深度学习被用于提高压缩鬼影成像的效率。然而，目前这些基于学习的鬼影成像方法必须修改和重新训练学习模型以应对不同的采样比。这将消耗大量的计算资源和能源。在本文中，我们提出了一种基于深度学习的压缩鬼影成像方法，该方法可以适应任意采样比，无需裁剪和再训练模型。通过同时优化散斑模式和变压器模型的权重，我们实现了任意采样比下的鬼影成像网络。通过数值仿真验证了该方法的可行性和有效性。结果表明，该方法只需要一次训练，就能在不同采样比下重建出高质量的图像。此外，该方法的性能优于目前广泛使用的深度学习鬼影成像方法。在5%的采样比下，该方法的峰值信噪比（PSNR）和结构相似指数（SSIM）分别提高了1.87 dB和0.171 dB。

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引用次数: 0

An efficient coupled fluid flow-geomechanics model for capturing the dynamic behavior of fracture systems in tight porous media 一种有效的流体流动-地质力学耦合模型，用于捕获致密多孔介质中裂缝系统的动态行为

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-29 DOI: 10.1016/j.enganabound.2024.106046

Xulin Du , Linsong Cheng , Maojun Fang , Xiang Rao , Sidong Fang , Renyi Cao

This paper introduces an efficient hybrid numerical discretization method designed to address the coupled mechanical challenges of geomechanics and fluid flow during pressure depletion in tight reservoirs. Utilizing the extended finite element method, this approach solves the elastic deformation of rock, while the mixed boundary element method precisely calculates the unsteady fluid exchange between the matrix and fractures. These numerical schemes are integrated fully, with temporal dynamics managed through a fully implicit method that effectively characterizes fracture deformation and fluid flow in hydrocarbon development. Furthermore, this model incorporates embedded pre-treatment to represent hydraulic macro-fractures and considers the effects of proppant. It captures dynamic information regarding the matrix and minor natural fractures through the double-porosity effective stress principle and a dual-medium implicit fracture characterization method. Thus, the proposed hybrid model provides a comprehensive depiction of the complex interplay between the matrix, natural fractures, and hydraulic fractures. The model's accuracy is validated through various examples, highlighting its reliability. This research offers valuable theoretical insights for advancing the development of unconventional hydrocarbon resources.

本文介绍了一种有效的混合数值离散化方法，旨在解决致密储层压力耗尽过程中地质力学和流体流动的耦合力学挑战。该方法利用扩展有限元法求解岩石的弹性变形，而混合边界元法则精确计算基质与裂缝之间的非定常流体交换。这些数值格式完全集成，并通过完全隐式方法管理时间动力学，有效表征油气开发过程中的裂缝变形和流体流动。此外，该模型还考虑了支撑剂的影响，采用了嵌入的预处理方法来表示水力宏观裂缝。该方法通过双孔隙度有效应力原理和双介质隐式裂缝表征方法获取基质和天然小裂缝的动态信息。因此，所提出的混合模型提供了基质、天然裂缝和水力裂缝之间复杂相互作用的综合描述。通过实例验证了模型的准确性，突出了模型的可靠性。该研究为推进非常规油气资源开发提供了有价值的理论见解。

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引用次数: 0

An improved weakly compressible SPH method for simulating 2D multiphase flows with complex interface and large density ratios 用于模拟具有复杂界面和大密度比的二维多相流的改进型弱可压缩 SPH 方法

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-26 DOI: 10.1016/j.enganabound.2024.106043

Xiaoyang Xu , Erdi Wang , Xiang Li , Peng Yu

This paper develops an improved weakly compressible smoothed particle hydrodynamics (SPH) method for simulating multiphase flows with complex interface and large density ratios. Surface tension is computed using a continuum surface force method along with a kernel gradient correction algorithm, thereby improving the numerical precision of normal vectors and curvatures. To maintain a uniform particle distribution and prevent instabilities resulting from particle stretching, a particle shifting technique is implemented. Additionally, an anisotropic interfacial repulsion force is introduced at the multiphase interface to create smooth phase boundaries and mitigate issues related to particle penetration. The efficacy of the method is demonstrated through simulations of various scenarios including the deformation of a square droplet, the Rayleigh-Taylor instability, the lock-exchange phenomena, a single rising bubble, and two rising bubbles. By comparing the results with analytical solutions and existing literature data, the accuracy and consistency of the numerical results are confirmed. These comparisons demonstrate that the improved multiphase SPH method developed in this study can effectively track deformable phase interfaces and simulate multiphase flows with complex interfaces and large density ratios in a stable way.

本文开发了一种改进的弱可压缩平滑粒子流体力学（SPH）方法，用于模拟具有复杂界面和大密度比的多相流。表面张力的计算采用连续表面力法和核梯度修正算法，从而提高了法向量和曲率的数值精度。为了保持颗粒分布均匀，防止颗粒拉伸造成不稳定，采用了颗粒移动技术。此外，还在多相界面上引入了各向异性的界面斥力，以创建平滑的相界并缓解与粒子穿透有关的问题。通过模拟各种情况，包括方形液滴的变形、瑞利-泰勒不稳定性、锁定交换现象、单个上升气泡和两个上升气泡，证明了该方法的有效性。通过将结果与分析解和现有文献数据进行比较，证实了数值结果的准确性和一致性。这些比较结果表明，本研究开发的改进型多相 SPH 方法可以有效地跟踪可变形的相界面，稳定地模拟具有复杂界面和大密度比的多相流。

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引用次数: 0

Rockburst proneness analysis of rock materials based on the discrete element method 基于离散元法的岩石材料岩爆易发性分析

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-22 DOI: 10.1016/j.enganabound.2024.106047

Yunhe Ao , Baoxin Jia , Chuang Sun , Dongxu Chen , Yunbo Pu

To explore the rockburst proneness of rock materials, coarse-grained granite, red sandstone and white marble were selected for uniaxial compression laboratory tests. Applying the rockburst proneness criterion based on the peak strength strain storage index, numerical models of the three rocks were constructed according to the three-dimensional Clump (3D-Clump) modelling method using the three-dimensional Particle Flow Code (PFC3D) in the Discrete Element Method (DEM). Numerical simulations of conventional uniaxial compression (UC) and single cyclic loading-unloading uniaxial compression (SCLUC) tests were carried out to estimate the rockburst proneness of the three rocks. The results show that the 3D-Clump model can match different types of rock materials by setting the proper clump radius and meso parameters. The stress-strain curves in the UC numerical simulation tests of the three rocks are very similar to those of laboratory tests. In the SCLUC numerical simulation tests, the peak strengths of the three rocks at different unloading stress levels k do not differ by more than 5 % from that of the conventional UC tests. Based on the rockburst proneness criterion of the peak strength strain storage index, combined with the final fracture modes in the SCLUC tests, it is concluded that coarse-grained granite has high rockburst proneness, and red sandstone and white marble have low rockburst proneness.

为了探究岩石材料的岩爆性，选择了粗粒花岗岩、红砂岩和白色大理岩进行单轴压缩实验室试验。根据基于峰值强度应变存储指数的岩爆标准，使用离散元法（DEM）中的三维粒子流代码（PFC3D），按照三维岩块（3D-Clump）建模方法构建了这三种岩石的数值模型。对常规单轴压缩（UC）和单次循环加载-卸载单轴压缩（SCLUC）试验进行了数值模拟，以估算这三种岩石的易爆性。结果表明，通过设置适当的岩块半径和中间参数，三维岩块模型可以匹配不同类型的岩石材料。三种岩石在 UC 数值模拟试验中的应力-应变曲线与实验室试验的应力-应变曲线非常相似。在 SCLUC 数值模拟试验中，三种岩石在不同卸荷应力水平 k 下的峰值强度与传统 UC 试验的峰值强度相差不超过 5%。根据峰值强度应变存储指数的易爆性标准，结合 SCLUC 试验的最终断裂模式，可以得出结论：粗粒花岗岩的易爆性较高，红砂岩和白色大理岩的易爆性较低。

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引用次数: 0

Simulation analysis of detonation wave propagation in explosive with multiple initiation points by generalized Interpolation material point method 用广义插值材料点法模拟分析多起爆点炸药中的爆轰波传播

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-21 DOI: 10.1016/j.enganabound.2024.106044

Cheng Yu , Xiaojie Li , Honghao Yan , Xiaohong Wang , Yuxin Wang

In the research of explosion shock theory and engineering application, the convergence of detonation waves can be realized by using multiple initiation points to utilize the detonation energy and pressure effectively. To study the propagation process of detonation wave and the distribution law of impact energy of the explosive with multiple initiation points, a detonation calculation model of the explosive with multiple initiation points is constructed using an improved material point method, namely the generalized interpolation material point (GIMP) method. Meanwhile, two-dimensional and three-dimensional numerical simulations are given on detonation wave propagation and convergence processes in explosives with multiple initiation points. The process of detonation wave formation and convergence is simulated by Wuji Particle Dynamics (WP-DYNA) software, and the dynamic changes of physical parameters such as detonation pressure, product density, and internal energy are analyzed in detail. To verify the accuracy of numerical simulation, corresponding explosive detonation experiments are carried out; the simulation results are compared with the ultra-high speed photoelectric framing photography and the aluminum ingot double detonating cord experiment. The results show that the generalized interpolation material point method has good stability and relatively high calculation accuracy when simulating explosive detonation waves. A robust numerical calculation tool can be provided for the practical application of explosive detonation.

在爆炸冲击理论和工程应用研究中，利用多起爆点可以实现爆轰波的收敛，有效利用爆轰能量和压力。为研究多起爆点炸药的起爆波传播过程和冲击能量分布规律，采用改进的材料点法，即广义插值材料点法（GIMP），构建了多起爆点炸药的起爆计算模型。同时，对多起爆点炸药的起爆波传播和收敛过程进行了二维和三维数值模拟。利用无极粒子动力学（WP-DYNA）软件模拟了起爆波的形成和收敛过程，并详细分析了起爆压力、产品密度和内能等物理参数的动态变化。为验证数值模拟的准确性，进行了相应的炸药起爆实验，并将模拟结果与超高速光电取景摄影和铝锭双导爆索实验进行了对比。结果表明，广义插值材料点法在模拟爆炸起爆波时具有良好的稳定性和较高的计算精度。为爆炸起爆的实际应用提供了可靠的数值计算工具。

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引用次数: 0

A fast calculation method for dynamic topology optimization based on hybrid spectral element method 基于混合谱元法的动态拓扑优化快速计算方法

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-21 DOI: 10.1016/j.enganabound.2024.106049

Enying Li , Jiakang Niu , Hu Wang

In this study, a Hybrid Spectral Element Method (HSEM) integrated with Equivalent Static Load (ESL) in the frequency domain is suggested. This integration aims to enhance the computational efficiency of dynamic topology optimization. In comparison with existing techniques, the proposed HSEM transforms the governing equation of dynamic analysis into a spectral element equation within the frequency domain by utilizing the Fast Fourier Transform (FFT) algorithm. This approach enables the representation of both structural displacements and external loads in spectral forms, potentially leading to a reduction in the number of dimensions compared to traditional time-interval-based methods. By using spectral representation, a low-dimensional ESL set can be constructed in the frequency domain for model reduction. To validate the effectiveness of the suggested proposed method, extensive analyses and comparisons using various two-dimensional (2D) and three-dimensional (3D) examples are carried out. The obtained results demonstrate a substantial improvement in computational efficiency, both during the dynamic analysis phase and the quasi-static topology optimization phase, while maintaining high levels of accuracy. Moreover, even as the scale of the model increases, our method maintains its advantage in computational efficiency. In the test examples, a maximum speedup ratio of up to 6.54 times was observed, indicating the significant potential of the proposed HSEM-ESL approach in enhancing the performance of dynamic topology optimization tasks.

本研究提出了一种在频域与等效静载荷 (ESL) 相结合的混合谱元法 (HSEM)。这种集成旨在提高动态拓扑优化的计算效率。与现有技术相比，拟议的 HSEM 利用快速傅立叶变换 (FFT) 算法将动态分析的控制方程转换为频域内的谱元方程。这种方法能以频谱形式表示结构位移和外部载荷，与传统的基于时间间隔的方法相比，有可能减少维数。通过使用频谱表示法，可以在频域中构建低维 ESL 集，从而减少模型。为了验证所建议方法的有效性，我们使用各种二维（2D）和三维（3D）实例进行了广泛的分析和比较。结果表明，无论是在动态分析阶段还是在准静态拓扑优化阶段，计算效率都得到了大幅提高，同时还保持了较高的精度。此外，即使模型的规模增大，我们的方法仍能保持其在计算效率方面的优势。在测试实例中，观察到的最大加速比高达 6.54 倍，这表明所提出的 HSEM-ESL 方法在提高动态拓扑优化任务性能方面具有巨大潜力。

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引用次数: 0

Study on direct shear mechanical characteristics of grouted-filled jointed coal using discrete element method 利用离散元素法研究灌浆填充节理煤的直接剪切力学特性

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-20 DOI: 10.1016/j.enganabound.2024.106048

Xuewei Liu , Weilong Tao , Bin Liu , Sai Wang , Wei Deng , Ying Fan

Grouting is a widely used technique in underground engineering by enhancing mechanical properties of jointed rock mass. Understanding the shear characteristics of jointed coal mass after grouting reinforcement is crucial for optimizing grouting parameters and advancing grouting mechanism. This study proposed a grout-filled jointed coal (GJC) direct shear discrete element model (GJCS-DEM). The model consists of coal matrix, grout-filled layer, and coal-grout interface. Parallel bond model (PBM) was adopted on intact coal matrix and grout-filled layer, while smooth joint model (SJM) was utilized to model deform behavior of interface in this model. Then, microscopic parameters determination method for SJM in GJCS-DEM has also been introduced and all the parameters for PBM and SJM were calibrated. After that, the proposed approach was validated through the good agreement between strength and failure characteristics of numerical and experimental direct shear test results of specimens with different grouting materials. Finally, the validated GJCS-DEM was applied to investigate effect factors of shear mechanical propertied for GJC specimens. As the grout-filled layer height and joint sawtooth dig angle increases, both peak and residual strength increases, while the failure pattern varies. The work here can offer valuable insights for grouting efficiency improvement in engineering practices.

灌浆是地下工程中广泛使用的一种技术，它可以提高节理岩体的机械性能。了解灌浆加固后节理煤块的剪切特性对于优化灌浆参数和推进灌浆机制至关重要。本研究提出了一种灌浆填充节理煤（GJC）直接剪切离散元模型（GJCS-DEM）。该模型由煤基体、灌浆填充层和煤-灌浆界面组成。在该模型中，完整的煤基体和灌浆层采用平行粘结模型（PBM），界面的变形行为采用光滑接缝模型（SJM）。然后，还介绍了 GJCS-DEM 中 SJM 的微观参数确定方法，并校准了 PBM 和 SJM 的所有参数。之后，通过不同灌浆材料试样的直接剪切试验结果，验证了所提出的方法在强度和破坏特征方面与数值试验结果的良好一致性。最后，将经过验证的 GJCS-DEM 应用于研究 GJC 试件的剪切力学性能影响因素。随着灌浆层高度和连接锯齿挖角的增加，峰值强度和残余强度都会增加，而破坏模式则各不相同。这项工作可为工程实践中提高灌浆效率提供有价值的见解。

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引用次数: 0

Numerical study on the damage of floating ice by high-pressure bubble loads 高压气泡载荷对浮冰破坏的数值研究

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-19 DOI: 10.1016/j.enganabound.2024.106041

Qigang Wu , Chenxi Zhang , Bao-Yu Ni , Zerui Yu , Di Yang , Yanzhuo Xue

Floating ice can be damaged by the bubble loads generated by releasing high-pressure gas underwater using an air-gun, so ice-breaking by underwater high-pressure bubble loads is becoming one of the effective ice-breaking technologies. A numerical model was established to study the motion and damage of floating ice subjected to high-pressure bubble loads. Empirical formulas were used to calculate the initial shock wave load. The boundary element method (BEM) was used to simulate the bubble motion and second shock wave load/jet impact load of the underwater bubble under the ice plate, during which the Green's formula was used. The potential flow theory was used to solve kinematic and dynamic problems during the bubble motion process. A breakable floating ice plate was established based on peridynamics (PD). A coupling scheme was proposed to solve the load transfer problem between BEM and PD. The numerical results of the bubble motion stage and the ice-breaking stage were in good agreement with the literature results. The motion response of floating ice was obtained and analyzed. Focusing on studying the damage process of the floating ice, the influence of bubble initial internal pressure and ice mechanical parameters (Young's modulus) were studied. Results showed that the dimensionless distance parameter H, dimensionless ice thickness parameter T, and ice mechanical parameters cause significant effect on ice damage. This study provided a numerical model for ice-breaking by high-pressure bubble loads, which may provide reference for parameter optimization design and help to guide the engineering application.

利用气枪在水下释放高压气体产生的气泡载荷可以破坏浮冰，因此利用水下高压气泡载荷破冰正在成为有效的破冰技术之一。为研究浮冰在高压气泡载荷作用下的运动和破坏情况，建立了一个数值模型。利用经验公式计算了初始冲击波载荷。采用边界元法（BEM）模拟冰板下的气泡运动和水下气泡的第二次冲击波载荷/喷射冲击载荷，期间使用了格林公式。利用势流理论解决气泡运动过程中的运动学和动力学问题。基于周动力学（PD）建立了可破碎浮动冰板。提出了一种耦合方案来解决 BEM 和 PD 之间的载荷传递问题。气泡运动阶段和破冰阶段的数值结果与文献结果吻合良好。获得并分析了浮冰的运动响应。重点研究了浮冰的破坏过程，研究了气泡初始内压和冰力学参数（杨氏模量）的影响。结果表明，无量纲距离参数 H、无量纲冰厚参数 T 和冰力学参数对冰损伤有显著影响。该研究提供了高压气泡载荷破冰的数值模型，可为参数优化设计提供参考，有助于指导工程应用。

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引用次数: 0

Asymptotic homogenization for effective parameters of unidirectional fiber reinforced composites by isogeometric boundary element method 用等几何边界元法实现单向纤维增强复合材料有效参数的渐近同质化

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-18 DOI: 10.1016/j.enganabound.2024.106036

Zhilin Han , Shijia Liu , Yu Deng , Chuyang Luo

In this paper, formulations for asymptotic homogenization method based on the boundary element method (BEM) are presented for the estimations for effective parameters of unidirectional fiber reinforced composites in the 2D plane strain case. The boundaries are discretized by shape functions of non-uniform rational B-splines (NURBS) according to the features of isogeometric analysis and the related isogeometric boundary element method is established. The strongly and weakly singular integrals in the boundary integral equations are precisely calculated in direct schemes. Comprehensive comparisons for the obtained effective parameters by the current method are conducted with the existing ones by conventional BEM and the ones by finite element method (FEM). It is found that the estimations in present work are more accurate than the ones by conventional BEM with fewer control points and are also more accurate than the ones by FEM for fibers with more complex geometry. The outperformance of the current method shows competitive potentials in homogenization for the real 3D composites.

本文提出了基于边界元法（BEM）的渐近均质化方法公式，用于估算二维平面应变情况下单向纤维增强复合材料的有效参数。根据等几何分析的特点，采用非均匀有理 B-样条曲线（NURBS）的形状函数对边界进行离散化，并建立了相关的等几何边界元方法。边界积分方程中的强奇异积分和弱奇异积分在直接方案中得到精确计算。将当前方法获得的有效参数与传统 BEM 和有限元法（FEM）获得的有效参数进行了综合比较。结果发现，在控制点较少的情况下，本研究的估算结果比传统 BEM 方法更为精确，而对于几何形状更为复杂的纤维，本研究的估算结果也比 FEM 方法更为精确。当前方法的优越性能显示了其在实际三维复合材料均质化方面的竞争潜力。

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引用次数: 0

Optimally shaped nanotubes for field concentration 用于场强集中的最佳形状纳米管

IF 4.2 2区工程技术 Q1 ENGINEERING, MULTIDISCIPLINARY

Engineering Analysis with Boundary Elements

Pub Date : 2024-11-16 DOI: 10.1016/j.enganabound.2024.106022

Konstantinos V. Kostas , Constantinos Valagiannopoulos

The problem of concentrating electromagnetic fields into a nanotube from an ambient source of light, is considered. An isogeometric analysis approach, in a boundary element method setting, is employed to evaluate the local electric field, which is represented with the exact same basis functions used in the geometric representation of the nanotube. Subsequently, shape optimization of the nanotubes is performed with the aim of maximizing the field concentration in their interior. The optimization framework comprises: (i) one global optimizer implemented as the combination of a derivative-free guided random search approach and a gradient-based algorithm for accurately determining the shape at the final stages, (ii) one parametric modeler generating valid non-self-intersecting nanotube shapes with a relatively small number of parameters, and (iii) one isogeometric-enabled boundary element method solver approximating the value of the electric field on the nanotube with high accuracy. The optimal shapes for a wide range of optical sizes are determined, resulting in a collected energy enhancement of more than two orders of magnitude, compared to the respective circular designs. Importantly, the frequency and angular responses of selected optimal shapes tend to maintain their superior performance over extensive wavelength and directional bands. Therefore, the presented results may assist substantially the photonic inverse design in nanotube-based setups with applications spanning from field localization and power accumulation to wave steering and energy harvesting.

研究考虑了从环境光源向纳米管集中电磁场的问题。在边界元方法设置中，采用等几何分析方法来评估局部电场，该方法使用与纳米管几何表示法完全相同的基函数来表示局部电场。随后，对纳米管的形状进行优化，目的是使其内部的电场浓度最大化。优化框架包括：(i) 结合无导数引导随机搜索方法和基于梯度的算法实现的全局优化器，用于在最后阶段精确确定形状；(ii) 参数建模器，以相对较少的参数生成有效的非自相交纳米管形状；(iii) 支持等几何的边界元素法求解器，高精度地近似纳米管上的电场值。确定了适用于各种光学尺寸的最佳形状，与相应的圆形设计相比，收集的能量提高了两个数量级以上。重要的是，所选最佳形状的频率和角度响应往往能在广泛的波长和方向频段内保持其卓越性能。因此，本文介绍的结果可能对基于纳米管的光子反向设计有很大帮助，其应用范围包括场定位、功率积累、波转向和能量收集。

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引用次数: 0