Aerospace Science and Technology最新文献_第6页

Sound generated by the interaction between shock and instability waves in supersonic round jets 超音速圆射流中激波与不稳定波相互作用产生的声音

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-17 DOI: 10.1016/j.ast.2026.111692

Binhong Li , Benshuai Lyu

In this paper, we develop an analytical model to investigate the sound generated by the shock-instability interactions (SII) in supersonic round jets, extending our previous two-dimensional planar study to circular configurations. The jet is represented by a vortex sheet, with its motion modeled by the Euler equations. Shock and instability waves are modeled using Pack’s approach and the linear stability theory, respectively, while their interaction is calculated by solving an inhomogeneous wave equation. Using the Fourier transform and steepest descent method, we obtain a closed-form solution for the resulting acoustic field. Results due to the interaction between the instability waves and one interaction cell capture the key directivity features of screech reported in experiments and numerical simulations, indicating that the classic monopole assumption may be inadequate. In particular, the screech-tone intensity due to multiple shock cells decays rapidly as the observer angle approaches 180 degrees, which is in better agreement with the experimental data measured by Norum. We further analyze how the instability wave growth rate influences these directivity patterns and examine the sound generation efficiency of the broadband shock-associated noise. Finally, an examination of near-field pressure fluctuations due to the SII reveals that noise is produced primarily via the Mach wave radiation mechanism.

在本文中，我们建立了一个分析模型来研究超音速圆形射流中冲击-不稳定相互作用（SII）产生的声音，将我们之前的二维平面研究扩展到圆形构型。射流用旋涡片表示，其运动由欧拉方程模拟。激波和不稳定波分别使用Pack方法和线性稳定性理论建模，而它们的相互作用通过求解非齐次波动方程来计算。利用傅里叶变换和最陡下降法，我们得到了声场的封闭解。由于不稳定波和一个相互作用单元之间的相互作用，结果捕获了实验和数值模拟中报道的尖叫的关键指向性特征，表明经典的单极子假设可能是不充分的。特别是，当观察者角度接近180度时，多个激波细胞产生的尖音强度衰减迅速，这与Norum测量的实验数据更吻合。我们进一步分析了不稳定波增长速率如何影响这些指向性模式，并检查了宽带冲击相关噪声的声产生效率。最后，对SII引起的近场压力波动的研究表明，噪声主要是通过马赫波辐射机制产生的。

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引用次数: 0

Classification of unstart flow in a two-dimensional hypersonic inlet 二维高超声速进气道未启动流的分类

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-17 DOI: 10.1016/j.ast.2026.111678

Nannan Wang , Guoqing Zhang , S.C.M. Yu

In this paper, attempts have been made to the classification of hard unstart flow in a two-dimensional hypersonic inlet based on the characteristics of mass flow capture ratio vs freestream Mach number and the corresponding flow field structures obtained by numerical simulations. It is found that hard unstart can be broadly classified into four categories: 1) cowl angle unstart (CAU), 2) upper separation unstart (USU), 3) throat compression unstart (TCU), and 4) throat expansion unstart (TEU). As the internal contraction ratio (ICR) increases, the mass flow capture ratio for CAU remains constant because the disturbance from throat is blocked by a fully supersonic region. USU can be regarded approximately as a special form of CAU with the influence from the separation bubble at upper wall. TEU is equivalent to introducing throat expansion wave effect to CAU by reducing ICR. TCU is dominated by throat high pressure with a large subsonic region at bottom wall as a medium for the pressure signal propagation. Different unstart categories exhibit distinct geometric sensitivities, with a particularly pronounced difference observed between CAU and TCU. Under large cowl angle, it is found that two novel flow regimes, namely the degenerated TCU and the quasi CAU, may arise due to system bifurcation. Finally, based on appropriate assumptions, empirical formulas for predicting the boundaries between different unstart categories are constructed. The prediction agrees well with the simulation results.

本文尝试基于质量流捕获比与自由流马赫数的特性以及数值模拟得到的相应流场结构，对二维高超声速进气道硬起动流动进行分类。发现硬起动大致可分为四类：1)罩角起动（CAU）， 2)上部分离起动（USU）， 3)喉部压缩起动（TCU）， 4)喉部膨胀起动（TEU）。随着内收缩比（ICR）的增加，由于来自喉部的干扰被全超音速区域阻挡，CAU的质量流捕获比保持不变。USU可以近似地看作是受上壁分离泡影响的CAU的一种特殊形式。TEU相当于通过降低ICR将喉部膨胀波效应引入CAU。TCU以喉部高压为主，底部壁面有较大的亚音速区域作为压力信号传播的介质。不同的unstart类别表现出不同的几何敏感性，CAU和TCU之间的差异尤为明显。在大冷却角下，由于系统分岔，可以产生两种新的流型，即退化TCU和准CAU。最后，在适当假设的基础上，构造了预测不同未启动类别之间边界的经验公式。预测结果与模拟结果吻合较好。

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引用次数: 0

Oscillation characteristics of the Mach disk and wall boundary flow on extremely underexpanded supersonic impinging jets 极欠膨胀超音速撞击射流马赫盘和壁面边界流动的振荡特性

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-17 DOI: 10.1016/j.ast.2026.111704

Qingmo Xie , Huakun Huang , Chun Lu , Peng Yu

Extremely underexpanded impinging jets, prevalent in scenarios like rocket launches and nuclear reactor leaks, exhibit complex flow dynamics with significant implications for structural impact and noise generation. This study examines the influence of nozzle pressure ratio (NPR) on the flow and oscillation characteristics of such jets using high-fidelity numerical simulations. Simulations reveal that increasing NPR (from 5 to 15) significantly weakens recirculation within the stagnation region, with suppression intensifying at higher NPRs. At NPR = 15, high-frequency oscillations, exceeding typical Mach disk frequencies, emerge in the stagnation region. Additionally, higher NPRs shift the peak wall friction force away from the impingement center, while reducing its amplitude and diminishing the contributions of boundary layer turbulence. However, turbulent kinetic energy increases with NPR, amplifying flow instability. Spectral Proper Orthogonal Decomposition and flow field reconstruction identify the dominant oscillation mechanism as a coupled interaction between the Mach disk and the wall jet, characterized by an oscillating wall jet driven by shock wave-boundary layer interactions. These findings elucidate the role of NPR in modulating jet dynamics and provide a theoretical foundation for assessing structural impacts and noise generation in high-pressure jet applications.

在火箭发射和核反应堆泄漏等场景中，极低膨胀的撞击射流表现出复杂的流动动力学，对结构冲击和噪声产生具有重要意义。本文采用高保真数值模拟方法研究了喷嘴压力比（NPR）对此类射流流动和振荡特性的影响。模拟结果表明，增加NPR（从5到15）会显著削弱停滞区内的再循环，在更高的NPR下抑制作用增强。在NPR = 15时，滞止区出现了超过典型马赫盘频率的高频振荡。此外，较高的npr使峰值壁面摩擦力远离撞击中心，同时减小了其振幅，减少了边界层湍流的贡献。然而，湍流动能随着NPR的增加而增加，加剧了流动的不稳定性。频谱固有正交分解和流场重建表明，主要振荡机制是马赫盘与壁面射流的耦合相互作用，其特征是激波与边界层相互作用驱动壁面射流振荡。这些发现阐明了NPR在调节射流动力学中的作用，并为评估高压射流应用中的结构影响和噪声产生提供了理论基础。

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引用次数: 0

Experimental and numerical study on the aerodynamic characteristics of a scissors rotor in vertical descent flight 剪刀旋翼垂直下降飞行气动特性的实验与数值研究

IF 5.6 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-17 DOI: 10.1016/j.ast.2026.111731

Chenkai Cao, Wangqing Zhu, Hongbo Gao, Guoqing Zhao, Qijun Zhao, Simeng Jing

引用次数: 0

Evaluation of a distributed fuelling scheme for a Mach 8 axisymmetric scramjet using large eddy simulation 基于大涡模拟的8马赫轴对称超燃冲压发动机分布式加油方案评价

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-17 DOI: 10.1016/j.ast.2026.111713

Sarah A. Mecklem, Damian Curran, Will O. Landsberg, Ananthanarayanan Veeraragavan

This paper examines supersonic turbulent combustion in an ethylene-fuelled Mach 8 axisymmetric scramjet using US3D with wall-modelled large eddy simulation (LES). A tandem cavity scramjet combustor with distributed fuelling was compared against a single cavity design with one fuelling location, which also served as a validation study. LES successfully replicated experimentally observed combustion and extended beyond the experimental test window to reveal the potential of domain unstart. Each LES was initialised from Reynolds-Averaged Navier-Stokes (RANS) solutions using turbulent Schmidt numbers (Sc_t) of either 0.3 or 0.75. While

S c_{t} = 0.30

produced a steady-state RANS solution matching experimental ‘steady’ pressure profiles, only the

S c_{t} = 0.75

LES captured the experimentally observed transient combustion behaviour resulting in domain unstart. These Sc_t-varied initialisations were applied to the tandem cavity domains which found the

S c_{t} = 0.3

domain produced robust scram-mode combustion, while

S c_{t} = 0.75

yielded marginal ignition behaviour. Combustion regime and Damköhler number analyses indicated that an ignition aid could enable the validated

S c_{t} = 0.75

condition to evolve and replicate the

S c_{t} = 0.3

case. LES demonstrated that distributed fuelling in tandem cavities can achieve stable, scram-mode combustion with reduced susceptibility to thermal choking and scramjet unstart. Although the ignition-supported LES predicted lower combustion efficiency (40%) than RANS (65%), the design’s distributed heat release supports improved flow stability and operational resilience.

本文利用US3D和壁面模拟大涡模拟（LES）研究了一架8马赫（ ）轴对称超燃冲压发动机的超声速湍流燃烧。将分布式加注的串联腔型超燃冲压发动机燃烧室与单一加注位置的单腔型设计进行了比较，作为验证研究。LES成功地复制了实验观察到的燃烧，并扩展到实验测试窗口之外，揭示了畴不启动的潜力。每个LES都是使用湍流施密特数（Sct） 0.3或0.75从reynolds - average Navier-Stokes （RANS）解初始化的。Sct=0.30产生了与实验“稳定”压力剖面相匹配的稳态RANS溶液，而只有Sct=0.75 LES捕获了实验观察到的瞬态燃烧行为，导致区域未启动。这些Sct变化的初始化应用于串联腔域，发现Sct=0.3域产生了强大的超燃模式燃烧，而Sct=0.75产生了边际点火行为。燃烧状态和Damköhler数值分析表明，助燃剂可以使验证的Sct=0.75条件演变并复制Sct=0.3的情况。LES试验表明，在串联腔内进行分布式加注可以实现稳定的超燃模式燃烧，同时降低了对热窒息和超燃发动机启动的敏感性。尽管点火支持的LES燃烧效率（40%）低于RANS(65%)，但该设计的分布式放热支持了更好的流动稳定性和运行弹性。

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引用次数: 0

Design and loss mechanisms analysis of supersonic turbine in turbopump application 超声速涡轮在涡轮泵应用中的设计及损失机理分析

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-17 DOI: 10.1016/j.ast.2026.111734

Xin Wei , Chen Yang , Hengtao Shi , Jinguang Yang

As the demand for high thrust-to-weight ratios in rocket engines increases, improving the performance of supersonic turbines in turbopumps has become a critical technical challenge. However, there is currently no effective methodology for designing the supersonic stator blade profile. To address this gap, the study proposes a novel supersonic stator design method based on the method of characteristics. This method generates expansion contours by solving the governing flow equations and integrating them into parameterized blade profiles. This enables efficient and precise generation of blade geometries that meet Mach number specifications and structural constraints. In a fuel turbopump case study, three-dimensional numerical simulations demonstrate that the designed supersonic stator provides circumferentially uniform flow to the rotor inlet, resulting in a 25 % increase in efficiency across the entire tip clearance range. Flow field analysis at the design point reveals that the stator design significantly reduces exit shock losses, with wake losses and endwall boundary layer friction losses as the dominant contributors. Additionally, tip leakage vortices and upper/lower passage vortices in the rotor occupy nearly the entire flow path at the turbine outlet, contributing to 76 % of total turbine losses. Off-design flow field analysis indicates that increasing rotational speed raises the critical pressure ratio, whereas reducing the pressure ratio amplifies adverse pressure gradients in the passage, significantly enlarging separation zones. The proposed parameterized supersonic stator design methodology enables the development of lightweight, high-performance turbopump turbines while providing valuable blade profile samples for subsequent aerodynamic optimization.

随着火箭发动机对高推重比要求的提高，提高涡轮泵内超声速涡轮的性能已成为一项关键的技术挑战。然而，目前还没有有效的方法来设计超声速静叶型。针对这一缺陷，本研究提出了一种基于特性法的超声速定子设计方法。该方法通过求解控制流方程并将其积分到参数化叶片型线中，生成膨胀轮廓。这使得能够高效和精确地生成满足马赫数规格和结构约束的叶片几何形状。在一个燃料涡轮泵的案例研究中，三维数值模拟表明，设计的超音速定子为转子进口提供了周向均匀的流动，从而使整个叶尖间隙范围内的效率提高了25%。设计点的流场分析表明，定子设计显著降低了出口激波损失，其中尾迹损失和端壁边界层摩擦损失占主导地位。此外，叶尖泄漏涡和转子上/下通道涡几乎占据了涡轮出口的整个流道，占涡轮总损失的76%。非设计流场分析表明，转速的增加提高了临界压比，而压比的降低放大了通道内的逆压梯度，显著扩大了分离区。所提出的参数化超声速定子设计方法能够开发出轻量化、高性能的涡轮泵涡轮，同时为后续的气动优化提供有价值的叶片型面样本。

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引用次数: 0

Mechanistic insights into rotational curvature correction for turbulence modeling in high angles of attack separated flows 大迎角分离流湍流模拟中旋转曲率修正的机理研究

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-17 DOI: 10.1016/j.ast.2026.111708

Ruijie Bai, Hanqi Song, Jinrong Zhang, Chao Yan

Accurately simulating rotational and curvature effects remains a central challenge in turbulence modeling. This study investigates the effect of rotational curvature correction on the SST-DDES method in high angles of attack separated flow over the NACA4412 airfoil and its underlying mechanism. We reveal a novel physical mechanism whereby the rotational and curvature correction suppresses vortex stretching-particularly in streamwise and spanwise directions-via the curvature-sensitivity function F_r1, leading to reduced enstrophy. Key consequences include decreased vorticity growth, lower turbulent kinetic energy, and inhibited dissipation. Consequently, non-physical dissipation in the vortex core is significantly reduced, yielding sharper vortical structures and more accurate unsteady flow evolution. The identified chain of mechanisms-suppressed stretching, reduced enstrophy, and rebalanced production/dissipation-provides profound insight into curvature-sensitive flows.

准确模拟旋转和曲率效应仍然是湍流建模的核心挑战。本文研究了旋转曲率修正对NACA4412翼型大迎角分离流SST-DDES方法的影响及其潜在机制。我们揭示了一种新的物理机制，即旋转和曲率修正通过曲率敏感函数Fr1抑制涡旋拉伸，特别是在流向和展向方向，导致熵减少。主要结果包括减少涡量增长，降低湍流动能和抑制耗散。因此，涡核的非物理耗散显著减少，产生更清晰的涡结构和更精确的非定常流场演化。确定的机制链——抑制拉伸、减少熵和重新平衡生产/耗散——为曲率敏感流动提供了深刻的见解。

引用次数: 0

Effects of stall pattern and intensity on the single-degree-of-freedom aeroelastic behavior of airfoils 失速模式和强度对翼型单自由度气动弹性性能的影响

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-16 DOI: 10.1016/j.ast.2026.111720

Xuanlei Yang , Yuzhe Xu , Chuanqiang Gao

At high angles of attack (AOAs), stall produces unsteady, nonlinear aerodynamic force. Such force can trigger stall flutter and large structural oscillations, endangering the performance and safety of structure. Although airfoils of different thickness exhibit distinct stall patterns and intensities depending on the angle of attack, their specific effects on stall flutter dynamics remain inadequately understood. This study investigates the aeroelastic response of a single-degree-of-freedom (SDOF) pitching oscillator for a leading-edge-stall thin airfoil (NACA0012) and a trailing-edge-stall thick airfoil (DU 91-W2-250) using two-dimensional CFD-CSD coupled simulations and spectral analysis. In this study, the AOAs are categorized into three distinct regimes: linear, light stall and deep stall, based on variations in airfoil aerodynamic characteristics, thereby representing different levels of stall intensity. The simulation results indicate that the thin, leading-edge-stall airfoil is prone to structural instability in the light-stall regime due to the emergence of a low-frequency flow mode. However, the thick, trailing-edge-stall airfoil is more likely to exhibit structural instability in the deep-stall regime. A concise criterion from a quasi-steady aerodynamic model,

\frac{d C_{m}}{d α} |_{α = α_{0}} < 0

, predicts instability regions well across the test cases, and remains effective even in the deep stall regime. The finding implies that time-averaged flow quantities remain a key factor controlling coupled-response stability in stall flutter.

在大迎角时，失速会产生非定常的非线性气动力。这种力会引起失速颤振和较大的结构振荡，危及结构的性能和安全。尽管不同厚度的翼型根据迎角表现出不同的失速模式和强度，但它们对失速颤振动力学的具体影响仍未充分了解。本研究利用二维CFD-CSD耦合模拟和频谱分析研究了单自由度俯仰振荡器对前缘失速薄翼型（NACA0012）和尾缘失速厚翼型（DU 91-W2-250）的气动弹性响应。在本研究中，aoa被分为三种不同的制度：线性，轻度失速和深度失速，基于翼型气动特性的变化，从而代表不同水平的失速强度。仿真结果表明，薄前缘失速翼型在轻失速状态下，由于低频流动模态的出现，容易出现结构失稳。然而，厚，后缘失速翼型更有可能在深失速状态下表现出结构不稳定。准稳态气动模型的简洁判据dCmdα|α=α0<；0可以很好地预测所有测试用例的不稳定区域，即使在深度失速状态下也仍然有效。这一发现表明，时间平均流量仍然是控制失速颤振耦合响应稳定性的关键因素。

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引用次数: 0

Physics-informed sparse reinforcement learning for hybrid VTOL UAV control: HILS verification and tethered hover benchmarking 混合垂直起降无人机控制的物理信息稀疏强化学习：HILS验证和系留悬停基准测试

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-16 DOI: 10.1016/j.ast.2026.111646

Mohammed Osman , Yuanqing Xia , Mohammed Mahdi , Tayyab Manzoor , Ghulam E. Mustafa Abro , Abdulrahman H. Bajodah

Hybrid Vertical Take-Off and Landing (VTOL) UAVs present significant challenges for control design, particularly due to nonlinear dynamics, actuator coupling, and complex hover-cruise transitions. Conventional controllers, such as PID and gain-scheduled MPC, often lack robustness to uncertainties, while recent reinforcement learning (RL) methods remain computationally demanding and offer limited interpretability, restricting their suitability for embedded platforms. To address these limitations, this paper introduces a physics-informed sparse RL framework that combines Sparse Identification of Nonlinear Dynamics (SINDy) with RL. Unlike black-box policies, the proposed approach constructs symbolic models of dynamics, reward, and policy, yielding interpretable controllers that are lightweight, data-efficient, and dynamically consistent. The framework is validated on a hybrid UAV with blended quadrotor-fixed-wing dynamics using high-fidelity simulations, hardware-in-the-loop testing, and tethered prototype bench experiments executed in real time on an NVIDIA Jetson platform (no free-flight experiments are reported in this work). Results demonstrate reliable trajectory tracking, robust mode transitions, and efficient real-time execution, confirming the potential of SINDy-RL as a scalable pathway for physics-aware autonomy in next-generation VTOL UAV systems.

混合垂直起降（VTOL）无人机对控制设计提出了重大挑战，特别是由于非线性动力学，执行器耦合和复杂的悬停巡航转换。传统的控制器，如PID和增益调度MPC，通常缺乏对不确定性的鲁棒性，而最近的强化学习（RL）方法仍然需要计算，并且提供有限的可解释性，限制了它们对嵌入式平台的适用性。为了解决这些限制，本文引入了一个物理信息稀疏RL框架，该框架将非线性动力学的稀疏识别（SINDy）与RL相结合。与黑盒策略不同，所提出的方法构建了动态、奖励和策略的符号模型，产生了轻量级、数据高效和动态一致的可解释控制器。该框架在具有混合四旋翼-固定翼动力学的混合无人机上进行了验证，使用高保真仿真、硬件在环测试和在NVIDIA Jetson平台上实时执行的系绳原型实验（本工作中没有报告自由飞行实验）。结果证明了可靠的轨迹跟踪、稳健的模式转换和高效的实时执行，证实了SINDy-RL作为下一代垂直起降无人机系统中物理感知自主的可扩展路径的潜力。

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引用次数: 0

Dynamic task allocation for multi-UAVs in disaster scenarios: A novel two-level optimization method with forecasting 灾害场景下多无人机动态任务分配：一种带预测的两级优化方法

IF 5.8 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2026-01-16 DOI: 10.1016/j.ast.2026.111711

Quancheng Pu, Lu Yang, Tieshan Li

In disaster relief operations, unmanned aerial vehicles (UAVs) play a critical role in tasks such as search and rescue, material delivery, and monitoring, significantly improving rescue efficiency. However, the large-scale, dynamic, and diverse nature of these tasks poses substantial challenges to task allocation, as traditional methods often suffer from limited accuracy and slow response times. This study proposes a novel two-level task allocation mechanism that integrates a three-dimensional self-organizing map (3D-SOM) for initial task clustering and an auction-based optimization algorithm for refined allocation. Additionally, this research introduces a radial basis function multi-kernel extreme learning machine (RBF-MKELM), which achieves high-precision prediction of supply and demand changes even with limited data. Experimental results demonstrate that the proposed method outperforms nine benchmark algorithms, achieving an average performance improvement of 34.5% in single-type task scenarios and 33.9% in multi-type task scenarios. Compared to five other time-series forecasting models, the RBF-MKELM model improves prediction accuracy by 48.6%, highlighting its robustness in data-scarce environments. Simulation validations confirm the framework’s effectiveness in dynamic task reallocation for large-scale disaster scenarios, providing a scalable and practical solution for UAV swarm operations.

在救灾行动中，无人机在搜救、物资输送、监控等任务中发挥了关键作用，显著提高了救援效率。然而，这些任务的大规模、动态性和多样性给任务分配带来了巨大的挑战，因为传统的方法往往存在准确性有限和响应时间慢的问题。本研究提出了一种新的两级任务分配机制，该机制集成了用于初始任务聚类的三维自组织映射（3D-SOM）和用于精细分配的基于拍卖的优化算法。此外，本研究还引入了径向基函数多核极限学习机（RBF-MKELM），在有限的数据条件下实现了对供需变化的高精度预测。实验结果表明，该方法优于9种基准算法，在单类任务场景下的平均性能提高34.5%，在多类任务场景下的平均性能提高33.9%。与其他5种时间序列预测模型相比，RBF-MKELM模型的预测精度提高了48.6%，突出了其在数据稀缺环境中的鲁棒性。仿真验证验证了该框架在大规模灾难场景下动态任务再分配中的有效性，为无人机群作战提供了可扩展的实用解决方案。

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引用次数: 0