Aerospace Science and Technology最新文献_第2页

Trajectory tracking control of a morphing UAV using radial basis function artificial neural network based fast terminal sliding mode: Theory and experimental 使用基于径向基函数人工神经网络的快速终端滑动模式对变形无人机进行轨迹跟踪控制：理论与实验

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-08 DOI: 10.1016/j.ast.2024.109719

Saddam Hocine Derrouaoui , Yasser Bouzid , Aymen Doula , Mohamed Amine Boufroua , Amina Belmouhoub , Mohamed Guiatni , Aicha Hamissi

Lately, Morphing Aerial Systems (MASs) have seen a surge in demand due to their exceptional maneuverability, flexibility, and agility in navigating complex environments. Unlike conventional drones, MASs boast the ability to adapt and alter their morphology during flight. However, managing the control and stability of these innovative and unconventional vehicles poses a significant challenge, particularly during the aerial transformation phases. To solve this problem, this manuscript proposes a Radial Basis Function Artificial Neural Network-Based Fast Terminal Sliding Mode Control (RBFANN-FTSMC) method. This approach is designed to effectively manage morphology changes, ensure precise trajectory tracking, and mitigate the impact of external disturbances and parameter uncertainties. Accordingly, the RBFANN-FTSMC will be evaluated against Proportional Integral Derivative (PID), Sliding Mode (SM), and Fast Terminal Sliding Mode (FTSM) controllers through two flight simulation scenarios to validate its effectiveness. Additionally, the control parameters will be optimized using a recent metaheuristic algorithm known as the Whale Optimization Algorithm (WOA). A novel hardware control diagram is explained. Finally, the ability to alter morphologies and the results of experimental tests are discussed to highlight the performance and limitations of the mechanical structure and the implemented RBFANN-FTSMC.

近来，变形航空系统（MAS）因其卓越的机动性、灵活性和在复杂环境中的敏捷性而需求激增。与传统的无人机不同，MAS 能够在飞行过程中适应和改变其形态。然而，如何管理这些创新的非传统飞行器的控制和稳定性是一项重大挑战，尤其是在空中变换阶段。为解决这一问题，本手稿提出了一种基于径向基函数人工神经网络的快速终端滑模控制（RBFANN-FTSMC）方法。该方法旨在有效管理形态变化，确保精确的轨迹跟踪，并减轻外部干扰和参数不确定性的影响。因此，RBFANN-FTSMC 将通过两个飞行模拟场景，与比例积分微分（PID）、滑动模式（SM）和快速终端滑动模式（FTSM）控制器进行对比评估，以验证其有效性。此外，还将使用一种名为 "鲸鱼优化算法"（WOA）的最新元启发式算法对控制参数进行优化。此外，还解释了一种新颖的硬件控制图。最后，讨论了改变形态的能力和实验测试结果，以突出机械结构和实施的 RBFANN-FTSMC 的性能和局限性。

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引用次数: 0

Robust control of Chat-PM: A switched singular system with mode-dependent bounded nonlinearity Chat-PM 的鲁棒控制：具有模式相关有界非线性的开关奇异系统

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-07 DOI: 10.1016/j.ast.2024.109718

Chengzhe Han, Lixian Zhang, Yihang Ding, Yifei Dong, Yimin Zhu, Tong Wu, Jianan Yang

This paper is concerned with the robust control of the composite hybrid aerial-terrestrial precise manipulator (Chat-PM), a quadrotor-based robot with aerial/terrestrial movement and payload transportation capabilities. Given the distinct dynamics between aerial and terrestrial locomotion modes, Chat-PM is modeled as a type of switched singular system. A nonlinear term is contained in the system to model the coupling between translational and rotational movements of Chat-PM, which is proven to be norm-bounded and mode-dependent. Besides, the estimation error of the robotic arm's interaction force/torque is treated as the disturbance of the system. By means of the mixed

H_{2}

/

H_{\infty}

approach, numerically testable stability criteria are obtained, based on which the existence conditions for controllers with satisfactory transient and disturbance attenuation performance are provided. Compared to traditional studies assuming the nonlinearity term to be mode-independent, the conservatism in the controller design is reduced. Experimental results are provided to demonstrate the effectiveness of the proposed approach.

本文关注的是空中-地面精密混合机械手（Chat-PM）的鲁棒控制，这是一种基于四旋翼的机器人，具有空中/地面运动和有效载荷运输能力。鉴于空中和地面运动模式之间截然不同的动态特性，Chat-PM 被建模为一种开关奇异系统。系统中包含一个非线性项，用于模拟 Chat-PM 平移和旋转运动之间的耦合，该非线性项被证明是有规范约束且与模式相关的。此外，机械臂相互作用力/力矩的估计误差被视为系统的干扰。通过混合 H2/H∞ 方法，得到了可数值检验的稳定性准则，并在此基础上提供了具有令人满意的瞬态和扰动衰减性能的控制器的存在条件。与假定非线性项与模式无关的传统研究相比，减少了控制器设计中的保守性。实验结果证明了所提方法的有效性。

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引用次数: 0

Unsteady aerodynamic modeling and flight trajectory simulation of dual-spin projectile based on DNN and transfer-learning 基于 DNN 和迁移学习的双旋弹丸非稳态气动建模和飞行轨迹仿真

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-06 DOI: 10.1016/j.ast.2024.109711

Wen Ji , Chunlin Gong , Xuyi Jia , Chunna Li , Gang Wang

To evaluate flight performance and aerodynamic characteristics of a dual-spin projectile, the coupled computational fluid dynamics and rigid body dynamics (CFD/RBD) method is commonly used, which can simultaneously solve the flight mechanics and flow field. However, the efficiency is compromised by the large number of CFD calculations required. This paper develops an unsteady aerodynamic modeling method that combines deep neural networks and transfer learning, which can accurately predict unsteady aerodynamics of dual-spin projectiles under varying initial conditions. Considering the influence of flight state and aerodynamic data from short-term historical moments, we integrate them as input features of the aerodynamic model to reduce the impact of long-term historical data. To enhance the model generalization under varying initial conditions, we fine-tune the built aerodynamic model using small amounts of data under new conditions by transfer learning. The proposed method is validated through interpolated and extrapolated prediction cases, respectively. The results indicate that the proposed method can achieve better accuracy and generalizability than long short-term memory neural networks and autoregressive moving average method in unsteady aerodynamic modeling of the dual-spin projectile. By coupling the flight dynamics equations with the aerodynamic model in the time domain, the flight simulation only takes a few seconds, which can reduce computing time by three orders of magnitude compared to the coupled CFD/RBD method.

为评估双旋弹丸的飞行性能和气动特性，通常采用计算流体动力学和刚体动力学（CFD/RBD）耦合方法，该方法可同时求解飞行力学和流场。然而，由于需要进行大量的 CFD 计算，因此效率大打折扣。本文开发了一种结合深度神经网络和迁移学习的非稳态气动建模方法，可以准确预测不同初始条件下双旋翼弹丸的非稳态气动性能。考虑到短期历史时刻的飞行状态和气动数据的影响，我们将其整合为气动模型的输入特征，以减少长期历史数据的影响。为了提高模型在不同初始条件下的泛化能力，我们通过迁移学习，利用新条件下的少量数据对建立的空气动力学模型进行微调。分别通过内插和外推预测案例对所提出的方法进行了验证。结果表明，与长短期记忆神经网络和自回归移动平均法相比，所提出的方法在双旋翼弹丸的非稳态气动建模中可以获得更好的精度和泛化能力。通过在时域中耦合飞行动力学方程和气动模型，飞行模拟只需几秒钟，与耦合 CFD/RBD 方法相比，计算时间可减少三个数量级。

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引用次数: 0

Investigation of the aerodynamic performance of the dragonfly-inspired tandem wings considering the coupling between the stroke plane and phase difference 考虑冲程平面与相位差耦合的蜻蜓启发式串联翼气动性能研究

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-06 DOI: 10.1016/j.ast.2024.109717

Xiaojun Yang , Yang Luo , Xinyu Lang , Wei Wang

The dragonfly's tandem wings can make full use of the interference of various spatial vortices to obtain efficient flight capability. The complex coupling among multiple motion parameters will have an important influence on the interference between the forewing (FW) and hindwing (HW). In this paper, the aerodynamic performance of the dragonfly-inspired tandem wings is analyzed using the Computational Fluid Dynamics (CFD) method considering the coupling effect of the stroke plane and phase difference. The variation of the force coefficient, vortex structure and aerodynamic efficiency of the tandem wings in forward flight are analyzed, respectively. The results show that the stroke plane angle affects the distribution of the leading edge vortex (LEV) and trailing edge vortex (TEV), which primarily controls the trend of horizontal force variation. The phase difference of tandem wings will change the fluctuation of the horizontal force coefficient curve by affecting the meeting time of the forewing and hindwing. However, with the increase of stroke plane angle, the fluctuation of aerodynamic coefficient caused by phase difference will decrease. The propulsion efficiency(η) and power loading(PL) can be improved through increasing the stroke plane angle and selecting a reasonable phase difference. The conclusion can provide theoretical guidance for the design of the dragonfly-inspired tandem flapping wing aircraft (DTFWA) and the choice of motion parameters.

蜻蜓的双翼可以充分利用各种空间涡流的干扰来获得高效的飞行能力。多种运动参数之间的复杂耦合将对前翼（FW）和后翼（HW）之间的干涉产生重要影响。本文采用计算流体动力学（CFD）方法分析了蜻蜓启发式串联翼的气动性能，考虑了冲程平面和相位差的耦合效应。分别分析了前飞时串联翼的力系数、涡流结构和气动效率的变化。结果表明，冲程平面角度会影响前缘涡流（LEV）和后缘涡流（TEV）的分布，主要控制水平力的变化趋势。串联翼的相位差会影响前翼和后翼的交会时间，从而改变水平力系数曲线的波动。但是，随着冲程平面角的增大，相位差引起的气动系数波动会减小。通过增大冲程平面角和选择合理的相位差，可以提高推进效率（η）和功率负荷（PL）。该结论可为蜻蜓启发的串联拍翼飞行器（DTFWA）的设计和运动参数的选择提供理论指导。

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引用次数: 0

Effect of local concave non-axisymmetric endwall profiling on endwall secondary flows of a highly-loaded turbine cascade 局部凹面非轴对称端壁剖面对高负荷涡轮级联端壁二次流的影响

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-05 DOI: 10.1016/j.ast.2024.109716

Zhiyuan Cao, Xinyu Hao, Xi Gao, Wei Guo

Non-axisymmetric endwall profiling (NAEP) has been widely utilized in reducing secondary flow loss of turbines. However, most of NAEP are designed for the endwall of the entire blade passage, which presents challenges to the design of cooling structures of turbine endwall. This study aims to explore the local concave non-axisymmetric endwall profiling (LCNP) method with the same effect as whole passage NAEP, and reveal the influence mechanism of LCNP on endwall secondary flow structures of a highly-loaded turbine cascade. Under the condition that the maximum depth of LCNP is unchanged, the axial length effect and pitchwise location effect of LCNP are studied, the influence mechanism of LCNP on the secondary flow loss is analyzed, and the genetic algorithm is utilized to optimize LCNP at the optimal position. Results show that as the axial length of the LCNP increases and the pitchwise location gets closer to the suction surface, the intensity and range of the passage vortex are decreased, and the total pressure loss coefficient (loss coefficient) of the turbine cascade is decreased. When LCNP is 100% axial chord in length and at the position of 2/9 pitch, the loss coefficient is reduced by 5.49%. LCNP was optimized at the optimal position, and the optimal LCNP reduced the loss coefficient of the turbine cascade by 6.73%. After the local concave endwall profiling, the loading in the middle of the endwall of the turbine cascade is reduced, and the intensity of the passage vortex is effectively inhibited, which is the mechanism that the loss coefficient of the turbine cascade is reduced. However, after the local concave endwall profiling, the loading in the trailing of the endwall of the turbine cascade is increased, the transverse migration of the new boundary layer in the endwall is accelerated, and the loss coefficient of the near endwall is increased.

非轴对称端壁仿形（NAEP）已被广泛用于减少涡轮机的二次流损失。然而，大多数非轴对称端壁剖面都是针对整个叶片通道的端壁设计的，这给涡轮机端壁冷却结构的设计带来了挑战。本研究旨在探索具有与全叶片通道NAEP相同效果的局部凹面非轴对称端壁剖面（LCNP）方法，并揭示LCNP对高负荷水轮机级联端壁二次流结构的影响机理。在 LCNP 最大深度不变的条件下，研究了 LCNP 的轴向长度效应和螺距位置效应，分析了 LCNP 对二次流损失的影响机理，并利用遗传算法优化 LCNP 的最佳位置。结果表明，随着 LCNP 轴向长度的增加和桨距位置越来越靠近吸气面，通道涡流的强度和范围减小，涡轮级联的总压力损失系数（损失系数）减小。当 LCNP 轴向弦长为 100%，且位于 2/9 节距位置时，损耗系数降低了 5.49%。LCNP 在最佳位置进行了优化，最佳 LCNP 使涡轮级联的损耗系数降低了 6.73%。局部端壁凹面仿形后，水轮机级联端壁中部的载荷减小，通道涡流强度得到有效抑制，这是水轮机级联损耗系数降低的机理。然而，局部凹形端壁剖分后，水轮机级联端壁尾部的载荷增加，端壁新边界层的横向迁移加快，近端壁的损耗系数增大。

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引用次数: 0

Numerical research on flow field structure and droplets distribution of kerosene-fueled rotating detonation ramjet engine 煤油燃料旋转爆破冲压式喷气发动机流场结构和液滴分布的数值研究

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-05 DOI: 10.1016/j.ast.2024.109713

Zheng Yushan, Liu Yu, Wang Chao, Wang Yitian

In order to reveal the multiphase flow field structure and fuel droplets distribution under rotating detonation ramjet engine fueled by liquid kerosene, non-premixed simulations coupled with an Euler-Lagrangian approach is adopted. Supersonic air is used as oxidizer and the total pressure and total temperature at the entrance of isolation are set as 1.2 MPa and 1100 K, respectively, with a Mach number of 1.9. It is shown that a single-wave is formed and typical rotating detonation wave structures are established under two different orifice spacing conditions, namely 2 mm and 6mm. A "rich oil and poor oxygen band" is formed and attributed to the inconsistent supply of fuel and air after the passage of the detonation wave. When the orifices spacing is increased from 2 mm to 6 mm, both obvious strips after the detonation wave and “n-type” deflagration structures near the contact surface are observed. Besides, the detonation wave front becomes discontinuous, as well as from the deflagration heat release distribution. Despite of the effect of the circumferential propagation of detonation wave, kerosene droplets still propagate mainly along the downstream direction. However, Kerosene droplets distribution shows obvious difference along the detonation wave propagation direction.

为了揭示以液态煤油为燃料的旋转爆燃冲压式喷气发动机的多相流场结构和燃料液滴分布，采用了欧拉-拉格朗日非预混合模拟方法。使用超音速空气作为氧化剂，隔离区入口处的总压力和总温度分别设定为 1.2 MPa 和 1100 K，马赫数为 1.9。结果表明，在 2 毫米和 6 毫米两种不同的孔口间距条件下，形成了单波和典型的旋转爆轰波结构。形成 "富油贫氧带 "的原因是爆轰波通过后燃料和空气的供应不一致。当喷孔间距从 2 毫米增加到 6 毫米时，既能观察到明显的爆轰波后条带，又能在接触面附近观察到 "n 型 "爆燃结构。此外，爆轰波前沿变得不连续，从爆燃放热分布来看也是如此。尽管受到爆轰波周向传播的影响，煤油液滴仍主要沿下游方向传播。但煤油液滴的分布沿爆燃波传播方向有明显差异。

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引用次数: 0

Nonlinear vibration characteristics and damage detection method of blade with breathing fatigue crack 带呼吸疲劳裂纹叶片的非线性振动特性和损伤检测方法

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-04 DOI: 10.1016/j.ast.2024.109715

Yue Liu , Weifeng Long , Yugang Chen , Haifeng Hu

In aero-engine, blades operate under harsh conditions for extended periods, which makes them highly susceptible to fatigue cracks. The localized and nonlinear structural changes caused by blade crack lead to complex vibration characteristics that are not well understood, posing challenges to the identification of these cracks. This paper proposes an approach for identifying breathing fatigue crack in compressor blade, leveraging the nonlinear features induced by the cracks. Crucial sensitive characteristics are extracted and a crack indicator for accurate crack detection is defined. Initially addressing the typical morphology of fatigue breathing cracks, a dynamic model of blade with cracks is developed to analyze their impact on the natural frequencies. Nonlinear contact forces are introduced to characterize the "breathing" effect of the fatigue crack, allowing for the determination of the harmonic distribution patterns in the blade's vibration response under various excitation conditions. A finite element model is then established considering the crack morphology, by adopting the contact element. Based on that, the nonlinear response characteristics associated with the blade's primary, sub-harmonic, and super-harmonic resonances are explored. A crack-sensitive parameter is defined and extracted from the nonlinear responses, under different crack propagation stages. At last, effectiveness and reliability of the defined parameter for identifying cracks is validated through a vibration fatigue test.

在航空发动机中，叶片长期在恶劣条件下运行，极易出现疲劳裂纹。叶片裂纹引起的局部非线性结构变化导致了复杂的振动特性，而人们对这些特性的理解还不够深入，这给识别这些裂纹带来了挑战。本文提出了一种利用裂纹引起的非线性特征识别压缩机叶片呼吸疲劳裂纹的方法。本文提取了关键的敏感特征，并定义了用于准确检测裂纹的裂纹指标。首先针对疲劳呼吸裂纹的典型形态，开发了带有裂纹的叶片动态模型，以分析其对固有频率的影响。引入非线性接触力来描述疲劳裂纹的 "呼吸 "效应，从而确定各种激励条件下叶片振动响应的谐波分布模式。然后，通过采用接触元素，建立了一个考虑到裂纹形态的有限元模型。在此基础上，探讨了与叶片的主谐波、次谐波和超谐波共振相关的非线性响应特性。从不同裂纹扩展阶段的非线性响应中定义并提取了裂纹敏感参数。最后，通过振动疲劳试验验证了所定义参数在识别裂纹方面的有效性和可靠性。

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引用次数: 0

Effects of additional transmission chamber on flow dynamics of a pulsed jet in crossflow 附加传输室对横流脉冲射流流动动力学的影响

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-02 DOI: 10.1016/j.ast.2024.109712

Weimei Quan, Wenjing Sun, Jingzhou Zhang, Xiaoming Tan, Yuanhao Li

This study examines the effects of an additional transmission chamber on a pulsed jet in crossflow using experimental and Large-eddy simulation methods, with a focus on the structural and mixing characteristics of the flow. Three pulse frequencies are selected (f = 20 Hz, 50 Hz, and 100 Hz), and the results of the model with an additional transmission chamber are compared with the round pipe model. The results show that the additional transmission chamber enhances jet penetration, diffusion, and mixing uniformity, particularly at higher pulse frequencies. The additional transmission chamber also alters the exit velocity profile, increasing peak velocity and promoting greater deflection under crossflow. These findings highlight the potential of transmission chambers to optimize pulsed jet performance in applications requiring effective mixing and penetration.

本研究采用实验和大涡流模拟方法研究了附加传输室对横流中脉冲射流的影响，重点关注流动的结构和混合特性。选择了三种脉冲频率（f = 20 Hz、50 Hz 和 100 Hz），并将带有附加传输室的模型结果与圆管模型进行了比较。结果表明，附加传输室增强了射流的穿透、扩散和混合均匀性，尤其是在较高的脉冲频率下。额外的传输室还改变了出口速度曲线，增加了峰值速度，并促进了横流下更大的偏转。这些发现凸显了传输室在需要有效混合和穿透的应用中优化脉冲射流性能的潜力。

引用次数: 0

Multi-fidelity simulation of inlet mode transition with smooth thrust of turbine based combined cycle 多保真模拟涡轮机联合循环平滑推力的进气模式转换

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-11-01 DOI: 10.1016/j.ast.2024.109710

Jun Liu , Jinsheng Zhang , Zhengxu Hua , Keyu Zhou , Huacheng Yuan

A multi-fidelity simulation method of external and internal flow has been developed using commercial software to achieve a smooth thrust of the turbine-based combined-cycle (TBCC) propulsion system. This platform enables the investigation of the flow field and performance of the TBCC propulsion system at different mode transition schemes. The integrated multi-fidelity simulation includes the inlet, turbojet engine, ramjet engine, and nozzle, providing insights into the operation process of the TBCC propulsion system during the transition from turbojet mode to ramjet mode. Three mode transition schemes are proposed: critical mode transition, constant aerodynamic interface plane (AIP) Mach number mode transition, and linear mode transition. From the perspective of TBCC inlet, the performance of the critical mode transition exhibits the best performance among these mode transition schemes, while the linear mode transition performs the worst. However, from the viewpoint of the TBCC propulsion system and the hypersonic vehicle, the performance of constant AIP Mach number mode transition is the best. The non-dimensional thrust increases almost linear from 1.0 to 1.2, enabling hypersonic vehicle to accelerate steadily during the transition from turbojet mode to ramjet mode.

利用商业软件开发了一种外部和内部流动的多保真模拟方法，以实现基于涡轮机的联合循环（TBCC）推进系统的平稳推力。该平台可用于研究不同模式转换方案下 TBCC 推进系统的流场和性能。多保真度集成仿真包括进气口、涡轮喷气发动机、冲压喷气发动机和喷嘴，有助于深入了解 TBCC 推进系统从涡轮喷气模式过渡到冲压喷气模式的运行过程。提出了三种模式转换方案：临界模式转换、恒定气动界面平面（AIP）马赫数模式转换和线性模式转换。从 TBCC 入口的角度来看，临界模式转换的性能在这些模式转换方案中表现最好，而线性模式转换的性能最差。然而，从 TBCC 推进系统和高超音速飞行器的角度来看，恒定 AIP 马赫数模式转换的性能最好。非尺寸推力从 1.0 到 1.2 几乎呈线性增长，使高超音速飞行器在从涡轮喷气模式过渡到冲压喷气模式的过程中稳步加速。

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引用次数: 0

Study on concentration distribution and detonation characteristics of typical multiphase fuel in orthogonal flow field 正交流场中典型多相燃料的浓度分布和爆炸特性研究

IF 5 1区工程技术 Q1 ENGINEERING, AEROSPACE

Aerospace Science and Technology

Pub Date : 2024-10-31 DOI: 10.1016/j.ast.2024.109704

Linghui Zeng , Zhongqi Wang , Jianping Li , Xing Chen

The fuel concentration distribution and detonation characteristics are important for performance evaluation. In order to meet the needs of airdrop, launcher and missile, the transient flow and detonation process of multiphase fuel in orthogonal flow field are analyzed by experiments and numerical simulations. The dynamic detonation model of ethyl ether (EE), propylene oxide (PO) and tetrahydro dicyclopentadiene (JP-10) is built. The flow process, concentration distribution, overpressure, temperature and detonation wave structure of the three fuels are obtained. The results show that the falling velocity has obvious influence on the detonation process of fuel droplets. The falling velocity of 0.5 Ma makes the fuel concentration distribution more uniform and the energy output is better. The peak overpressure of EE, PO and JP-10 is 2.88 MPa, 3.21 MPa and 2.96 MPa respectively. The peak temperature is 2885 K, 3230 K and 2955 K respectively. The burn out rate increases by 8.5%, 8.1% and 13.7% respectively. JP-10 has higher sensitivity to falling velocity, and there are obvious secondary peaks of overpressure in low-speed state. PO has higher stability for falling velocity, and the scaled length of high temperature/pressure after detonation wave is 0.145 m·kg^-1/3.

燃料浓度分布和爆炸特性对性能评估非常重要。为了满足空投、发射和导弹的需要，通过实验和数值模拟分析了多相燃料在正交流场中的瞬态流动和起爆过程。建立了乙醚（EE）、环氧丙烷（PO）和四氢双环戊二烯（JP-10）的动态引爆模型。得到了三种燃料的流动过程、浓度分布、过压、温度和爆轰波结构。结果表明，下落速度对燃料液滴的起爆过程有明显影响。0.5 Ma 的下降速度使燃料浓度分布更均匀，能量输出更好。EE、PO 和 JP-10 的峰值超压分别为 2.88 MPa、3.21 MPa 和 2.96 MPa。峰值温度分别为 2885 K、3230 K 和 2955 K。烧损率分别增加了 8.5%、8.1% 和 13.7%。JP-10 对下降速度的敏感性较高，在低速状态下有明显的次生超压峰。PO 对下降速度的稳定性较高，爆炸后高温/高压波的比例长度为 0.145 m-kg-1/3。

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引用次数: 0