To investigate the reaction evolution during the reactive Al-rich PTFE/Al jet formation process, a multi-cabin vented chamber energy harvesting system was employed to measure the overpressure characteristics of the reactive jet. Combined with numerical simulations, the spatio-temporal energy release behavior was revealed, and the timing sequence reaction mechanism was elucidated. On this basis, an evaluation method based on the multi-cabin vented chamber was proposed, enabling decoupled and quantitative characterization of the penetration–explosion energy release behavior of reactive jets. The results indicate that, when flowing to a certain extent, reactive jets possess the capacity for self-activation, thereby inducing an ignition reaction. Following a stage of reaction growth, it evolves into overall deflagration. The ignition expands axially from the slug toward the jet head and radially outward from the central axis. The combined effects of temperature rise and the localized enrichment of Al particles in the slug region are likely the key mechanisms triggering ignition. Evaluation calculation results indicate that the actual energy released by the reactive jet during the formation process accounts for about 47.3% of the theoretical value. Analysis suggests that during initial shorter-range flow distance (0∼9.2CD), energy release of the reactive jet is not obvious and the energy dissipation is negligible, whereas during longer-range flow distance (9.2CD∼12.5CD), significant ignition occurs, causing lateral jet divergence and resulting in significant reactive energy loss.

This paper prepared a novel as-cast W-Zr-Ti metallic ESM using high-frequency vacuum induction melting technique. The above ESM performs a typical elastic-brittle material feature and strain rate strengthening behavior. The specimens exhibit violent chemical reaction during the fracture process under the impact loading, and the size distribution of their residual debris follows Rosin-Rammler model. The dynamic fracture toughness is obtained by the fitting of debris length scale, approximately 1.87 MPa & sdot;m1/2. Microstructure observation on residual debris indicates that the failure process is determined by primary crack propagation under quasi-static compression, while it is affected by multiple cracks propagation in both particle and matrix in the case of dynamic impact. Impact test demonstrates that the novel energetic fragment performs brilliant penetration and combustion effect behind the front target, leading to the effective ignition of fuel tank. For the brittleness of as-cast W-Zr-Ti ESM, further study conducted bond-based peridynamic (BB-PD) C++ computational code to simulate its fracture behavior during penetration. The BB-PD method successfully captured the fracture process and debris cloud formation of the energetic fragment. This paper explores a novel as-cast metallic ESM, and provides an available numerical avenue to the simulation of brittle energetic fragment. (c) 2025 Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Thermal response analysis of multi-material energetic systems containing thin insulated layers or material interfaces usually requires interface-conformal meshes in conventional finite element methods. This dramatically increases modeling cost and often makes geometrically complex configurations impractical to simulate. In this paper, a non-conformal finite element framework is developed for transient thermal analysis of energetic structures with interfacial discontinuities. An independent computational code is implemented in Python language. The proposed approach enables accurate simulation of temperature gradient jumps (weak discontinuities) across material interfaces and temperature jumps (strong discontinuities) across insulated layers on a simple background mesh, eliminating the need for conformal mesh adjustment. A temperature-dependent heat source term governed by Arrhenius kinetics is incorporated to describe exothermic decomposition. The formulation is validated against a one-dimensional benchmark and then extended to two-dimensional Cartesian and axisymmetric problems. Representative simulations of a segmented bar, a shaped charge and an insulated charge demonstrate the applicability to practical energetic configurations. The method provides an efficient computational tool for thermal response analysis of complex energetic structures.

During flight, guided munitions operate in severe cross‑domain aerodynamic environments and are subjected to external disturbances, which induce strong nonlinearities and model uncertainties that significantly degrade the control performance and robustness of the autopilot. Focusing on the combined requirements of high dynamic responsiveness and strong disturbance rejection for the three‑loop overload autopilot of skid‑to‑turn (STT) guided munitions, this paper introduces fuzzy logic into the linear active disturbance rejection control (LADRC) framework, proposes a fuzzy‑compensated extended state observer (FC‑ESO), and develops a three‑loop FC‑LADRC overload autopilot structure. Based on the traditional linear extended state observer (LESO), a multi‑channel fuzzy compensation mechanism is incorporated to achieve dual regulation of “parameter adaptation + real‑time estimate correction,” thereby effectively enhancing the dynamic disturbance estimation accuracy and noise suppression capability of the observer under severe aerodynamic parameter perturbations and strong noise. Using Lyapunov stability theory, the input‑to‑state stability (ISS) of the FC‑ESO error system is analyzed, and sufficient conditions for boundedness are derived, providing theoretical support for the stable application of the fuzzy‑compensated ESO. Comparative simulations with conventional controllers are then conducted to quantitatively evaluate the proposed method in terms of control signal quality, dynamic response, disturbance attenuation, and full‑trajectory robustness. The results demonstrate that, under wide‑range aerodynamic parameter variations and significant external disturbances, the proposed controller outperforms the benchmark methods in tracking accuracy, response speed, and disturbance‑rejection robustness, thereby significantly enhancing the overall control performance of the three‑loop overload autopilot for STT-guided munitions.

A high-density tungsten-zirconium-titanium (W-Zr-Ti) reactive alloy was prepared by powder metallurgy. This alloy exhibits high density, high strength, and violent energy release characteristics, resulting in outstanding penetration and ignition abilities. Dynamic impact experiment demonstrated its strain rate hardening effect, and the energetic characteristics were investigated by digital image processing technique and thermal analysis experiment. The results show that W-Zr-Ti reactive alloy performs compressive strength of 2.25 GPa at 5784 s-1 strain rate, and its exothermic reaction occurs at about 961 K. Based on the explosion test and shock wave theory, thresholds of enhanced damage effect are less than 35.77 GPa and 5.18x104 kJ/m2 for shock pressure and energy, respectively. Furthermore, the transformation of fracture behavior and failure mechanism is revealed, which causes the increase in compressive strength and reaction intensity under dynamic loading.

Cerium-aluminum (CeAl) alloy is promising reactive structural materials (RSMs) with significant potential for liner applications. To investigate the thermochemical characteristics of CeAl alloy and the perforation behavior of its liner impacting steel targets, a CeAl alloy liner with 5 wt% Al content was fabricated, with a cerium (Ce) liner and a copper (Cu) liner used as control. The microstructure and elemental distribution of the CeAl alloy were analyzed using SEM, EDS, and XRD. The thermochemical reaction mechanism of the CeAl alloy was examined through TG-DSC. Penetration experiments were conducted to explore the combined effects of invasion and implosion of CeAl alloy liner against steel target. The results indicate that the addition of Al leads to the formation of Ce3Al intermetallic compounds in the alloy and reduces the apparent activation energy of the Ce-based alloy by around 53.17%, thereby facilitating energy release. The presence of 5 wt% Al increases the calorific value by approximately 24.5%, and this change allows the oxidation process to be divided into three distinct stages. Compared to an inert copper liner, the average penetration diameter of the CeAl5 reactive alloy liner increases by around 42.78%. Furthermore, when compared to the Ce liner, the penetration depth of the CeAl5 reactive alloy liner increases by approximately 82.64%.

Peridynamic method has performed brilliant application prospects in many fields, especially the crack propagation and thermal-mechanical coupling problems. In this paper, a thermal peridynamic (TPD) simulation with McGuire-Tarver reaction kinetics model in the heat source is conducted for revealing the thermal response of energetic materials. This model takes account of multi-steps chemical reaction during the heating process and is appropriate for the crack condition. Herein, cook-off test simulation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX)-based aluminized explosive is carried out. Simulation results exhibit satisfactory accuracy compared with the previous experiments. The influence of heating rates and explosive component ratios on thermal response are also employed. The results show that heating rate plays an important rule on ignition time and position. The additions of HMX and AP are likely to trigger more violent exothermic chemical reaction during the ignition process. Particularly, cook-off model of warhead with crack is built and calculated. The results indicate that crack may lead to thermal accumulation and reaction aggravation of the explosive.

Aiming at the feature that the transfer alignment of inertial navigation system moving base is a nonlinear system in practical engineering, this paper establishes an accurate nonlinear filtering model for the transfer alignment of moving base by adopting the second-order Markov process to represent the dynamic deflection deformation in the process of transfer alignment and by applying the nonlinear filtering method to the process of transfer alignment of inertial navigation system. Finally, through the simulation comparison with the Kalman filtering method, the results show that the nonlinear filtering algorithm has obvious advantages in the alignment accuracy in the transfer alignment process of the inertial navigation system.

Titanium hydride (TiH2), a promising high-energy additive, is doped into PTFE/Al to optimize the energy output structure of the reactive jet and strive for better aftereffect damage ability to the target. Six types of PTFE/Al/TiH2 reactive liners with different TiH2 content are prepared by the molding and sintering method. The energy release characteristics of PTFE/Al/TiH2 reactive jet are tested by the transient explosion energy test, and are characterized from pressure and temperature. The reaction delay time, pressure history, and temperature history of the energy release process are obtained, then the actual value of released energy and reaction efficiency of the reactive jet are calculated. The results show that the peak pressure and temperature of the PTFE/Al/TiH2 jet initially increase and then decrease with increasing TiH2 content. When the TiH2 content is 10%, the actual value of released energy and reaction efficiency increased by 24% and 6.4%, respectively, compared to the PTFE/Al jet. The reaction duration of the reactive material is significantly prolonged as the TiH2 content increased from 0% to 30%. Finally, combined with the energy release behaviors of PAT material and the dynamic deformation process of liner, the enhancement mechanism of TiH2 on energy release of the reactive jet is expounded.

A ternary system of PTFE/Al/Bi2O3 is constructed by incorporating PTFE-based reactive material and thermite for enhancing the energy release of the PTFE-based reactive material. The effects of Bi2O3 in the PTFE/Al/Bi2O3 on both mechanical properties and the energy release were investigated through various tests such as thermogravimetry-differential scanning calorimetry, adiabatic oxygen bomb test and split Hopkinson pressure bar test. The microstructure observed through scanning electron microscope and X-ray diffraction results are used to analyze the ignition and reaction mechanism of PTFE/Al/Bi2O3. The results indicate that the PTFE/Al/Bi2O3 are capable of triggering the exothermic reaction of molten PTFE/Bi2O3 and Al/Bi2O3 over the PTFE/Al reactive materials, thereby promoting reactions. The excessive aluminum in the ternary system is beneficial for increasing energy release. The ignition of shock-induced chemical reactions in PTFE/Al/Bi2O3 is closely related to the material fracture. The dominant mechanism for hot-spot generation under Split Hopkinson Pressure Bar test is the frictional temperature rise at the microcrack after failure.

Aiming at the problem of poor transfer alignment accuracy between missiles with a high length-to-diameter ratio as a carrier missile and the internally carried guided submunition, this study proposes a transfer alignment method based on the distributed inertial network of the guided submunition. Initially, considering the influence of the deflection deformation of the carrier missile body and the dynamic nonlinear deformation of the lever arm on the transfer alignment accuracy, the corresponding error model is established and compensated for the sub-inertial guide velocity to improve the accuracy of the observed quantities. Additionally, in response to the high failure rate of low-cost inertial guidance systems equipped with guided submunition, we used an inertial network data fusion architecture based on the isolation of device failure monitoring, which effectively isolates the faulty data through the fusion of inertial measurements at the sensor level and optimal fusion of filtering to further improve the reliability of transmission alignment. The effectiveness of the method proposed in this paper is verified through a large number of simulation experiments. Compared with the traditional transfer alignment method between a single master inertial guide and a sub inertial guide, the method in the paper has obvious improvement in the transfer alignment accuracy. In addition, this method is not affected by the failure of inertial devices in the distributed inertial network, and can continuously maintain a high transfer alignment accuracy. For this kind of missile-borne distributed inertial network with a sub-node sets layer, it is found after comparison that: the transmission alignment error is basically the same for different slave nodes in the same sub-node sets; between different sub-node sets, the closer to the master inertial guide the transmission alignment error is smaller. This study provides a new solution idea and certain reference value for solving the problem of poor transfer alignment accuracy between missiles with a high length-to-diameter ratio as a carrier missile and the internally carried guided submunition.

Abstract Impact experiment has been commonly used in deep space exploration and asteroid defence. In this paper, three types of rock fragmentation penetrators are employed, and the impact fragmentation process is simulated based on bond-based peridynamic (BB-PD) C++ computational code. The validity of computation is proved by the previous experimental and numerical research. Here, the influences of impact velocity and structure on the damaged mass of rock have been analyzed. The results show that the notched penetrator performs higher rock fragmentation efficiency. The structure of penetrator plays an important role on the damaged mass under the low impact velocity, and the penetrator mass becomes significant in the case of high impact velocity. Furthermore, the rock fragmentation mechanism has been revealed by analyzing the influenced regions and interaction effect. BB-PD simulation indicates the prospect of this notched penetrator for asteroid or planet rock fragmentation application.

为获得亚音速下不同弹体外形对机载布撒子弹药气动特性和初始外弹道性能的影响规律,采用FLUENT流体动力学计算软件对亚音速流中不同弹体外形的子弹药气动性能进行了仿真分析,建立了机载布撒子弹药的6自由度刚体外弹道分析模型,并基于龙格-库塔法求解其初始外弹道性能.研究结果表明:弹体外形影响下气体绕流表现出的层流/湍流行为是影响弹体所受气动力的重要因素.弹体头部突起对弹体气动特性影响不大;在0.72 Ma来流中,圆头弹型阻力系数和静力矩系数导数分别为0.349和0.86,相应为平头弹型的31.4％和46.7％;在总翼展面积相同时,增加尾翼数量会减小弹体所受气动升力,8片尾翼弹型的静力矩系数为6片尾翼弹形的58％;初始外弹道飞行时凹头弹型和6片尾翼弹型的攻角收敛更快,径向转动惯量增大时攻角收敛速率减慢.研究结果可为布撒武器子弹药的相关设计提供一定参考.

针对反跑道弹药战斗部对机场跑道内爆毁伤效应评估的需求,为系统开展机场跑道在装药内爆载荷作用下的毁伤效应研究与构建工程函数模型,在量纲分析的基础上开展不同装药质量、不同装药埋深下的机场跑道内爆毁伤实验和数值仿真,探究装药量和装药埋深对机场跑道毁伤形态以及毁伤场参数的影响规律.研究结果表明:装药量一定时,有效毁伤半径Red随装药埋深的增加呈先增大、后减小的趋势;装药埋深一定时,毁伤效应参量随装药量的增加而增大;装药量和装药埋深的最适匹配可达到理想的毁伤效果.基于实验与数值仿真研究获得的弹坑形态和裂纹特征与跑道内爆炸作用机理分析,提出将毁伤模式和毁伤场特征参量相结合的评估方法来有效表征多层混凝土介质内爆毁伤效应,采用敞坑、隆起和隐坑3种毁伤模式来描述跑道的破坏形态,采用特征参量弹坑半径Rc、有效毁伤半径Red、最大爆腔半径Ric,以及弹坑深度H定量描述跑道内爆毁伤场区域;结合大量仿真和实验数据拟合得到机场跑道内爆毁伤模式和毁伤场特征参量的工程化函数模型,可对机场跑道内爆毁伤效应进行快速预测.

为研究Al粒径对50％:50％质量比的富铝聚四氟乙烯基铝(PTFE/Al)活性材料在中高应变率下的冲击反应行为的影响,采用模压烧结成型法制备了50 nm、10μm、70μm、200μm 4种Al粒径的PTFE/Al活性材料试件.基于分离式霍普金森压杆(SHPB)实验,利用高速摄像机拍摄不同应变率加载下PTFE/Al活性材料的冲击反应过程,分析Al粒径对PTFE/Al活性材料的冲击反应特性影响.实验结果表明:随着Al粒径从50 nm增加到10μm,反应延迟时间增加可达40％,反应持续时间降低可达17％,同时PTFE/Al活性材料参与反应的量逐渐减少,反应激烈程度和能量释放不断降低,反应难以持续进行;当Al粒径增加到70μm时,难以在SHPB加载下发生反应;加载应变率对PTFE/Al活性材料的反应性能也有较大的影响,PTFE/Al活性材料的反应延迟时间随着加载应变率的提高而降低;加载应变率和Al粒径对PTFE/Al活性材料的冲击反应扩散、反应速率、反应程度均有较大影响,可通过调节Al粒径来调节其冲击反应性能.

In order to investigate the damage efficiency of smart micro torpedo armed with EFP warhead, and to reveal its penetration ability, experiment and simulation of EFP forming and penetrating underwater double-layer targets are carried on. In this paper, influence of the distance between EFP warhead and targets underwater is studied, which covers 0, 40, 120, 200, 280mm depth of water. In addition, a penetrator is exceeded by different kinds of buffer materials. The experiments show that, compared with EFP in the air, EFP formed by underwater weapon results in smaller holes on the double-layer target. With the increase of the depth of water, the projectile loses its mass and velocity and damage diameter of the target remains an approximate constant first and then decreases. Interestingly, the simulation demonstrates a unique damage mechanism different from that in the air, which affected by the penetrator and underwater shock wave

构建了中空型预控破片战斗部的破片初速分析模型，并利用有限元分析软件ANSYS/LS-DYNA,对中空型预控破片战斗部采用一端环形起爆和多点同时起爆时的预控破片成型过程进行了数值模拟。研究结果表明：采用一端环形起爆时，预控破片初速的理论计算结果与数值仿真结果吻合较好，最大偏差仅为3.54%;采用一端2点、3点、4点同时起爆时，周向方向上，分别距起爆点90°、60°和45°方位处的预控破片初速最高，且2点同时起爆时破片最大速度增益和平均速度增益均高于3点、4点同时起爆；此外，根据所研究的战斗部尺寸结构，当采用一端2点同时起爆，且起爆点设置距内壳体15 mm时，中空型预控破片战斗部能发挥更大的毁伤威力。研究结果可为相关战斗部的设计提供一定参考。

为研究药型罩球缺角对多功能战斗部威力性能的影响,基于有限元分析软件ANSYS/LS-DYNA对多功能战斗部作用过程进行数值模拟.研究结果表明:随着药型罩球缺角从120°增加到160°,聚能侵彻体尾部直径减小11.4％,长度增加37.8％,头部速度增加7.8％,尾部速度减小17％;针对混凝土/土壤靶板侵彻深度增加27％,开孔孔径随药型罩球缺角增加而减小;预制破片最高初速降低3.8％,破片飞散角减小了6.9％.