In order to improve the damping performances of suspension systems for tank and armored vehicle, a basic structure with"inerter-spring” quasi-zero stiffness is proposed. Dynamic simulation and parameter optimization of inerter continuous control and inerter on-off control are carried out with the parallel structure of inerter, spring and damper as suspension system. The results show that the vibration acceleration of vechile body is greatly reduced and the ride comfort is obviously improved with the quasi-zero stiffness control strategy. At the same time, the damping coefficient is reduced and the damping efficiency is improved. By analyzing the instantaneous power of each component in the process of suspension damping, it is found that the controllable inerter plays an role in energy compensation so that a part of the vibration energy can be transferred and converted dynamically and repeatedly between the spring and inerter, breaking through the traditional damping mechanism of spring buffer energy storage and damping heat generation energy consumption, and achieving better damping efficiency.

To enhance the combustion efficiency of boron, n-B/n-Ti/NC ternary spherical agglomerated particles were prepared by using swelling, adsorption, dissolution agglomeration, and prilling method.SEM and DSC were used to analyze the microscopic structural properties and thermal stability of the particles, and a laser ignition system was used to investigate their combustion characteristics.The results show that n-B and n-Ti can be adsorbed into the swelling NC capillary tubes, resulting in the formation of ternary spherical agglomerate particles with uniform distribution of elements, high density and high sphericity with n-Ti as a combustion improver and n-B as high-energy combustor.At the mass ratio of NC 17%, n-Ti 8% and n-B 75%, the agglomerated particle exhibits the shortest ignition delay time(3.42ms)and combustion time(8ms).The compatibility of n-B, n-Ti and NC is very good, and the agglomerated particles have excellent thermal stability.

Aiming at the mechanism, regularity characterization, influence factors and inhibition of ingredient migration in propellants, gun propellants and explosives, the ingredient migration theories which are mainly driven by concentration gradient and polarity action were introduced. The characterization methods of migration ingredients amount and migration ability based on advanced analytical techniques and migration kinetics were summarized. The effects of temperature, intermolecular interactions, crosslinking density, steric hindrance, structure, and other factors on ingredient migration were elaborated. The migration inhibition methods including chemical synthesis, material modification, and additive methods were discussed. The development directions of establishing rapid and non-destructive characterization methods of ingredient migration, improving migration models and synthesizing new ingredients with high anti-migration performance were proposed.Attached with 79 references.

The near-field blast wave characteristics(0.06m/kg^1/3<Z<1m/kg^1/3)of typical charge structures(sphere and cylinder)are investigated for supporting the protection of sympathetic detonation through near-field explosion experiment and numerical simulation.The load of near-field blast wave of cylindrical charge is experimentaly investigated,and a numerical caculation model of near-field explosion is established,The near-field blast wave structures and spatial distributions for peak parameters of spherical and cylindrical charges are analyzed.The results show that the near-field explosion loads are affected by the detonation products,and the reflected overpressure histories exhibit multi-peak and jagged form,which are due to the effects of multiple reflection waves and the complex flow of detonation products after the Mach region.The inverse of pressure and density gradient between detonation products and shock wave interface leads to the Rayleigh-Taylor instability effect.The generated interfacial microjets of detonation products promote the complexity of multiple reflection wave structure,resulting in large uncertainty of measured results of near-field reflected loads.The near-field incident overpressure curve shows a typical double-peak structure,which comes from the air shock wave and detonation products.Due to the structural effects of charge,the incident wave loads of cylindrical charge distribute non-uniformly along the axial and radial directions.The spatial distribution of incident parameters drastically varies when the azimuth angle is between 30°-60° because of the bridging wave effects.The modified predictive model can capture the incident peak overpressure and impulse in the range of 0.06m/kg^1/3<Z<1m/kg^1/3 for cylindrical charge(L/D=0.8)with center initiation under arbitrary azimuth angle,and the relative deviations among predicted results and numerical results of incident peak overpressure and impulse are less than 20%.

For solving the problems of nitrogen escape and splash in the droplet transfer process of high-nitrogen steel additive manufacturing, the experiment of droplet transfer in an ultrasonic frequency pulsed gas metal arc (UFP-GMA) additive manufacturing is carried out, and the influences of different ultrasonic frequency pulsed current superposition modes and pulse current frequencies on the stability of high-nitrogen steel droplet transfer are studied, The process parameters that can realize the stable droplet transfer of high-nitrogen steel additives were obtained. The experimental results show that the of one-pulse-one-droplet transfer can be realized under the pulsed gas metal arc (P-GMA) process conditions, but the transition stability is poor and the splash is obvious. Superimposing the ultrasonic frequency pulse current at the base current stage of P-GMA or both at the base and peak current stages is not conducive to the droplet transfer, and the problems such as short circuit and droplet explosion are prone to occur. When the low-frequency (20 kHz) pulse current is applied during the peak stage, its effect on droplet transfer is minimal. However, the medium-frequency (40-60 kHz) pulse currents can be superimposed to inhibit the generation of large particle splash, leading to improved stability in droplet transfer, but many small splashes will be formed during the transition when the frequency exceeds 60 kHz.

Thermobaric explosive is an fuel-rich explosive that can inflict severe damage to facilities and personnel in confined spaces due to the long-term pressure generated by explosion and combustion, as well as high-temperature fireballs. Thermobaric explosive involves the propagation of detonation waves in the charge, the scattering of fuel particles in space, and the subsequent combustion process of fuel particles. The coupling process of multi-scale, multi-material, multi-factor and multi-physical field causes the thermostatic damages, which is a significant area of damage research. This paper primarily discusses the research advances in the theoretical underpinnings of formulation design, the impact of formulation's primary components on thermobaric explosive performance and the performance evaluation of thermobaric explosive. It highlights that the future developments in thermobaric explosives will focus on the high chemical potential metal fuels and energy release techniques.Models for simulating the performance of thermobaric explosives should also be highly regarded. In conclusion, the formulation design based on large-scale data from simulations and tests will be a mainstay for driving the development of thermobaric explosives.

From the perspectives of reducing the influence of external stimuli and optimizing the structural design of energetic materials, the desensitization mechanisms of single compound energetic materials under different desensitization strategies are reviewed, including buffering, lubrication, conduction, heat absorption and insulation, improving the quality of energetic crystals and enhancing the stability of energetic molecules. The comprehensive desensitization mechanisms of multi-dimensional desensitization strategies such as using multifunctional desensitization materials and coupling various desensitization means are analyzed. The development directions of desensitization of energetic materials in the future are put forward: to develop energetic materials with both high-energy and insensitive characteristics, to research the relationship between desensitization mechanism of energetic materials and operational environment, and to build up universal quantitative description models of sensitivity from the molecular scale, providing theoretical guidance and technical support for designing new high-energy insensitive energetic materials. 93 References were attached.

In order to enhance the maximum dispersal speed of fuel during the explosion of fuel-air explosive (FAE) devices and achieve a more uniform speed distribution, the paper investigates the influences of detonation methods on the radial maximum speed of fuel dispersal in FAE device. Numerical simulation techniques are employed to analyze the influences above while maintaining the overall structure of the existing device. Specifically, the ALE algorithm implemented in LS-DYNA software is utilized to numerically simulate the fuel dispersal in a frustum-shaped FAE device. The changes in radial dispersal speeds of nodes located at identical positions under the conditions of single point initiation, multi-point initiation and approximate line initiation, are compared. The results demonstrate that positioning the initiation point closer to the unit exerts a restraining effect on the dispersal motion of the fuel within that specific element. Additionally, for a certain point on the fuel, the adoption of the approximate line initiation method proves effective in achieving a more uniform dispersal of fuel cloud and mist. This finding serves as a foundational step towards the further refinement of numerical simulations concerning FAE explosive fuel dispersal.

With the development of weapons and equipment towards diversification, versatility and systemization, modern warfare requires the increasingly high levels of command and decision-making in terms of overall planning, timeliness, and scientificity. The construction of task planning systems for major military powers is urgently needed and developed rapidly. In order to better promote the research of task planning systems, a comprehensive review is conducted on the tactical-level task planning methods. This paper reviews the development history of task planning systems and the methodological framework of tactical-level task planning, with a focus on summarizing the main implementation methods and future development directions of tactical-level task planning. In terms of the main implementation methods, the main methods involved in various aspects such as task description, task decomposition, task allocation and scheme evaluation are overviewed and analyzed. In terms of future development direction, the suggestions on standardization, universality, credibility, and other aspects are put forward.

When using infrared imaging to detect the scenes of flames generated by high-temperature combustion of objects and high-temperature fragments generated by object explosions,the rapid increase in scene temperature within the infrared imaging field of view leads to an increase in the dynamic range of infrared imaging,the image saturation,the loss of detail information,and the submergence of weak targets by high-temperature backgrounds.Therefore,it is urgent to develop an anti-fire interference high dynamic infrared imaging detection technology.This article briefly introduces the current development status of high dynamic infrared imaging technology with anti-fire interference capability.On this basis,the development trend of high dynamic infrared imaging detection technology with anti-fire interference capability is analyzed.

The magnetic gradient tensor system (MGTS) is the application basis for detecting the full tensor gradient field of magnetic target. Regional magnetic anomalies leads to a magnetic gradient tensor field, which MGTS uses as an information source to achieve the magnetic gradient tensor measurement through the differential calculation between vector magnetic sensors. Compared to the magnetic total field and vector field detection equipment, MGTS has high resolution, large information content, and strong anti-interference ability, which can obtain more potential physical property information of targets. The progress of target detection technology based on MGTSs worldwide is studied to provide theoretical reference and technical support for the modernization and informatization construction of magnetic detection equipment in China. The development process and stages of modern magnetic detection technology are elaborated, and then the two types of MGTSs based on superconducting technology and flux gate method, as well as their applications areintroduced and summarized. The calibration, compensation, noise reduction, magnetic target positioning and recognition technologies of MGTSs are reviewed. Finally, the design ideas for future high-precision magnetic gradient tensor detection instruments are prospected, and the current problems and development trends of various key technologies for magnetic gradient tensor detection are summarized.

Aiming at the pyrolysis and combustion process of the near burning surface of the pasty propellant, the laser ignition combustion experiment of the pasty propellant were carried out. At the same time, the pyrolysis and combustion characteristics of the near burning surface region of the pasty propellant were studied based on the multiphase chemical reaction numerical solver developed by the research group and the 14-component and 14-primitive chemical reaction equation. The macroscopic structure of propellant combustion flame was obtained through experiments and the burning rate of the pasty propellant was measured under constant pressure conditions. The combustion flame structure and chemical reaction sequence of the pasty propellant under constant pressure conditions were analyzed by numerical calculations. The effects of different ambient pressure on the combustion process of the pasty propellant were calculated. The results show that the fitted burning rate curve was in good agreement with the experimental results. In the range of experimental pressure, the burning rate of propellant in the combustion chamber of pasty rocket engine could be predicted well. The decomposition of AP is the first reaction in the combustion of pasty propellant, and the higher ambient pressure limited the diffusion of primary combustion gases, but enhanced the thermal feedback effect on the pasty domain, which increased the burning rate of the pasty propellant.

The overload signal of penetrating projectile is of vital importance to reflect the physical process of penetration, which further helps to reveal the mechanism of penetration resistance and the structural response of projectile. It is also an important basis for designing the projectile-fuze system and achieving the precise target strikes.The overload signal is divided into four components: rigid body deceleration, structural response of projectile, response of connection structure and interference signals of sensors. The sources and characteristics of the four components are introduced, and the modeling and evaluation methods for the vibration and sensor-related signals of projectile-fuze system are discussed. For analyzing the components of overload signals, the low pass filtering, mechanical filtering, modal decomposition, wavelet transform, and blind source separation methods are discussed respectively. The accuracies, adaptabilities, real-time performances, and applicabilities of the methods above are also compared. The real-time requirements for overload signal processing, the signal reconstruction methods, the form of rigid body deceleration in complex penetration environments and the challenges brought by high-speed penetration scenario are discussed. Based on the current research status of overload signals processing of penetrating projectiles, the existing problems and possible future research directions are summarized.

To support the theoretical design of the hypersonic missile's terminal effect and meet the development demand of penetration mechanics theory of non-circular projectiles, the penetration mechanism of non-circular projectilesis a key scientific problem required to be solved. A comprehensive review is conducted on the penetration behavior, penetration mechanism, ballistic stability, and structural response of non-circular projectiles.It is a review and summary of the existing research work, aiming to establish a basic framework for researching the penetration problem of non-circular projectiles.Moreover, the new phenomena and mechanisms introduced by the structural changes of non-circular projectiles are highlighted. Three suggestions for the future research of the non-circular projectiles are put forward for the reference of relevant researchers.

点火过程是内弹道的初始阶段,但由于点火过程的复杂性以及点火机理仍然不完善,点火过程始终不能与内弹道有机结合,使得目前工程上的内弹道计算只能忽略点火过程而直接选择点火压强作为计算初始点。以零维内弹道理论为基础,建立了点火过程3个阶段,即点火诱导期、火焰传播期和充气期的简化理论模型,可以与零维内弹道有机结合,从而完成了内弹道从环境压强(而不是点火压强)开始计算的完整过程。通过实例计算与验证,该模型能够很好展示在点火阶段燃烧室压强的建立过程,并可以计算得到点火延迟时间、火焰传播时间、点火药流量等点火参数,具有较高的预示精度,满足工程计算要求。研究表明,建立的点火过程理论模型与传统零维内弹道一样计算简便快捷,并具有较好精度的工程应用化特点。研究结果对于完善固体火箭发动机内弹道理论、提高固体火箭发动机内弹道预示精度,均具有重要的实际应用意义。由于采用了简化的点火过程理论模型,该结果不能直接用于点火性能的研究,只能用于零维内弹道性能的预估与计算。

Personnel are a critical factor in warfare.The damage effects of three types of damage elements,namely,shock wave,thermal effect and fragments,against personnel,are assessed based on the anti-personnel criterion through numerical simulation,experiment and theoretical computation tools.A damage zone of shockwave overpressure against personnel is delineated,and the relationship between scaled blast distance and personnel damage level is established,resulting in the minimum scaled blast distance of damage to personnel being 8.155m/kg^1/3.The spatial distribution of explosion thermal effect is calculated,and the free-field non-fuel air explosive or thermobaric bombs are not suitable for separate assessment of thermal effect on the personnel killing effect is put forward.The generation process of fragments is numerically simulated to obtain the quality,quantity and velocity of fragments.The simulated results are compared with the theoretically calculated results to assess the damage effect of the specific kinetic energy of fragments to personnel.The conclusions can provide reference for the design of warhead and the protection of battlefield personnel.

Explosive smoke bombs are of great significance in countering the infrared-guided weapons and protecting the high-value military targets. At present, most of the smoke simulation models do not take into account the vector information of explosion and the near-ground particle diffusion effect, and the authenticity of the explosion smoke simulation is low in the near-ground scene where the wall effect and the air turbulence phenomenon are significant. For the poor simulation accuracy of explosive smoke bomb in near-earth scene, a simulation method of explosive smoke bomb structure model in near-ground scene is proposed. This method uses the particle position information to replace the life cycle of the particle model. Based on the Gaussian puff model, a near-ground smoke explosion model considering the explosion flying direction of bomb and the wall effect is constructed to improve the simulation accuracy of near-ground smoke bomb explosion scene. The structural similarity (SSIM) analysis is used on the simulated image. After the best parameter selection experiment, the SSIM value reaches 0.944 3 and the standard deviation is ±0.000 5. The SSIM value of the proposed model is 0.011 2, 0.132 9 and 0.006 3higher than those of the particle system-Gaussian smoke model, ellipsoid explosion model and explosive smoke bomb model，respectively.The experimental results shows that the proposed model has clear direction information in smoke simulation, stronger ability to express the details of smoke turbulence and wall effect, and higher accuracy in the simulation of near-ground smoke bomb explosion scene.

During the electromagnetic launching process,the high speed sliding electrical contact about armature-rail is closely related to the accuracy of the rail spacing. Accurate measurement about the rail spacing can effectively guide the design of armature and researching for the matching about armature-rail. According to the cross-sectional,irregularly shaped characteristics,and the changing shape of the railgun. An high-precision measurement method for spacing size was proposed based on the angular bisector characteristic. In this method,the spatial position of two rails was divided into two segments that interest at a certain degree. The angular bisector was adopted as the measurement reference,and a measurement points were taken. The perpendicular lines of the two rails were drawn through the measurement point. The line connecting the two perpendicular feet was defined as the orbital spacing value. Through prototype design,comprehensive system error analysis,and comparative verification,a certain caliber railgun spacing engineering measurement was carried out. The results show that the measurement error is ≤0.05 mm,which satisfies the accuracy requirements. By obtaining accurate data of the rail spacing,an indispensable measurement method can be provided for numerical modeling,assembly process,and performance testing about electromagnetic launch devices.Thereby promoting the engineering application of railgun weapons.

In order to obtain the optimal casting process parameters of HTPB composite solid propellant, the constitutive model for the flow process of propellant slurry was established based on the rheological properties of HTPB propellant slurry adopting a combination of experimental and theoretical simulation methods. The casting process of HTPB composite propellant slurry was simulated by using the finite element software, and the reliability of the simulation results was verified through experiments. Moreover, the casting process of the propellant slurry was optimized and the optimal casting process parameters were obtained. The results show that HTPB propellant is a typical pseudoplastic fluid, and its viscosity decreases with increasing shear rate. The porosity and the casting time are 12.5% and 11.25%, respectively after comparison of experiment and simulation. Among them, temperature has the most significant impact on casting time, and vacuum degree has the most significant impact on porosity.

Time series matching technology is widely used in vehicle handling consistency evaluation.An evaluation method of vehicle throttle control action consistency based on segmented dynamic time warping (DTW) is proposed for the motion consistency evaluation of a coach vehicle in the process of cooperative driving.On the basis of the inconsistent number of sample data points in the cooperative control test of coach vehicle and the slope constraint of dynamic bending path, the traditional DTW rectangular search area is transformed into a parallelogram search area to reduce the area of the search area by changing the slope of search path, thus greatly reduce the calculation amount.Four groups of typical throttle action curves are selected to carry out 50 rounds of iterative experiments for verification, and the DTW distance matrix between the action curves of real vehicles A and B is calculated by segmented DTW method.A minimum deviation leveling method is used to combine the cluster objects for the actions of vehicles A and B, so as to complete the consistency evaluation of throttle action data.The experimental results show that the average matching accuracy of the improved DTW algorithm in each throttle action can reach 89.2%, which is about 3.2% higher than that of the single DTW algorithm, and the average matching time is about 92.45s, which is about 12.6% lower, thus verifying the feasibility and superiority of the segmented DTW algorithm in the consistency evaluation of throttle action.

The working principles and recent technological advancements of high-speed photography, spectroscopic testing, laser interferometry, and terahertz Doppler wave measurement techniques were introduced. Also, the application of these techniques in the field of explosive detonation testing was discussed. Among them, high-speed photography and laser interferometry are widely used in the measurement of detonation velocity, pressure, and shock initiation. Spectroscopic testing is mainly applied to detonation temperature measurement and detonation product composition analysis, while terahertz Doppler wave measurement is employed for explosive detonation wave measurement. The advantages and disadvantages of optical-electronic testing techniques in detonation performance research and provided an outlook on the future development of detonation performance testing technologies were analyzed. It is concluded that strengthening the study of micro-scale testing technologies for explosives, expanding the application of current optical-electronic testing techniques, and integrating data processing with big data technologies are key areas for future research in explosive detonation performance. 128 References were attached.

Three-dimensional woven preform (3DWP), because of its better formability and significant interlaminar bearing capacity, is expected to achieve the integrated molding of helmet curved surfaced, and reduce the waste of cut and raw materials. Because of the structure characteristics of ballistic helmet with multiple curved surfaces and high curvature, it is important to study the deformation mechanism of 3DWP during curved surface forming for the integrated forming of helmet. The curved surface formability of a layer-to-layer interlock 3DWP with stuffer yarns under high curvature and large deformation is studied systematically. The deformation mechanism and wrinkle defects formation mechanism of 3DWP are described comprehensively from in-plane/inter-layer dimensions and macro/mesoscale. The results indicate that significant in-plane shear deformation of 3DWP can be observed along the 45°direction at the same latitude. The maximum in-plane shear angle of the concave surface is 38°, which is greater than that of the convex surface. The maximum inter-layer shear angles of 3DWP warp and weft rows are 34.83°and 27.76°, respectively. After forming, 3DWP has reached 62° intra-ply shear locking angle, which induces the buckling of yarns microscopically and forms the ridged wrinkles macroscopically. In the wrinkle area, the maximum in-plane shear angle is only 4.8°, and the maximum inter-layer shear angle is 18°. This conclusion has guiding significance for structure selection and forming process of reinforced fabric for ballistic helmet in practical application.

Maritime manned/unmanned collaborative systems play a crucial role in enhancing naval operational effectiveness and represent a significant direction in the development of modern naval equipment. This paper focuses on the development of maritime manned/unmanned collaborative systems, reviews the current developing status and relevant foreign projects, clarifies the main characteristics of the systems, condenses and analyzes the scientific issues and key technologies involved, and ultimately provides a comprehensive survey on the development of maritime manned/unmanned collaborative systems. In the future, intelligence, modularity and sparsity will become the important directions for the development of maritime manned/unmanned collaborative systems. However, due to the contradictions between system autonomy and controllability, the development of intelligence and maritime constraints, and the features of manned/unmanned collaboration and existing collaborative frameworks, the system will also face challenges in scale, diversity, security, and intelligence-related aspects.

Unexploded ordnance refers to ammunition that has been disarmed, detonated, ignited or otherwise prepared for use or has been used, and has not exploded due to fuze failure, functional failure, design defects or other reasons after igniting, throwing, launching or burying for various reasons. The research status of safety disposal technology of unexploded ordnance at home and abroad is described,the unexploded ordnance detection technologies, such as magnetic detection, sound-magnetic compound detection and optical detection, and the non-contact disposal and destruction technology principles, such as burning treatment, blasting destruction, cutting treatment, are analyzed, and the advantages and disadvantages of different detection and disposal technologies and their application scenarios are summarized. At last, it is pointed out that the detection and disposal technologies of underwater unexploded ordnance are the focus of the current national defense field, and also the research hotspot. The research on key technologies of safe disposal of unexploded ordnance can provide theoretical basis for unmanned, safe and environmentally friendly detection and disposal of unexploded ordnance in the future.

With the wide application of intelligent collaborative algorithm and autonomous technology in the field of air,space and sea equipment,the multi-domain cluster distributed collaborative autonomous control technology has also been deeply studied,and significantly improved the degree of intelligent autonomy of unmanned equipment.Based on the development needs of distributed intelligent autonomous control technology of multi-domain cluster,this paper reviews the relevant references related to multi-domain cluster distributed intelligent autonomous control technology and the research status at home and abroad.The relevant strategies,key research directions and advanced methods of multi-domain cluster collaborative autonomous control technology are deeply analyzed.The relevant key technologies and methods are summarized,and the future development trend is discussed.This paper provides a reference for improving the collaborative autonomous control ability of unmanned cluster system.

Powdered fuel has broad application prospect prospects as fuels or additives in detonation propulsion systems due to their high energy density and excellent stability. Based on the classification of fuel types for gas-solid two-phase detonation and the application of powder detonation propulsion technology, the theoretical research progress on the detonation initiation and propagation characteristics of powdered fuel in oxidizer gas and gas fuel/oxidizer gas at domentically and internationally is reviewed. The theoretical and engineering aspects of heterogeneous detonation and hybrid detonation are summarized, highlighting the key factors affecting the initiation and propagation characteristics of gas-solid two-phase detonations, as well as important conclusions. Furthermore, the two-phase detonation engines are reviewed from the perspectives of application prospects, propulsion performance, difficulties and challenges, etc. Based on the summary of the numerical and experimental research status of powder detonation engines, the future research work that needs to be carried out is prospected.

In order to improve the safety performance of HMX, HMX/FOX-7 nano-cocrystals with different molar ratios were prepared by the ultra-low-temperature-assisted recrystallization method, where FOX-7 with low sensitivity was used as another component of the binary cocrystal. The morphology, structure, and thermal properties of the prepared HMX/FOX-7 cocrystals were characterized by SEM, XRD, FT-IR and DSC-TG, and their mechanical sensitivities were analyzed. The results show that the prepared HMX/FOX-7 crystals are mainly porous structure stacked with spherical particles, and their particle sizes are distributed primarily in the range of 0.1—0.5μm. During the formation of HMX/FOX-7 nano-cocrystals, the “low-temperature freezing” of the HMX/FOX-7 solution from liquid nitrogen and the formation of hydrogen bonding among HMX and FOX-7 have an significant influence on the formation of HMX/FOX-7 nano-cocrystals. The apparent thermal decomposition enthalpies of HMX/FOX-7 nanocrystals is significantly higher than that of the raw HMX and FOX-7, and increases with the increase of HMX content. The mechanical sensitivity of each HMX/FOX-7 nano-cocrystal is substantially reduced compared with that of the raw HMX. When the molar ratio of HMX and FOX-7 is 1:3, the prepared HMX/FOX-7 cocrystal has the lowest mechanical sensitivity, where the impact sensitivity is higher than 45J and the friction sensitivity is 288N.

Based on the application research background of large aircraft impact,the experimental research is conducted on the impact of flying object on a prestressed reinforced concrete target plate.The scaled samples equivalent to flying object and prestressed reinforced concrete target plates are designed using a geometric scaling ratio of 1:6.Finite element analysis software is used to construct the collision models and calculate the impact damage effects of two scaled samples with different structures on the target plate at different speeds.A physical loading test is conducted using an air cannon,and the critical penetration velocity of two scaled samples on 200mm thick prestressed reinforced concrete is obtained by comparing the test results with simulated results.This provides basic data for intuitive prediction/evaluation of the impact response and failure mode of prestressed reinforced concrete containment in nuclear power plants,and also provides design references and basis for prototype collision test schemes.

The temperature fluctuation and magnetic noise in the alkali-metal vapor cell are key factors that restrict the sensitivity improvement of spin-exchange relaxation-free atomic spin gyroscopes. To deal with these two issues, a laser heating method is proposed to perform non-magnetic heating for the vapor cell, thus fundamentally eliminating the magnetic noise, and the graphene films are deposited on the heating surface, and adjacent upper and lower surfaces of the vapor cell for photothermal conversion, thermal conduction, and stray-light interference avoidance. The combination of linear active disturbance rejection control (LADRC）and thermal management technology is used to improve the temperature control accuracy and stability of alkali-metal vapor cell. A linear active disturbance rejection controller based on temperature control system is designed. A thermal structure is designed and graphene film is selected in consideration of heat conduction, thermal convection and thermal radiation. An experimental platform was built for the temperature control system of alkali-metal vapor cell. The result shows that the temperature control accuracy of temperature control system of alkali-metal vapor cell using LADRC and thermal management technology is ±0.003 ℃, and the temperature control stability is 6 mK. This lays the foundation for improving the sensitivity of atomic spin gyroscopes in the future.

A hierarchical multi-agent collaborative decision-making method based on the actor-critic (AC) frameworkis proposed to address the issues of improper task allocation and weak decision consistency in the collaborative decision-making of multiple agents in complex operational environments. The proposed method divides the decision-making process into different levels and utilizes the AC framework to facilitate information exchange and decision coordination among the agents, thereby enhancing thedecision efficiency and combat effectiveness. At the higher level, the top-level agents formulate thetask decisions by decomposing and assigning overall tasks to the lower-level agents. At the lower level, the lower-level agents make action decisions based on subtasks and provide feedback to the higher level. Experimental results demonstrate that the proposed method performs well in various operational simulation scenarios, showcasing its potential to enhance themilitary operational collaborative decision-making capability.

The micro-reaction technology for the preparation of nitroaromatics, nitrate esters, nitroamines, and other energetic materials are overviewed. The existing preparation processes for these energetic materials by using micro-reaction technology are classified and described. The micro-reaction technology has the advantages of enhancing product yield and selectivity, improving mass and heat transfer efficiency, and reducing reaction time. The issues such as blockages in micro-reaction synthesis are also analyzed. Furthermore, this review explores the application of micro-reaction technology in the preparation of micro and nano energetic materials and composite energetic materials. The benefits of micro-reaction technology in controlling particle size and morphology and continuous preparation of energetic materials are emphasized. By summarizing the existing technical difficulties, it is pointed out that the combination of micro-reaction technology with numerical simulation, the optimal design of reaction and heat transfer structures, and the exploration of reaction mechanisms are the important research fields for the application of micro-reaction technology in the preparation of energetic materials. 80 References are attached.

Linear focusing fragment warhead makes the fragments disperse at an equal velocity and focus linearly by taking advantage of the design of charge generatrix and fragment arrangement, which can exert structural cutting damage to a target. In order to study the influence of structural parameters of linear focusing fragment warhead on the dispersion characteristics of fragments, the fluid-structure interaction (FSI) algorithm is used to numerically simulated the focusing process of fragments. The numerically simulated results reveal the linear focusing mechanism of linear focusing fragment warhead. The typical linear focusing process includes fragment driving stage, fragment focusing stage, focusing completion stage and fragment dispersion stage. The effects of warhead size, fragment arrangement, fragment mass and intersection velocity on the dispersion and spatial distribution characteristics of fragments are further obtained by numerical simulation. The results show that, with the increase in charge length from 0.3 m to 0.5 m, the standard deviation of fragment velocity increases from 125 m/s to 147 m/s, the focusing completion time is 490 μs, 585 μs and 590 μs, respectively, and the width of perforation dense distribution increases from 135 mm to 234 mm. When the fragment arrangement increases from 15 columnsto 18 columns, the standard deviation of fragment velocity increases from 117 m/s to 125 m/s, the focusing completion time is 470 μs and 490 μs, respectively, and the width of perforation dense distribution increases from 235 mm and 135 mm respectively. When the fragment mass increases from 4.08 g to 9.21 g, the standard deviation of fragment velocity decreases from 137 m/s to 125 m/s, the focusing completion time is 380 μs and 490 μs, and the width of perforation dense distribution is 156 mm and 135 mm, respectively. When the interaction speed increases from 0 m/s to 1 000 m/s, the focusing completion time is 490 μs, 480 μs and 469 μs, respectively, the width of perforation dense distribution increases from 135 mm to 138 mm, and the density of fragment distribution decreases from 640/m² to 630/m²with a rate of about 2%. The research results can provide guidance and reference for the design of focusing warhead.

Ballistics is one of the foundational disciplines in weapons science and technology,closely related to the development of weapons technology. With the rise and development of intelligent projectiles and rockets,the theory and technology of intelligent ballistics will be a major direction for the future development of exterior ballistics. Nevertheless,how to understand the concept,connotation,and functions of intelligent ballistics,as well as its differences from existing projectiles and rockets in terms of flight trajectories,the key technologies it relies on,the challenges involved,and the issues that should be considered for the subsequent development,are still under discussion. Based on the theory and technology of exterior ballistics and focusing on the future development of exterior ballistics,this article tends to analyze and organize the aforementioned issues with the aim of providing assistance for the future development of intelligent ballistics theory and technology. It should be noted that the development of intelligent ballistics theory and technology has introduced numerous new problems,concepts,terminologies and technologies for exterior ballistics,which require continuous exploration,refinement,and gradual perfection by researchers in the field of exterior ballistics through ongoing research. This article merely serves as a starting point,hoping to inspire more researchers in the field of exterior ballistics to engage in this area of study and gradually develop a theoretical framework.

Kinetic energy missile is a new type of anti-armor weapon that combines the effects of kinetic energy strike and armor penetration, but there is currently no relevant theoretical model available for reference regarding the load characteristics and influencing factors of impact process. The load characteristics of the impact process of kinetic energy missiles are studied. By considering the missile-target action behaviors in different velocity ranges, a calculation model for the impact load of kinetic energy missile body is established. The calculated results indicate that the impact load of missile is directly related to the geometric characteristics, impact velocity, density, strength, and other properties of missile. The change in the impulse of missile is relatively small at low velocity, but at high velocity, the rebound of the shattered mass significantly increases the impulse, and the impulse contribution of the shell accounts for a larger proportion of the impact impulse. The amplitude of impact load curve increases with the increase of shell strength and density, but the influence of density on the load waveform characteristics is more obvious. At the same velocity, the influence of shell strength on the momentum transfer factor of missile is relatively small, but the influence of shell density has a significant effect on it. At the same velocity, the influence of shell strength on the momentum transfer factor of missile is relatively small, while the shell density has a greater impact on it, The transfer factor curve shows a trend of increasing first and then decreasing with the increase in density.

Ducted-fan unmanned aerial vehicle(UAV)can realize take-off,landing and hovering,which has a simple and reliable structure and high safety coefficient.In view of the restricted take-off and landing environment,redundancy of folding wing mechanism and low aerodynamic efficiency of conventional water-air amphibious UAVs,a new dual ducted fan water-air amphibious trans-media UAV is designed.The fuselage is optimized with reference to underwater unmanned underwater vehicle(UUV)and UAV,and the tilting dual ducted fan power system is used.Based on the improved blade element momentum theory,the theoretical formula for calculating the lift of small ducted fan is derived.The structural vibration pattern of UAV as a whole under the mechanical physical field is analyzed,and the aerodynamic performance of the whole vehicle is verified by flow field finite element simulation.The analyzed results show that the calculated results of the improved small ducted fan lift calculation formula are basically consistent with the wind tunnel test results,with the maximum error between the two results is 4.5%,and the designed small ducted fan can provide 20% of additional lift with high aerodynamic efficiency.Through the modal analysis,it is found that the UAV fuselage structure is more stable,and the vibration pattern is reasonable.The wind tunnel test and the test flight verification of the ducted fan water-air amphibious UAV in different media are completed,which proves the feasibility of the UAV design scheme.

Imidazolium 2,4,5-trinitroimidazole was synthesized by nitration of 2,4,5-trinitroimidazole(2,4,5-TII)in different mass fractions(20%, 50%, 65% and 98%)of nitric acid using micro-channel reaction technology, respectively. The structure was characterized by fourier transform infrared spectroscopy(FT-IR), nuclear magnetic resonance spectroscopy(NMR), elemental analysis(EA)and melting point testing. Results show that by using micro-channel nitration reaction technology, the optimal process conditions for preparing imidazolium 2,4,5-trinitroimidazole from 2,4,5-TII are as follows: the molar ratio of 2,4,5-TII and fuming nitric acid is 1:20, the reaction time is 6 min, the reaction temperature is 70～72℃, and the yield is 21.8%. Compared with the conventional tank reactor process, the micro-channel reaction process has the advantages of shorter reaction time, lower dosage of nitration reagent, slightly lower reaction temperature and slightly higher yield. However, it can not completely avoid the occurrence of side-reaction of oxidation.

From the development trend of modern artillery and ammunition technology,the problems faced by the internal ballistics of artillery were analyzed. The development direction of internal ballistics theory and technology is mainly reflected in three aspects. The first aspect is to improve the combat effectiveness of conventional solid propellant artillery. The second aspect is to develop internal ballistics theory and control technology that is matched with the launch methods of special ammunition such as guided munitions. The third aspect is to study the internal ballistic theory and control technology of new energy artillery. On this basis,combined with the research status at home and abroad,several key issues were reviewed,proposing research strategies.

In order to overcome the question of large fluctuation of trajectory tracking accuracy due to complex external unknown interference in the trajectory tracking control process of six-freedom-degree quad-rotor UAV,a new-type cascaded double-closed-loop control strategy was proposed for velocity error,and position and attitude error. Firstly,the model predictive control(MPC)was used to project the velocity closed-loop controller,and the sparrow search algorithm(SSA)was applied to the rolling optimization process of MPC to obtain the feasible solution due to the fast convergence and strong robustness. In order to solve the large computation in MPC,sliding mode control(SMC)was used to design the dynamic controller according to position and attitude respectively. SMC is insensitive to external interference,robust and does not need accurate modeling,thus solving the problems of external uncertain interference and difficulty in accurately modeling UAV. The saturation function was used to replace the symbolic function to make the input of the actual system continuous,thus effectively reducing the high-frequency chattering phenomenon in SMC. Finally,the stability of the SSA-MPC controller was proved by Lyapunov stability theory. By the proposed method,the six-freedom-degree quad-rotor UAV can achieve high-precision trajectory tracking control under complex external unknown interference and uncertain parameters,and the trajectory tracking accuracy is obviously better than the UAV control system composed of traditional single controller. The proposed controller is effective for the trajectory tracking control of quad-rotor UAV under complex external unknown interference.

By comparing the differences in the physical and chemical properties, such as the enthalpy of formation and phase transition temperatures of the fluorinated/oxidized products of metal fuels, the characteristics and potential application advantages of fluorination energy release reactions in energetic systems were summarized. The research progress of composite energetic systems based on fluorinated oxidizers, including typical types and characteristics of fluorinated oxidants, as well as their applications in pyrotechnics, propellants, mixed explosives, and aluminum thermites has been reviewed. The research and development direction of the application of fluorine-containing oxidizers in composite energetic systems was prospected. It is pointed out that the systematic computational chemistry research on composite energetic systems based on different fluorine sources should be conducted to understand the thermodynamic and kinetic mechanisms of fluorination reactions and their structure-activity relationships at the atomic/molecular level. Furthermore, research should also be intensified on the fluorine transfer mechanism in combustion reactions and the interfacial fluorine infiltration mechanism under pre-ignition conditions. Based on this, new typical fluorine-containing oxidizers suitable for different scenarios should be developed from the view point of nano architectonics and reaction pathway design. Attached with 137 references.

To study the explosiveness of biomass fuels, TG-DTG thermogravimetric analysis was used to analyze the combustion performance and kinetic parameters of several common biomass fuels(straw, sawdust, peanut shells)and their mixtures. The microstructures of these fuels were analyzed using scanning electron microscopy(SEM). Additionally, an elemental analysis of the wood powder and peanut shell powder mixture was carried out using an elemental analyzer. Based on the elemental composition, the amount of oxygen required for its oxidation reaction was calculated, and an explosion test was subsequently conducted. The results showed that the mixed fuel(wood powder and peanut shell powder in a 1:1 mass ratio)exhibited high stable combustion characteristics, flammability index, and overall combustion performance. The activation energy was moderate, and the surface appeared porous and rough, with more free surfaces and a larger specific surface area, which facilitated combustion. In an experiment,40g of this mixed fuel was loaded into a steel pipe with a diameter of 40mm, a length of 200mm, and a wall thickness of 1.5mm, and filled with 5MPa oxygen. The mixture was successfully detonated by a No.8 electronic detonator without producing toxic gases. The steel pipe was blasted into fragments of different sizes, with most fragments measuring less than 50mm. The research results indicate that biomass fuel can exhibit explosiveness under certain conditions.