A complex multiple flame structure is formed during the combustion of AP/HTPB base bleed propellant. The AP monopropellant flame is concentrated in a thin zone above the burning surface of AP crystal to maintain self-sustained decomposition. Due to the low temperature near the burning surface, the diffusion between the decomposition products of AP and the pyrolysis products of HTPB occurs, and a partly pre-mixed diffusion flame structure-leading edge flame (LEF) is formed. The effects of pressure, chemical reaction rate and AP particle size on diffusion flame structure in the range from 20 atm to 100 atm are discussed. The Peclet number increases from 6.64 at 20 atm to 21.91 at 100 atm when AP particle size is 140 μm. The high temperature zone is blown away from the burning surface because the convective transport rate increases with the increase in Peclet number. The chemical reaction rate is enhanced and the diffusion mixing is inhibited as Damkohler number increases. The chemical heat release is more concentrated and the chemical reaction zone becomes narrow when Damkohler number changes from 330 at 20 atm to 4700 at 100 atm. When AP particle diameter is decreased to 60 μm, the diffusion time scale is reduced due to the reduced diffusion length scale. So the diffusion mixing is enhanced and a more pre-mixed flame is formed. The burning rate increases because the more pre-mixed heat release increases the heat feedback to the HTPB binder. © 2013 China Ordnance Society

A rough set probabilistic data association (RS-PDA) algorithm is proposed for reducing the complexity and time consumption of data association and enhancing the accuracy of tracking results in multi-target tracking application. In this new algorithm, the measurements lying in the intersection of two or more validation regions are allocated to the corresponding targets through rough set theory, and the multi-target tracking problem is transformed into a single target tracking after the classification of measurements lying in the intersection region. Several typical multi-target tracking applications are given. The simulation results show that the algorithm can not only reduce the complexity and time consumption but also enhance the accuracy and stability of the tracking results. © 2013 China Ordnance Society

In order to study the propagation mechanism of continuous rotating detonation wave, the H2/air continuous rotating detonation engine ignited by tangentially installed H2/O2 pre-detonation tube is studied experimentally using a tilt slot injector structure. The experimental results show that the stable rotating detonation wave can be gained successfully with the equivalent ratio of 0.93. The propagation frequency and velocity of rotating detonation wave range from 5200 to 5500 Hz and from 1518.5 to 1606.1 m/s, respectively. Three propagation modes, such as rotation, reversal and bifurcation, of detonation wave are verified through the analysis of propagation mechanism of rotating detonation wave. © 2013 China Ordnance Society

The dynamic fracture behaviors of the extruded 2024-T4 and 7075-T6 aluminum alloys are investigated by using an instrumented drop tower machine. The specimens are made from a 25 mm diameter extruded circular rod. The dynamic three-point bending tests of each alloy are carried out at different impact velocities. The initiation fracture toughness and average propagation fracture toughness of 2024-T4 and 7075-T6 are determined at different loading rates. The results show that both the initiation toughness and the propagation toughness increase with the loading rate. Further, the difference between the fracture toughness behaviors of 2024-T4 and 7075-T6 is found to be dependent on the variation of fracture mechanism. The comprehensive fractographic investigations of the fracture surfaces clearly demonstrate that the fracture mode of 2024-T4 is predominantly transgranular fracture with high density small-sized dimples, and the fracture mode of 7075-T6 is mainly intergranular fracture with many intermetallic particles in the bottom of voids located in the fracture surface. © 2013 China Ordnance Society

The design, modeling, and simulation of a micro electrical switch for fuze are presented. It consists of spring–mass system with zigzag slot in mass, latching and electrical connection mechanism and movement-limit mechanism. The switch keeps off-state until it is subjected to an acceleration when fuze is launched normally. The acceleration is simulated as half-sine pulse with specific amplitude and duration. The dynamics model of the switch is studied. Based on zigzag slot in mass, the methods used for recognizing acceleration load are established and analyzed according to the dynamics theory. Two typical half-sine accelerations are loaded on the switch in simulation. The simulation results are in accordance with those of theoretical analysis. The inertial response characteristics of the switch can ensure that the fuze power supply and circuit are connected safely and reliably. © 2013 China Ordnance Society

The mechanical behaviors of polytetrafluoroethylene (PTFE) in compressive test performed at different strain rates ranging from 10−2 s−1 to 103 s−1 are studied. The experimental results show that the yield strength increases with the increase in strain rate and exhibits a bilinear dependence on the logarithms of the stain rates, but the yield strain decreases with the increase in strain rate. Based on the mathematical model proposed by Nunes and the bilinear relationship between yield strength and strain rate, a modified constitutive model which can describe its complex non-linear mechanical behavior is proposed. The experimental results are in a good agreement with the predicted results of model within 40% of strain. © 2013 China Ordnance Society

1553B avionics data bus network may fail due to vibration, temperature, humidity or human error. Therefore, the research on detection technology of 1553B avionics data bus network is an important subject. The key technologies are studied by analyzing the possible faults of the network, including four-wire DC resistance measurement method for conductors-to-shield short test and stub continuity test, equivalent impedance measurement of coupling transformer for main bus continuity test, polarity reversal test base on duty ratio measurement, attenuation measurement base on coupler model, and data path integrity test base on bit error rate calculation. Finally, the implementation methods of key technologies are researched, a portable integrated automatic test system of 1553B data bus network is constructed based on PC104 computer, and the hardware configuration and test process are especially designed. © 2013 China Ordnance Society

A one-dimensional pipe flow model of single-cylinder diesel engine is established to investigate the intake and exhaust flow characteristics of diesel engine in the condition of high power density (HPD). A space-time conservation element and solution element (CE/SE) method is used to derive the discrete equations of the partial differential equation for the intake and exhaust systems. The performance parameters of diesel engine with speed of 2100 r/min are simulated. The simulated results are in accordance with the experimental data. The effect of increased power density on charging coefficient is analyzed using a validated model. The results show that the charging coefficient is slowly improved with the increase in intake pressure, and is obviously reduced with the increase in engine speed. © 2013 China Ordnance Society

Colorless and transparent thin films of collodion are prepared on silicon wafers and K9 optical glass substrates by using spin-coating technique. The visible light transmittance, IR absorption spectra and optical constants of collodion thin film are measured by UV-3501 Spectrophotometer, Fourier transform infrared spectrometer (FTIR) and spectroscopic ellipsometry. The measured results show that its average visible light transmittance is 91.9%, and its average infrared absorptivity is better than 0.69/um. In the visible light region, the refractive index of collodion thin film changes in the range of 1.5–1.53, which accords with normal dispersion. The collodion films are etched using oxygen gas plasma. The surface morphology and thickness of etched thin film are measured by the polarizing microscope and MP-100S thickness measurement system, respectively. The results show that the collodion thin film is etched out in the oxygen gas plasma. © 2013 China Ordnance Society

Nozzle damping is one of the most important factors in the suppression of combustion instability in solid rocket motors. For an engineering solid rocket motor that experiences combustion instability at the end of burning, a wave attenuation method is proposed to assess the nozzle damping characteristics numerically. In this method, a periodic pressure oscillation signal which frequency equals to the first acoustic mode is superimposed on a steady flow at the head end of the chamber. When the pressure oscillation is turned off, the decay rate of the pressure can be used to determine the nozzle attenuation constant. The damping characteristics of three other nozzle geometries are numerically studied with this method under the same operating condition. The results show that the convex nozzle provides more damping than the conical nozzle which in turn provides more damping than the concave nozzle. All the three nozzles have better damping effect than that of basic nozzle geometry. At last, the phase difference in the chamber is analyzed, and the numerical pressure distribution satisfies well with theoretical distribution. © 2013 China Ordnance Society

A spatial color-mixing model based on tricolor angular frequencies is proposed in consideration that the design theory falls behind the application of digital camouflage pattern. The model is based on Fourier transform and Gaussian low-pass filter (LPF). In the model, the tricolor angular frequencies are introduced to the spatial frequency response function of human color vision, and the effects of atmospheric attenuation and air screen brightness on color mixture are considered. The field test shows that the model can simulate the color-mixing process in the aspects of color-mixing order, and shape and position of color-mixing spot. But the color-mixing spot color is not perfect, which can be improved by optimizing the atmospheric parameters and tricolor cut-off angular frequencies. The model provides a tool for the research on digital camouflage pattern. © 2013

The interaction and compatibility between diaminoazofuraz (DAAzF) and some energetic materials are studied by using pressure differential scanning calorimetry (DSC) method. The energetic materials include cyclotetramethylenetetranitramine (HMX), cyclotrimethylenetrinitramine (RDX), nitrocellulose (NC), nitroglycerine (NG), 125/100–NC/NG mixture (NC + NG), N-nitrodihydroxyethylaminedinitrate (DINA), aluminum powder (Al), and 3,4-dinitrofurzanfuroxan (DNTF). The results show that there are obvious interactions between DAAzF and DNTF, DINA, HMX or RDX, while weak interactions between DAAzF and NC, NG, NC + NG or Al. According to the evaluated standard of compatibility, the binary systems of DAAzF with NC, NG, NC + NG and Al are compatible, the binary system of it with RDX is slightly sensitive, the binary systems of it with HMX and DINA are sensitive, and the binary system of it with DNTF is hazardous. © 2013 China Ordnance Society

The casting-solid extrusion forging plus semi-solid partial remelting route is used to improve the properties of AZ31 magnesium alloy products. The effect of remelting temperature and holding time on the microstructure of AZ31 magnesium alloy is studied. Furthermore, the properties of AZ31 magnesium alloy components produced by the casting-solid extrusion forging plus partial remelting route are examined. The results show that the AZ31 components have very good smooth surface and are formed completely. The increases in holding time and remelting temperature result in the formation of spheroidal grains surrounded by liquid phases. The best combination of properties of thixoforged alloy is 290 MPa of tensile strength, 220 MPa of yield strength and 10% of percentage elongation. © 2013 China Ordnance Society

The matters of equipment optimization development are usually discrete, fuzzy and non-quantitative. It is difficult directly to optimize the equipment development with a mathematical model. A set of methods for designing the equipment optimization development with six dimensions and eight main elements is established based on the theory and method of standardization. The top-tier design space of systematic development of equipment is built up by the relations of basic models, series and model spectrums. The relations of time and space for equipment optimization development are established. The design processes of a six dimension systematic space are expounded. The connotation of each plan in the main system space is analyzed. A design method for an entire equipment is established with standardization theory. The coordinating design methods of equipment technical system and the optimization design methods of equipment integration are discussed. The design methods for universalization and serialization of components and parts are established. The design methods of equipment optimization development highlight the relations of the basic model of platform, the serialization of platform basic models, the modularization of equipment functions, the model spectrum of variant equipment, and the universalization and serialization of components and parts. © 2013 China Ordnance Society

The electronic structures, elastic properties and thermodynamics of MgZn2, Mg2Y and Mg2La have been determined from the first-principle calculations. The calculated heats of formation and cohesive energies show that Mg2La has the strongest alloying ability and structural stability. The structural stability mechanism is also explained through the electronic structures of these phases. The ionicity and metallicity of the phases are estimated. The elastic constants are calculated; the bulk moduli, shear moduli, Young's moduli, Poisson's ratio value and elastic anisotropy are derived; and the brittleness, plasticity and anisotropy of these phases are discussed. Gibbs free energy, Debye temperature and heat capacity are calculated and discussed. © 2013 China Ordnance Society

Comments are given on the various physical definitions of the force constant of propellant. As there are more or less defects in these definitions, two new definitions are presented to reflect the physical essence of propellant force more perfectly and could well compatible with the mathematical expression. © 2013 China Ordnance Society

Mechanical properties and corrosion resistance of Si3N4 films are studied by using different experiment parameters, such as plasma enhanced chemical vapor deposition (PECVD)RF power, ratio of reaction gas, reaction pressure and working temperature. The etching process of Si3N4 is studied by inductively coupled plasma (ICP) with a gas mixture of SF6 and O2. The influence of the technique parameters, such as ICP power, DC bias, gas composition, total flow rate, on the etching selectivity of Si3N4/EPG533 which is used as a mask layer and the etching rate of Si3N4 is studied, in order to get a better etching selectivity of Si3N4/EPG533 with a faster etching rate of Si3N4. The optimized process parameters of etching Si3N4 by ICP are obtained after a series of experiments and analysis. Under the conditions of the total ICP power of 250 W, DC bias of 50 W, total flow rate of 40 sccm and O2 composition of 30%, the etching selectivity of 2.05 can be reached when Si3N4 etching rate is 336 nm/min. © 2013 China Ordnance Society

Recognizing the underwater targets by the radiated noise information is one of the most significant subjects in the area of underwater acoustics. A novel recognition approach which consists of the algorithms of Bark-wavelet analysis, Hilbert–Huang transform and support vector machine is proposed based on the theory of auditory perception. The performance of the proposed method is validated by comparing with traditional method and evaluated by the recognition experiments for SNRs of 0 dB, 5 dB, 10 dB, 15 dB and 20 dB. The results show that the average recognition rate of the method is above 88% and can be increased by 0.75%–6.25% under various SNR conditions compared to the baseline system. © 2013 China Ordnance Society

A series of impact tests of sandwich samples were completed using a large-diameter split Hopkinson pressure bar (SHPB) device at different velocities. The interlayer is made of foam concrete, loess or sand. The stress peak value decay, energy decay and waveform dispersion characters are studied by comparing incident waves with transmission waves. The tests indicate that the foam concrete has the best capabilities of shock resistance and energy absorption, the loess comes second, and the sand takes third place. © 2013 China Ordnance Society

The structures, infrared spectra, and cation stability of seven 5,5′-azotetrazolate nonmetallic salts are investigated by using B3LYP method with 6-311+G (d) basis set. The salts are guanidinium (GZT), aminoguanidinium (AGZT), diaminoguanidinium (DAGZT), triaminoguanidinium (TAGZT), azidoformamidinium (AFZT), ammonium (AZT), and hydrazinium (HZT). The calculated results indicate that the carbon and nitrogen atoms of the cations in seven nonmetallic salts are characterized to be sp2 hybrid atoms, and the ranges of characteristic absorption peaks in IR spectra of the seven nonmetallic salts are approximative consistent. All their cations are stable and their stabilities decrease with the increase in their nitrogen contents. © 2013

Elastic wave on seafloor caused by low frequency noise radiated from ship is called ship seismic wave which can be used to identify ship target. In order to analyze the wave components and the propagating properties of ship seismic wave, the numerical calculation of synthetic seismograms on seafloor aroused by a low frequency point sound source is carried out using a wave number integration technique combined with inverse Fourier transform. According to the numerical example of hard seafloor, the time series of seismic wave on seafloor are mostly composed of interface waves and normal mode waves. Each normal mode wave has a well-defined low cut-off frequency, while the interface wave doesn't have. The frequency dispersion of normal mode wave is obvious when frequency is lower than 100 Hz, while the interface wave is dispersive only in the infra-sound frequency range. The time series of seismic wave is dominated by the interface wave when the source frequency is less than the minimal cut-off frequency of normal mode wave. © 2013 China Ordnance Society

In order to study and apply the penetration performance of jetting penetrator charge at long stand-off distance, three jetting penetrator charges (JPC), including spherical cone liner, truncated wide-angle liner and spherical segment liner, are designed. The numerical simulation analysis of the formation, elongation and penetration processes of rod-like jet is conducted by using LS-DYNA software. And the penetrating test is carried out at long stand-off distance. The test results show that the rod-like jet formed by the optimized spherical segment liner can pierce through a 90 mm thick 45# steel target at 20 charge diameters (CD) Stand-off distance when the charge detonation mode is a central point initiation, and the penetration depth can be up to 1.6CD. It is concluded that, at 20 CD stand-off distance, the penetration performance of JPC with spherical segment liner is the best, that of truncated wide-angle liner takes second place, and that of spherical cone liner is the worst. © 2013 China Ordnance Society

The Lorentz force generated by electromagnetic field on the surface of the cylinder in the electrolyte solution may modify the structures of the flow boundary layer effectively. The transient control process of Lorentz force is investigated experimentally for lift amplification and vibration suppression. The experiments are conducted in a rotating annular tank filled with a low-conducting electrolyte. A cylinder with an electro-magnetic actuator is placed into the electrolyte. The lift force of cylinder is measured using the strain gages attached to a fixed beam, and the flow fields are visualized by the dye markers. The results show that the upper vortex on the cylinder is suppressed, and the wake becomes a line and leans to the lower side under the action of upside Lorentz force while the lower vortex on the cylinder is suppressed and limited in a small region. Therefore, the value of lift increases with the variation of flow field. However, the vortexes on the cylinder are suppressed fully under the action of symmetrical Lorentz force which leads to the suppression of lift oscillation and then the vibration of cylinder are suppressed fully. © 2013 China Ordnance Society

A metal foil spark gap switch is fabricated by using the magnetron sputtering deposition technology and the standard microelectronic technology. The switch consists of two main electrodes and a trigger electrode. Stylus profiler is used to measure the distance between the main electrode and the trigger electrode. The discharge characteristics of the metal foil spark gap switch are discussed. The switch has short delay time and low time jitter. When it is fired by a conventional capacitive discharge unit (CDU), the firing circuit has low inductance and resistance. Because of its low profile structure, it can be easily integrated with the bridge foil used in a conventional exploding foil initiator system (EFIS). © 2013 China Ordnance Society

This article presents a comprehensive review of recent progress of research dedicated to structure- and size-controlled micro/nano-energetic materials. The development of the construction strategies for achieving zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) micro/nanostructures from energetic molecules is introduced. Also, an overview of the unique properties induced by micro/nanostructures and size effects is provided. Special emphasis is focused on the size-dependent properties that are different from those of the conventional micro-sized energetic materials, such as thermal decomposition, sensitivity, combustion and detonation, and compaction behaviors. A conclusion and our view of the future development of micro/nano-energetic materials and devices are given. © 2013 China Ordnance Society

Microcellular propellants show a vast applicable prospect due to their special shell-pore structure. The effects of saturation pressure and desorption time on skin thickness were studied. The skin thickness is observed and measured using scanning electron microscope (SEM). The results show that the skin thickness decreases when saturation pressure increases from 15 MPa to 30 MPa. In contrast, the skin thickness increases as the desorption time changes from 2 min to 20 min. Therefore, the microcellular propellants with adjustable skin thickness can be obtained under the variable process conditions such as saturation pressure and desorption time. © 2013

Compared with the one-dimensional trajectory correction technology which adjusts longitudinal range, not only does the two-dimensional trajectory correction technology adjust the force in velocity direction, but also need to modulate the lateral force or trajectory (perpendicular to the vertical plane of fire direction). Therefore, the structure of control cabin of two-dimensional trajectory correction projectile (TDTCP) is more complicated than that of one-dimensional trajectory correction projectile (ODTCP). To simplify the structure of control cabin of TDTCP and reduce the cost, a scheme of adding a damping disk to the control cabin of ODTCP has been developed recently. The damping disk is unfolded at the right moment during its flight to change the ballistic drift of spin stabilized projectile. For this technical scheme of TDTCP, a fast and accurate impact point prediction method based on Extended Kalman Filter was presented. An approximate formula for predicting the ballistic drift and trajectory correction quantity was deduced. And the lateral correction capability for different fire angles and its influencing factors were analyzed. All the work is valuable for further research. © 2013 China Ordnance Society

The investigation of novel signal processing tools is one of the hottest research topics in modern signal processing community. Among them, the algebraic and geometric signal processing methods are shown to be one of the most powerful tools for the representation of the classical signal processing method. In this paper, we provide an overview of recent contributions pertaining to the algebraic and geometric signal processing. Specifically, the paper focuses on the mathematical structures behind the signal processing by emphasizing the algebraic and geometric structure of the signal processing. The two major topics were discussed. First, the classical signal processing concepts are related to the algebraic structures, and the recent results associated with the algebraic signal processing theory are introduced. Second, the recent progress of the geometric signal and information processing representations associated with the geometric structure are discussed. From these discussions, it is concluded that the research on the algebraic and geometric structure of signal processing can help the researchers to understand the signal processing tools deeply, and also help us to find novel signal processing methods in signal processing community. Its practical applications are expected to grow significantly in years to come, given that the algebraic and geometric structure of signal processing offer many advantages over the traditional signal processing. © 2013 China Ordnance Society

The research progress of swarm robotics is reviewed in details. The swarm robotics inspired from nature is a combination of swarm intelligence and robotics, which shows a great potential in several aspects. First of all, the cooperation of nature swarm and swarm intelligence are briefly introduced, and the special features of the swarm robotics are summarized compared to a single robot and other multi-individual systems. Then the modeling methods for swarm robotics are described, followed by a list of several widely used swarm robotics entity projects and simulation platforms. Finally, as a main part of this paper, the current research on the swarm robotic algorithms are presented in detail, including cooperative control mechanisms in swarm robotics for flocking, navigating and searching applications. © 2013 China Ordnance Society

Intra-body communication (IBC) is a technology using the human body as a transmission medium for electrical signals. Compared with the short distance wireless communication technologies, it has several novel characteristics. The modeling, simulation and implement of intra-body communication are reviewed. Firstly, the transfer function of the galvanic coupling IBC was deduced, and the in vivo measurements results and the corresponding mathematical simulations results based on the proposed transfer function are discussed. Secondly, a finite-element method for modeling the whole human body is introduced, and simulations results of the galvanic coupling IBC based on the whole human body and the corresponding in vivo measurement results are discussed. Finally, the implement methods of the intra-body communication as well as a novel IBC system based on Mach–Zehnder EO modulator are introduced and analyzed, while some conclusions are achieved. © 2013

A fiber Bragg grating (FBG) geophone and a surface seismic wave-based algorithm for the direction of arrival (DOA) are described. The operational principle of FBG geophone is introduced and illustrated with systematic experimental data, demonstrating an improved FBG geophone with many advantages over the conventional geophones. An innovative, robust, and simple algorithm is developed for obtaining the bearing information on the seismic events, such as people walking, or vehicles moving. Such DOA estimate is based on the interactions and projections of surface-propagating seismic waves generated by the moving personnel or vehicles with a single tri-axial seismic sensor based on FBGs. Of particular interest is the case when the distance between the source of the seismic wave and the detector is less than or comparable to one wavelength (less than 100 m), corresponding to near-field detection, where an effective method of DOA finding lacks. © 2013 China Ordnance Society

This paper proposes an adaptive neural control (ANC) method for the coupled nonlinear model of a novel type of embedded surface morphing aircraft which has a tiltable V-tail. A nonlinear model with six-degrees-of-freedom is established. The first-order sliding mode differentiator (FSMD) is applied to the control scheme to avoid the problem of “differential explosion”. Radial basis function neural networks are introduced to estimate the uncertainty and external disturbance of the model, and an ANC controller is proposed based on this design idea. The stability of the proposed ANC controller is proved using Lyapunov theory, and the tracking error of the closed-loop system is semi-globally uniformly bounded. The effectiveness and robustness of the proposed method are verified by numerical simulations and hardware-in-the-loop (HIL) simulations. © 2022 China Ordnance Society

Based on the high positioning accuracy, low cost and low-power consumption, the ultra-wide-band (UWB) is an ideal solution for indoor unmanned aerial vehicle (UAV) localization and navigation. However, the UWB signals are easy to be blocked or reflected by obstacles such as walls and furniture. A resilient tightly-coupled inertial navigation system (INS)/UWB integration is proposed and implemented for indoor UAV navigation in this paper. A factor graph optimization (FGO) method enhanced by resilient stochastic model is established to cope with the indoor challenging scenarios. To deal with the impact of UWB non-line-of-sight (NLOS) signals and noise uncertainty, the conventional neural net-works (CNNs) are introduced into the stochastic modelling to improve the resilience and reliability of the integration. Based on the status that the UWB features are limited, a ‘two-phase’ CNNs structure was designed and implemented: one for signal classification and the other one for measurement noise prediction. The proposed resilient FGO method is tested on flighting UAV platform under actual indoor challenging scenario. Compared to classical FGO method, the overall positioning errors can be decreased from about 0.60 m to centimeter-level under signal block and reflection scenarios. The superiority of resilient FGO which effectively verified in constrained environment is pretty important for positioning accuracy and integrity for indoor navigation task. © 2022 China Ordnance Society

Gradiently denitrated gun propellant (GDGP) prepared by a “gradient denitration” strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant. Currently, the preparation of GDGP employed a tedious two-step method involving organic solvents, which hinders the large-scale preparation of GDGP. In this paper, GDGP was successfully prepared via a novelty and environmentally friendly one-step method. The obtained samples were characterized by FT-IR, Raman, SEM and XPS. The results showed that the content of nitrate groups gradiently increased from the surface to the core in the surface layer of GDGP and the surface layer of GDGP exhibited a higher compaction than that of raw gun propellant, with a well-preserved nitrocellulose structure. The denitration process enabled the propellant surface with regressive energy density and good progressive burning performance, as confirmed by oxygen bomb and closed bomb test. At the same time, the effects of different solvents on the component loss of propellant were compared. The result showed that water caused the least component loss. Finally, the stability of GDGP was confirmed by methyl-violet test. This work not only provided environmentally friendly, simple and economic preparation of GDGP, but also confirmed the stability of GDGP prepared by this method. © 2023 China Ordnance Society

The weapon transportation support scheduling problem on aircraft carrier deck is the key to restricting the sortie rate and combat capability of carrier-based aircraft. This paper studies the problem and presents a novel solution architecture. Taking the interference of the carrier-based aircraft deck layout on the weapon transportation route and precedence constraint into consideration, a mixed integer formulation is established to minimize the total objective, which is constituted of makespan, load variance and accumulative transfer time of support unit. Solution approach is developed for the model. Firstly, based on modeling the carrier aircraft parked on deck as convex obstacles, the path library of weapon transportation is constructed through visibility graph and Warshall-Floyd methods. We then propose a bi-population immune algorithm in which a population-based forward/backward scheduling technique, local search schemes and a chaotic catastrophe operator are embedded. Besides, the random-key solution representation and serial scheduling generation scheme are adopted to conveniently obtain a better solution. The Taguchi method is additionally employed to determine key parameters of the algorithm. Finally, on a set of generated realistic instances, we demonstrate that the proposed algorithm outperforms all compared algorithms designed for similar optimization problems and can significantly improve the efficiency, and that the established model and the bi-population immune algorithm can effectively respond to the weapon support requirements of carrier-based aircraft under different sortie missions. © 2023 China Ordnance Society

Thermite films are typical energetic materials (EMs) and have great value in initiating explosive devices. However, research in thermite film preparation is far behind that of research in thermite powders. Electrophoretic deposition (EPD) is an emerging, rapid coating method for film fabrication, including of energetic composite films. In this work, a polytetrafluoroethylene (PTFE)/Al/CuO organic-inorganic hybrid energetic film was successfully obtained using the above method for the first time. The addition of lithocholic acid as a surfactant into the electroplating suspension enabled PTFE to be charged. The combustion and energy release were analyzed by means of a high-speed camera and differential scanning calorimetery (DSC). It was found that the combustion process and energy release of PTFE/Al/CuO were much better than that of Al/CuO. The main reason for the excellent combustion performance of the hybrid PTFE/Al/CuO system was that the oxidability of PTFE accelerated the redox reaction between Al and CuO. The prepared PTFE/Al/CuO film was also employed as ignition material to fire a B–KNO3 explosive successfully, indicating considerable potential for use as an ignition material in micro-ignitors. This study sheds light on the preparation of fluoropolymer-containing organic-inorganic hybrid energetic films by one-step electrophoretic deposition. © 2021 China Ordnance Society

In order to pursue good crushing load uniformity and enchance energy absorption efficiency of conventional honeycombs, a kind of bio-inspired hierarchical honeycomb model is proposed by mimicking the arched crab shell structures. Three bio-inspired hierarchical honeycombs (BHHs) with different topologies are designed by replacing each vertex of square honeycombs with smaller arc-shaped structures. The effects of hierarchical topologies and multi-material layout on in-plane dynamic crushings and absorbed-energy capacities of the BHHs are explored based on the explicit finite element (FE) analysis. Different deformation modes can be observed from the BHHs, which mainly depend upon hierarchical topologies and impact velocities. According to energy efficiency method and one-dimensional (1D) shock theory, calculation formulas of densification strains and plateau stresses for the BHHs are derived to characterize the dynamic bearing capacity, which is consistent well with FE results. Compared with conventional honeycombs, the crushing load efficiency and energy absorption capacity of the BHHs can be improved by changing the proper hierarchical topology and multi-material layout. These researches will provide theoretical guidance for innovative design and dynamic response performance controllability of honeycombs. © 2023 China Ordnance Society

This study elaborates on the effects of matrix rigidity on the high-velocity impact behaviour of UHMWPE textile composites using experimental and numerical methods. Textile composite samples were manufactured of a plain-weave fabric (comprising Spectra® 1000 fibres) and four different matrix materials. High-velocity impact tests were conducted by launching a spherical steel projectile to strike on the prepared samples via a gas gun. The experimental results showed that the textile composites gradually changed from a membrane stretching mode to a plate bending mode as the matrix rigidity and thickness increased. The composites deformed in the membrane stretching mode had higher impact resistance and energy absorption capacity, and it was found that the average energy absorption per ply was much higher in this mode, although the number of broken yarns was smaller in the perforated samples. Moreover, the flexible matrix composites always had higher perforation resistance but larger deformation than the rigid matrix counterparts in the tested thickness and velocity range. A novel numerical modelling approach with enhanced computational efficiency was proposed to simulate textile composites in mesoscale resolution. The simulation results revealed that stress and strain development in the more rigid matrix composite was localised in the vicinity of the impact location, leading to larger local deformation and inferior perforation resistance. © 2022 China Ordnance Society