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Ballistic gelatin is used as a stimulant for human tissue in the experimental study of temporary cavity which is an important factor of ballistic injury. To study the motion of temporary cavities, the steel spheres with diameters of 3 mm, 4 mm and 4. 8 mm are fired into the gelatin blocks at 650 ~ 1 000 m/s in the experiments. The movement of temporary cavity is recorded by a high speed camera. The sine motion of the cavity wall is deducted based on the displacement field assumption and the elastic deformation assumption of gelatin. The empirical relations between amplitude and energy, and frequency and energy are established using the experimental data while a penetration model of spherical fragments in gelatin is built. The model is used to predict the temporary cavity for a 5. 2 mm tungsten sphere penetrating into gelatin at 800 m/s. The predicted results are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

The two-phase flow mathematic models are developed for gas generator with central igniter tube. The one-dimensional two-phase model is used for the ignition of central igniter tube, and the two-dimensional two-phase model is used for the energy release of tubular gas generator. The coupling function of two tubes is established through exchange between gas and solid. The interior ballistic simulation software is programmed by Mac Cormack two-step scheme and is used to calculate the gas generator. The calculated results well accord with the test results, which proves that the model is right and provides important theory foundation to structure design and optimization on gas generator with central igniter tube. Meanwhile, the energy releasing course is analyzed based on the simulation results. The result shows that the uniform ignition condition is the precondition of gas generator releasing energy steadily. The ignition energy released uniformly could ensure the reliable burning of powders in gas generator and the release of controlled energy. [ABSTRACT FROM AUTHOR]

The warship continues to move after the trajectory correction projectile is fired from shipborne gun, and the shipborne radar for trajectory measurement also continue to move and sway, and so the relative trajectory measured by radar need to be transformed into the ballistic reference frame which takes the gun muzzle as an origin during firing. The precision of transformed ballistic coordinates is influenced by the warship fluctuation and the errors of radar measuring, warship sway angles, velocity and course bearing. In order to quantify the influence of every error on the precision of ballistic coordinates, a model of precision of ballistic coordinates was set up and simulated, and some data about the influence of warship fluctuation and the errors of radar measuring, warship sway angles, velocity and course bearing on the precision of ballistic coordinates were got. [ABSTRACT FROM AUTHOR]

To get the surface temperature characteristics of projectile flying at high rotational speed, based on the six degree of freedom (6-DOF) rigid body trajectory model, the heat balance equations were established by using node thermal network method. With the heat exchange theory of flow around a cylinder, the influence of rotation was considered for the calculation of aerodynamic heating. The temperature field distribution under the control of trajectory data and airflow properties was obtained by solving the trajectory equations and the heat balance equations simultaneously. Finally, the factors which have impact on the surface average temperature field, including launching velocity, initial rotational speed, launching angle and airflow temperature, were also studied. The results show that the surface temperature increases with launching velocity non-linearly. The temperature gradient is inversely proportional to the distance from the warhead. The bigger the initial rotational speed is, the higher the peak temperature and the rate of temperature change are. The higher the airflow temperature is, and the smaller the launching angle is, the higher the average temperature is. [ABSTRACT FROM AUTHOR]

A novel 2-DOF ammunition coordinator structure scheme is proposed, and the controlled dynamics behavior of the coordinator is studied by considering the influence of the random vibration of its installation base. The random vibration of base is treated as one kind of external disturbance forces acting on the coordinator, and the action of the coordinator on the base is negligible. On the assumption that the external disturbance force and the control force are bounded, a nonlinear control algorithm and the structure-control coupling dynamics equations of the coordinator are established based on the second kind La-grange equations and a special implicitly given Lyapunov function. The dynamics equations are solved by a numerical algorithm based on Newton's method and the Runge-Kutta method. The simulation result shows that the proposed 2-DOF ammunition coordinator can be used to realize the accurate coordination and positioning control of the ammunitions. [ABSTRACT FROM AUTHOR]

In order to explore the bullet proof mechanism of ceramic/steel composite armor, the ballistic impact experiment was carried out to study the dynamic response of ceramic/steel composite armor subjected to the impact of high speed fragments. The damages of projectile, ceramic and steel back plate were described physically and analyzed phenomenologically. The damage modes of ceramic and steel back plate were determined. The energy transformation during the ballistic penetration and the bullet proof performance of the ceramic/ship steel composite armor were analyzed. The results show that the conical crash is a main damage mode of ceramic under the impact of high speed fragments. And the main macro cracks are radial, ring and conical cracks which extend outward at about 65° angle included between the conical crack and the initial surface normal. Besides there are the inverse conical cracks extended outward at angle of 65° to the back surface normal. The deformation range, destructiveness and damage mode of the back plate have great different from those of ship steel target. The deformation mode of the backing plate is bulging-dishing when the impact velocity is below the ballistic limit. When the impact velocity exceeds the ballistic limit, the back plate has 3 damage modes, i. e. shearing damage, dishing-shearing-petaloid damage and dishing-petaloid damage, as the relative thickness of ceramic increases. In the penetration process of light ceramic/metal composite armor, the kinetic energy of projectile is mainly dissipated in the deformation and damage of projectile and back plate. When the velocity of the penetrator is about ballistic limit, the energy dissipated in projectile and back plate damages varies with the relative thickness of ceramic. But the total energy dissipated in these facets occupies more than 90% of initial kinetic energy of the projectile, and the energy dissipated in the fragmentation of ceramic and the ejecting kinetic energy of ceramic fragments occupies less than 10% of its initial kinetic energy. [ABSTRACT FROM AUTHOR]

Probability of perforation ( POP) curve is a constructive method to estimate the ballistic performance. It can be used to estimate the low velocity at smaller penetration probability. POP curves have potential and promising application in body armor design. For this purpose, the performance of UH- MWPE unidirectional layers (PE armor) against 7.62 mm type 51 pistol bullet was investigated. POP curves was established by logistic function and binary logistic regression. v50 (velocity with 50% penetration probability) and v05 (velocity with 5% penetration probability) of PE armor were derived from POP curves. v50 was 592 m/s determined by both methods, while v05 was 538 m/s and 514 m/s, respectively. The results indicate that the regression method is more suitable for the estimation of velocity at low penetration probability. The difference between the two POP curves was discussed. [ABSTRACT FROM AUTHOR]

Low-velocity ballistic experiments were carried out to study the perforation-resistant mechanisms of warship topside composite armor system, which was simulated by composite laminates at the front and homogeneous steel plates at the back. Failure modes and energy absorbing mechanisms were investigated and the influence of the area density of front composite armors on total perforation resistance of combined targets was analyzed. Based on the experiments, an equation was obtained to predict the residual velocities in the case of low-velocity perforation of combined targets by hemispherical-nosed projectiles according to the failure modes of the targets. The results show that under low velocity perforation, combined targets mainly exhibit local damage. A few amounts of fiber at the impact side of front composite armor are sheared by the projectile. Failure modes of front composite armors are mainly fiber tensile rupture while for steel backing plates, failure modes are primarily petaloid damage. The whole energy-absorbing capability of combined targets increases with increasing the area density of front composite armors. It is shown that theoretical predictions coincide with the experimental results in terms of residual velocities. [ABSTRACT FROM AUTHOR]

Copyright of Journal of National University of Defense Technology / Guofang Keji Daxue Xuebao is the property of NUDT Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A contamination prevention method using jet flow was proposed to protect the optical window in laser ignition system from attachment of combustion remains of propellants and decrease of transparence. The pressure in chamber and gas flow between the chamber and the cavity were analyzed by using interior ballistics calculation. The mathematical model of the particle movement in the chamber was established and calculated. The calculation and simulation results indicate that the new proposed method is effective to protect the optical window, the jet flow interference can reduce the particles reaching to the optical window area effectively. The structural parameters are optimized for guns with different calibers based on the simulations. A screen tube is proved to be useful to enhance the protection effect. The increases of the length of cavity or the angle of diverting orifice can lead to a better protection. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To simplify the complexity of moving boundary treatment in the two-phase flow numerical simulation and improve the computational accuracy of moving boundary treatment, a two-dimensional twophase flow model based on ALE method is established. The governing equations are discretized with the TVD-type MUSCL scheme to obtain a second order accuracy in finite volume form. A two-step and fourthorder Runge-Kutta method is used to solve the source terms. The dynamic mesh update method and numerical method are verified by a standard test with the exact solution. The numerical application on a large caliber guided projectile shows the complete development and the two-phase flow characteristics of the interior ballistic process. The calculated results are in good agreement with the experimental results. The effects of different ignition conditions on interior ballistic performance are investigated. The study lays a theoretical foundation for deep optimization of the interior ballistic performance and firing safety. [ABSTRACT FROM AUTHOR]

From 16th to 19th century there is an intensified intercommunion for the technology of artillery-making and applying for guns between West and China through introducing science and technology by Jesuits. During this transmission, western knowledge of ballistic was introduced and combined with traditional Chinese knowledge and experiences, and this was reflected with concentration in the military books of Late Ming and Early Qing. This paper especially differentiates and analyses the description for trajectory knowledge in military books during this period from the aspect of terminology. Through analyzing the descriptions about devices for aiming, ballistic curve, and explanation for flight, the paper manifests that China of Late Ming and Early Qing inherited qualitative description for traditional cast weapon with gun-powder, as well as absorbed western technology and theory for trajectory, hoping that it might be of help to reflect the development and the evolution of Chinese ballistics after the introduction of western ballistics into China since 16th century. [ABSTRACT FROM AUTHOR]

A stochastic exterior ballistic model of parachute-stabilized and ribbon-stabilized submunutions is presented to overcome the disadvantage of low precision based on classical interior ballistics. Some random parameters were considered to improve calculation precision in the model. As it includes stochastic differential equations, the model becomes difficult to find out analytic answers. To overcome this, Monte Carlo method is made use of to seek its approximate key. In a submunitions dispersion test, this model and classical exterior ballistic model are used together to calculate submunitions' dispersed location. The results showed that this stochastic model has better precision than that of classical model. [ABSTRACT FROM AUTHOR]

The numerical simulation accuracy of interior ballistics of ultrahigh firing rate guns depends on the accuracy of calculating the drag force acting on projectile nose. In order to improve the numerical simulation accuracy of interior ballistics of ultrahigh firing rate gun, the secondary development tool UDF is used to couple FLUENT and the classic interior ballistic (CIB) model for the calculation of flow field in front of projectile. The nose drag force of the second launched projectile is obtained, and the variation law of nose drag force at different firing rates is analyzed. The simulated results show that the propellant gas flow field distribution can be obtained by the two-way coupling of FLUENT and CIB model, and the accuracy of calculating the nose drag force is improved. The nose drag force increases quickly after launching, and then decreases after it reaches a maximum value until the projectile leaves the muzzle. This variation law is common at different firing rates. When the firing rate reduces, the increased amplitude of nose drag force decreases at the earlier stage of projectile movement, and its decreased amplitude also decreases at the later stage of projectile movement. [ABSTRACT FROM AUTHOR]

Inertia-ratio is an important feature for mid-course ballistic target recognition. It's necessary to know the ballistic target's to calculate the Inertia-ratio precession parameters. But estimating the precession parameters of cone-cylinder ballistic target needs to know some of its structure parameters. Firstly, this paper analyzes the procession feature of the cone-cylinder ballistic target and its High Range Resolution Profiles (HRRPs). Then based on the analysis of the precession of cone-cylinder target, the 'Pseudo-inertia-ratio' feature is proposed, which can be estimated without knowing the structure parameters of the cone-cylinder target. And the method and steps to extract the 'Pseudo-inertia-ratio' feature based on HRRPs are presented. Finally the simulation results are given to validate that the 'pseudo-inertia-ratio' feature and the presented method are effective and applicable. [ABSTRACT FROM AUTHOR]

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Objective: To observe the characteristics of vertical cast-off bloodstain pattern by different hitting-tools., Methods: The regular hitting tools, a kitchen knife, a dirk, a plane set-hammer and an iron pipe, were selected. At a distance of 30 cm away from the wall, the hitting tool with 5 mL fresh chicken blood made the cast-off bloodstain from top to bottom. Then the holistic distribution characteristics (length, width and density) of cast-off bloodstain and morphology characteristics (length, width and contact angle) of first single cast-off bloodstain were analyzed., Results: The distribution length of cast-off bloodstain formed by dirk was minimum (P < 0.05). The distribution width of cast-off bloodstain formed by kitchen knife was minimum (P < 0.05). Except the pair of kitchen knife and plane set-hammer, the distribution density between each two tools had statistical differences (P < 0.05). The length of first single cast-off bloodstain formed by plane set-hammer was longest compared (P < 0.05). The width of first single cast-off bloodstain had statistical differences between kitchen knife and plane set-hammer, and between dirk and plane set-hammer (P < 0.05)., Conclusion: The type of hitting tool could be inferred by the specific characteristics of cast-off bloodstain pattern formed by every specific type of hitting tool in crime scene.

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using data fusion algorithm to complete the high-precision exterior ballistic measurement has strict technical requirements for the time synchronization of each measuring element. By analyzing the effect of time being not in synch on ballistic measurement precision of fusion, the factors resulting in time not synchronized of velocity measurement are discussed, and effective mathematic correction model is established. Aiming at phenomenon of the fusion ballistic velocity anomalies ultra difference, integral point shift and propagation delay correction model algorithm based on measurement equipment velocity data calculation model is proposed according to measurement error model formula and radio measurement results, and it is applied in synchronization correction of the sub projectile data fusion. The application results show that the integration of the trajectory deviation is better than 0. 04 m/s, the accuracy is improved by more than 4 times. Because the distance and angel of subgrade radio measurement system have similar features of time being not in synch, the model can also be used as a general method in the processing of measurement element fusion trajectory calculation. [ABSTRACT FROM AUTHOR]

Based on the coupled equation of classical interior ballistic theory and computational fluid dynamics theory, the gas flow in bore of piston high-low pressure launcher is modeled using Fluent and analyses the gas flow in the launch process to optimize the structure of piston high-low pressure launcher in this paper. Experiments are carried on to validate the analyses. The results of simulation and experiments show the details of interior flow field according to its 3-D model, which provides the theoretical basis for the design of piston high-low pressure launcher. [ABSTRACT FROM AUTHOR]

The effect of toughened compound alumina ceramic on anti-penetrating performance is investigated in this research. Simulations on tungsten long rod penetrating into AD95 ceramic/ metal targets and 10% zirconia toughened alumina (ZTA) ceramic/metal targets were done by using AUTODYN software and JH-2 model. Anti-penetration performances of AD95 and ZTA ceramic have been compared to that of 45 steel. The results show that, under the impact with high velocity, ceramic materials have higher protection capability than that of 45 steel. By comparison, both the thickness efficiency and mass efficiency of ZTA ceramic are higher than that of AD95 ceramic. The numerical results show that the improvement on ballistic resistance could be clearly observed by increasing the toughness of target with ZTA ceramic. [ABSTRACT FROM AUTHOR]

The major emphasis of this article is on three kinds of ballistic & stab resistant material, which are shear thickening fluid (STF) -aramid fiber composite, thermoplastic-aramid fiber composite and multi-direction UHMWPE LTD. Both the technical characters and researching status of these materials have been illustrated. The development trend of ballistic & stab resistant material has also been discussed. [ABSTRACT FROM AUTHOR]

The initiation behavior of covered explosives by reactive fragments was studied by ballistic experiments, and its initiating ability was compared with that to the explosive subjected to impact of the tungsten alloy fragment having the same mass as the reactive ones. The shock initiation behaviour of fragments to covered explosives has been simulated in the platform of AUTODYN-2D, and the initiation mechanism of reactive fragment was distinctly obtained by comparison of the numerical and experimental results. The research shows that the reactive fragment with a mass of 10 g and a velocity above 1 287 m/s is able to initiate the Composition-B covered by a 10 mm thick aluminum plate or a 6mm thick A3 steel plate. However, the tungsten alloy fragment only results in mechanical damage on the covered explosive and fails to initiate the Composition-B at an impact velocity of 1 527 m/s. The dominant initiation mechanism of reactive fragment to covered explosive is the violent chemical reaction of reactive materials inside the explosive, which decreases significantly the demand of kinetic energy for the fragment. [ABSTRACT FROM AUTHOR]

This paper put forward a method of reducing the armor-piercing projectile hit probability by investigating the characteristics of modern tank fire control system and armor-piercing projectile. A hit probability model based on traditional firing theory was established and analyzed. The results show that this method is effective. The further study points out that the most effective way to decrease the hit probability is reducing the response time of the target. [ABSTRACT FROM AUTHOR]

Presents an assessment of the lethality capabilities of impact initiated reactive fragments and a dynamical testing technique for the energy release characteristics of reactive fragments. The energy release characteristics of three reactive fragments with various formulations were measured by ballistic experiments. The results showed that all three reactive fragments could undergo a rapid volatile chemical reaction and release great amounts of thermochemical energy under strong impact loadings, And the energy release efficiency of reactive fragments is markedly influenced by the impact velocity. The released chemical energy of reactive fragment reached about 5 times its kinetic energy at an impact velocity of 1 500 m/s, enhancing greatly its lethal capabilities. [ABSTRACT FROM AUTHOR]

Characteristics of target groups are studied when damaging upon important target groups in war. In the basis of simplifying the critical components and analyzing the interactive states of shock wave field and critical components, a model for the kill probability of multiple target damaged by shock wave is established according to the characteristics of target groups. Under the condition of fixed ballistic parameters, warhead structure and charge, the law of kill probability of target groups is obtained, which changes with the circle error probability(CEP), height of burst and different aiming point. The effect of these factors on kill probability is analyzed. The results showed that the damage effects from the pressure of shock wave on the target groups are obvious. The results of calculation and analysis can provide useful reference basis for optimized design and efficiency evaluation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A new prediction method based on radial basis function (RBF) neural network and an unscented Kalman filter technology is proposed for the precise and quick prediction of impact-point without exact flight data. Firstly, RBF neural network approximated external ballistics equation is used to predict the projectile impact-point, and the improved quantum-behaved particle swarm optimization algorithm is used to optimize the training method. On this basis, the tentative prediction data is processed with unscented Kalman filter. At last, the prediction simulation is carried out. The results show that a high prediction precision can be reached under the condition of input data with noise. The method proposed in this paper is efficient and available for impact-point prediction. [ABSTRACT FROM AUTHOR]

For the technical scheme of the two-dimensional trajectory correction projectiles (TDTCPs) with drag brake and despining blade, the mathematical model of two dimensional trajectory corrections is discussed based on the theory of exterior ballistics. An approximate formula for predicting the ballistic drift and trajectory correction quantity is deduced with respect to the process of lateral trajectory correction. The capability of lateral trajectory correction and the flight stability of TDTCP are also analyzed. By comparing with the results of flight test, the accuracy and effectiveness of this approximate calculation method are verified. The result of the approximate method is in accordance with those of 6DOF trajectory model and firing test, and the maximum error is no more than 40 m. All the work is valuable for further research. [ABSTRACT FROM AUTHOR]

A three-dimensional two-phase flow model based on arbitrary Lagrange-Euler method is established to improve the computational accuracy and cost of three-dimensional simulation for interior ballistic in guns. The three-dimensional governing equations are discretized with the MUSCL scheme. The fourth-order Runge-Kutta method is used to solve the time orientation. The numerical method is coded and compiled in the MPI parallel environment. The numerical simulation shows the detailed three-dimensional development of the two-phase flow behavior. The calculated results are in good agreement with the results in Ref.［20］. The effects of different igniter lengths and diameters on interior ballistic performance are analyzed. Parallel numerical studies show that the parallel efficiency can be reduced by about 50% using interior ballistic three-dimensional calculation of 24 processes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Modern Medicine & Health is the property of Journal of Modern Medicine & Health and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concept of dual-spinning becomes a new approach to upgrade a conventional spin-stabilized projectile, wherein an actuator is used to control the phase of forward canards. To design and analyze the inner control channel efficiently, a dual-spin ordinary differential equation, including a quasi-steady aerodynamic model and an optimized LuGre friction model, is established. All aerodynamic and kinematic data in time-domain, as input in least square estimation, is obtained in transient numerical model and dynamic wind tunnel test. The results indicate that the side force and roll moment supplied by canards are affected by phase angle and roll rate, and the estimated accuracy of quasi-steady aerodynamics is lower than 4×10-3. The friction between forward and aft parts is a function of axial pressure and relative roll rate, which can be estimated by the optimized LuGre model. The feasibility of using the dual-spin model to predict the canard movement is validated by measurement in a flight test. The proposed approach promotes the pace of engineering application of dual-spin projectiles. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the two-dimensional rheological behavior of a long-rod projectile penetrating into steel target, a two-dimensional elbow-streamline penetration model was developed based on long-rod projectile hydrodynamic penetration model, mass conservation during penetration and elbow model. The impact velocity, reference point angle and reference point radius are considered in the proposed model. The material flow around the nose of tungsten long-rod projectile penetrating into a steel target was analyzed based on the proposed model and compared with the test results. The results show that the material flow around the tungsten long-rod projectile nose is non-uniformly distributed, and the flow velocity on the outer side is less than that on the inner side. The pressure on the long-rod projectile nose material is distributed gradiently. The proposed model is used to describe the material flow of long-rod projectile nose during penetration, and explain the process of transition from fluid to solid in the projectile nose at the final stage of penetration. It reveals the relation between the change of ballistics channel and the penetration state transition of projectile. [ABSTRACT FROM AUTHOR]

The influence of bore damage on interior ballistic performance and muzzle-leaving state of bullet is studied, and the mechanism of how bore damage leads to the end of barrel's life is explored. The accurate thermo-mechanical coupling finite element analysis (FEA) models of barrels with bore damage at different life periods are established based on the distribution and evolution rule of bore damage obtained through systematic life tests. The changing rules of interior ballistics performances and muzzle-leaving states of 12.7 mm bullet with the evelopment in bore damage are obtained through numerical simulation which combines the interior ballistics process and the explicit finite element method through Fortran subroutines. The coupling model of bullet and gun barrel is proved to be effective by comparing the calculated results of interior ballistic parameters with experimental results. The simulated results show that the initial disturbances of bullet at muzzle, the reduction in rotational velocity and the variation in bullet's surface topography increase as the firing cycle increases, especially in barrel's later lifetime. Variation in muzzle-leaving state of bullet is the key factor for barrel's life end. Research results have important significance on further studying how bore damage degrades bullet's exterior ballistics performance and the end-of-life mechanism of barrel. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reverse ballistic impact test has been widely used to research the materials and structural dynamic response, in which the measuring devices can be installed on the free-free beam to obtain the more accurate measured results. The 20° reverse ballistic oblique impact tests of free-free beam are carried out, and the digital image correlation (DIC) technique is used to measure the real-time dynamic response. The failure criterion is introduced and the simulated results are considered to solve the dynamic responses of free-free beam under axial and transverse impact loading. The results show that the calculated bending shape agrees well with the experimental result, and is better than that in Ref［4］. The reverse ballistics is equivalent to the forward ballistics for the reverse ballistic mass ratio mγ⩾10. The proposed method can also be used for solving the dynamic response of projectile during penetration. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The canard and bearing are dynamically modeled to improve the dual-spin trajectory model based on Euler approach. The working condition of electromagnetic actuator of trajectory correction projectile with decoupled canards (TCPDC) is investigated. The designed working condition is validated by the parameters derived from the dual-spin trajectory. The spin-rate and electromagnetic torque of actuator are extracted based on the rolling states of projectile and canards. The calculated results indicate that the canards spin in relative to the opposite direction of projectile body rapidly after launch, and then spin down at a relatively low and stable rate, which is hardly affected by the launching conditions. The spin rate of projectile is the main factor, which leads to a large range of actuator' s working speed. After the projectile flies through an apogee, the spin rate of actuator could be stably maintained between 130 and 230 r/s, and the essential torque is less than 0. 5 N·m. In terms of the working range of actuator, the optimal starting control point should be in the segment behind the apogee. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ballistics / Dandao Xuebao is the property of Journal of Ballistics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)