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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]

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]

In order to evaluate ballistic consistency under small sample circumstance, an evaluation method of ballistic consistency is proposed based on the normal distribution small sample compatibility theory. This method is to compare the calculated order statistics and the simulated critical value to determine the ballistic consistency. The main advantage is not necessary to calculate the position- scale estimate value, so it could decrease the calculation error due to small sample size. The calculation shows that this method is better than matched pair t test and probability circle sequential test under small sample circumstance (n≤5 ). [ABSTRACT FROM AUTHOR]

The evaluation of penetration effectiveness of ballistic missiles under the cover of decoys is an important issue. The missile penetration probability is used as an evaluation index of penetration effectiveness. Based on the different decoy jamming and anti-missile interception strategy, the penetration effectiveness models of single and multiple ballistic missiles are built. Considering the effect of decoys, the penetration effectiveness of multiple ballistic missiles is quantitatively studied. At last, the results of a sample are analyzed, and the models are verified, from which some valuable conclusions are got. The research result has a certain reference value to the simulation and evaluation of penetration ability of ballistic missile. [ABSTRACT FROM AUTHOR]

In order to distinguish 1 cm² copper crusher gauge, a special experimental device which can supply required pressure source by volume expansion is proposed and designed. An interior ballistic model of the device is set up and simulated based on the interior ballistic analysis and the flow equation of the working chambers. The pressure and flow characteristics of propellant gas between bore and chamber are obtained. And the influences of initial volume and position of the high pressure chamber on its maximum pressure are studied. The maximum pressure of the high pressure chamber can be adjusted to about 39.0 MPa under the condition of the known parameters. Compared with the experimental results, the maximum deviation is 4.9%. The device can meet the requirement of identifying copper crusher gauge. [ABSTRACT FROM AUTHOR]

In order to analyze the lethality of a forward enhanced lethal HE (high explosive) projectile against personnel targets, the static explosion experiments are made on the forward enhanced lethal HE projectile and the conventional HE projectile, which have same structural characteristic parameters. A calculating model of the lethality against personnel targets is established. The lethal powers of two kinds of projectile against personnel targets in same terminal conditions are comparatively calculated. The result shows that the forward enhanced lethal HE projectile can produce a fragment damage area compared with the conventional HE projectile so that it makes the killing area for personnel targets being increased by 147.3%. Its lethality against personnel targets is enhanced effectively. [ABSTRACT FROM AUTHOR]

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]