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1.
两种TA TB的热膨胀研究   总被引:2,自引:0,他引:2  
为了优化三氨基三硝基苯(TATB)为基的混合炸药配方,研究了碳酸铵法所得细颗粒TATB(F-TATB)和氨气法所得粗颗粒TATB(L-TATB)在热循环作用下产生的膨胀。对比测试了F-TATB和L-TATB的物化性能,采用室温→-40℃→75℃→室温的高、低温度热循环试验方法,获得了两种TATB压制药柱(30 mm ×5 mm)经过热循环试验后的膨胀参数,结果表明:热循环作用下两种TATB均产生了不可逆尺寸长大且随着循环次数增加药柱尺寸趋向恒定,首次热循环试验后L-TATB的膨胀率大于F-TATB;试验还发现L-TATB的总膨胀率小于F-TATB,这表明L-TATB较F-TATB更快趋于尺寸稳定。  相似文献   

2.
梯黑药柱的改性研究   总被引:7,自引:5,他引:2       下载免费PDF全文
用65份黑索今(0.65份高聚物包覆的)和35份梯恩梯进行真空熔药(温度85~90℃),然后注入模具中,在室温下降温,凝固制成梯黑药柱。用渗油性和尺寸测量的方法测得结果表明:该药柱的渗油性和不可逆长大量,均明显地低于含MNT的梯黑(RHT-902)药柱。  相似文献   

3.
高聚物改性B炸药研究(Ⅱ)   总被引:3,自引:3,他引:0       下载免费PDF全文
防治B炸药渗油、抑制其药柱尺寸不可逆长大、增强其力学性能和降低感度是B炸药改性研究的重要内容。本课题采用一种芳香共聚物包覆RDX制作了一种改性B炸药。检测结果表明,B炸药经过改性后,渗油率降低了47.6%,强度提高了2倍,尺寸长大率降低了75%,感度也有所降低。  相似文献   

4.
在弹药制造过程中,药柱外型尺寸将直接影响弹药的性能。针对人工检测效率低且重复性不好以及传统机器视觉普适性差的特点,提出了基于傅里叶变换轮廓术的检测方法。该方法采用面阵CCD相机采集受药柱表面调制的光栅云纹图像,再对图像进行矫正、相位提取及重建,最后通过尺寸标定得到药柱三维尺寸。实验结果表明,该方法能同时检测多个药柱的尺寸,极大地提高了检测效率,能检测出药柱的微小变形,检测误差在0.2%以内。  相似文献   

5.
为了研究套管装药发动机典型载荷和温度冲击载荷下的药柱结构完整性,使用Abaqus软件对某套管发动机药柱进行了有限元分析,分别计算了固化降温、点火内压、2次与8次温度循环下的药柱温度场和应力场,得到了不同载荷下药柱危险部位的应力应变,对比了不同温度循环次数下内外环药柱温度变化曲线和特定点温度历程。有限元计算结果表明,不同载荷下套管装药外环药柱中孔、前、后人脱凸环位置为应力集中区,而本文载荷下前人脱凸环为最危险部位;内环药柱比外环药柱温度变化幅值小,并且变化滞后于外环药柱;增加温度循环次数,最终状态下药柱应力场变化不大。  相似文献   

6.
PBX药柱温升过程中的性能变化研究   总被引:1,自引:1,他引:0  
兰琼  鲁建英  张明  雍炼 《含能材料》2008,16(6):693-697
为全面了解温升过程中PBX药柱温度、应力和尺寸变化情况,利用瞬态-应力耦合有限元法对药柱温升过程进行模拟。结果显示:药柱温升过程中,热量逐渐向内部传递,初始升温阶段应力增大很快,最大达到2.37MPa,随着内外温差的减小而逐渐减小;药柱尺寸增大,密度减小约0.008g.cm-3。通过模拟可以初步确定药柱温升过程内部应力变化规律,预估尺寸和密度变化量,优化设计了一种炸药加热工艺,即将加热分四段进行,尽量降低升温速率,保证至少1800s的恒温时间。  相似文献   

7.
双向压药工艺在传爆药柱生产中的应用   总被引:11,自引:0,他引:11  
吴学易 《火工品》1996,(4):7-12
介绍了双向压药工艺的理论根据、原理及发展情况。这种工艺可以提高大尺寸传爆药柱的内在质量,药柱成型性好,而且密度分布均匀。  相似文献   

8.
含铝炸药作功能力和JWL状态方程尺寸效应研究   总被引:4,自引:0,他引:4  
为了研究含铝炸药作功能力和Jones-Wilkins-Lee(JWL)状态方程尺寸效应,进行了含铝炸药25 mm和50 mm两种药柱尺寸的圆筒试验。先采用解析求解,然后进行二维数值模拟修正,得到了含铝炸药药柱两种尺寸的JWL状态方程参数。结果表明:大尺寸的含铝炸药药柱作功能力比小尺寸强;大尺寸的含铝炸药药柱状态方程参数相比小尺寸同种炸药,A稍增大,B增大较多,C基本不变,R1稍小,R2增大较多,ω稍小。  相似文献   

9.
水下航行器热动カ系统固体药柱燃烧模型与仿真   总被引:1,自引:0,他引:1  
张进军  钱志博  杨杰  闫萍 《兵工学报》2006,27(5):817-822
药柱的几何形状、尺寸和燃烧面积直接决定着水下航行器动力系统的启动特性,也影响着推进剂供应管路的设计,所以对药柱的燃烧特性进行精确建模。在建立药环和2种药柱的燃烧模型的基础上,同时引用其它部件数学模型,建立动力系统启动过程的完整数学模型,并采用Mat-lab进行仿真实验计算,研究2种药柱对启动过程的影响。结果表明,改进后的实心药柱能够很好地改善水下航行器热动力系统启动过程。  相似文献   

10.
《火工品》2018,(5)
为了探究HMX基混合炸药药柱的膨胀规律,对两种代表性的炸药药柱进行了压制压力、热循环和老化等试验,并对其影响机理进行了分析。结果表明:增加压制的压力,药柱密度会不可逆地增加,放置24h后药柱体积膨胀会逐渐减小;药柱增大主要出现在最初的几个热循环中,且随着循环次数的增加基本停止;在老化试验中药柱体积增加幅度最大也出现在最初的时间内,随着时间的增加,增加幅度逐渐减小,而药柱质量随老化时间的延长逐渐减小。  相似文献   

11.
The stability under illumination of transmission-mode GaAs photocathode sealed in the third generation intensifier is investigated by use of spectral response testing instruments. The variations of spectral response with the illumination times under weak and intense illumination are compared. The variations of photoemission performance parameters are also characterized. The results show that during initial several weak illuminations photocathode behaves no evident decay and a maximum sensitivity is achieved, while under intense illumination the sensitivity of photocathode begin to decrease largely at the first illumination. The calculated performance parameters show that the variation of surface escape probability with illumination times is a direct cause of instability of photocathode. It is also found that under intense illumination peak wavelength is moved towards short-wave and peak response is decreased, which shows that the ability of long-wave response of photocathode is decreased.  相似文献   

12.
A Passive Acoustic Radar is presented as a necessary complement to electromagnetic wave radar, which will be expected to be an effective means for detecting cruise missiles. Acoustic characteristics of supersonic flying projectiles with diverse shapes are expounded via experiment. It is pointed out that simulation experiment could be implemented using bullet or shell instead of cruise missile. Based on theoretical analysis and experiment, the ““acoustic fingerprint““ character of cruise missile is illustrated to identify it in a strong noise environment. After establishing a locating mathematical model, the technique of acoustic embattling is utilized to resolve a problem of confirming the time of early-warning, considering the fact that velocity of sound is much slower than that of light. Thereby, a whole system of passive acoustic radar for detecting supersonic cruise missile is formed.  相似文献   

13.
The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures,the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done,feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points.  相似文献   

14.
A novel image restoration scheme, which is super-resolution image restoration algorithm Poisson-maximum-afterword-probability based on Markvo constraint (MPMAP) combined with evaluating image detail parameter D, has been proposed. The advantage of super-resolution algorithm MPMAP incorporated with parameter D lies in the fact that superresolution algorithm MPMAP model is discrete, which is in accordance with remote-sensing imaging model, and the algorithm MPMAP is proved applicable to linear and non-linear imaging models with a unique solution when noise is not severe. According to simulation experiments for practical images, super-resolution algorithm MPMAP can retain image details better than most of traditional restoration methods; at the same time, the proposed parameter D can help to identify real point spread function (PSF) value of degradation process. Processing result of practical remote-sensing images by MPMAP combined with parameter D are given, it illustrates that MPMAP restoration scheme combined PSF estimation has a better restoration result than that of Photoshop processing, based on the same original images. It is proved that the proposed scheme is helpful to offset the lack of resolution of the original remote-sensing images and has its extensive application foreground.  相似文献   

15.
A nonlinear terrain following(TF) and terrain avoidance(TA) controller is proposed for missile control systems. Based on classical TF algorithm (adaptive angle method), a new method for TF controller is proposed by using angle of attack. A method of obtaining terrain outline data from digital elevation map (DEM) for TF control is discussed in order to save store space. A TA algorithm is proposed by using bank-to-turn technique. The block control model, which is suitable for backstepping design, is given for nonlinear model of missile. Making full use of the characteristics of the system and combining block control principle and backstepping technique, a robust controller design method is proposed. Uncertainties in every sub-block are allowed, and can be canceled by using the idea of nonlinear damping. It is proved that the state tracking errors are converged to a neighborhood of the origin exponentially. Finally, nonlinear six-degree-of-freedom simulation results for the missile model are presented to demonstrate the effectiveness of the proposed control law.  相似文献   

16.
The design problem of non-fragile estimator is addressed for a class of perturbed linear continuous systems. The perturbations occur on the plant and estimator parameters. The estimator designed should force the error system to achieve the desired decay rate and force the steady error variance less than the specified upper bound irrdevancy of the admissible plant perturbations and estimator perturbations. Consistency problem of the decay rate with the variance upper bound is first considered via linear matrix inequality (LMI) approach. The solution of the estimator parameter under specifications to be consistent is then discussed. The consistency condition of specifications and estimator parameter solution are transformed to feasible or minimum problems subject to a set of LMI respectively. The method is illustrated by a numerical example.  相似文献   

17.
The improved scene-based adaptive nonuniformity correction (NUC) algorithms using a neural network (NNT) approach for infrared image sequences are presented and analyzed. The retlna-like neural networks using steepest descent model was the first proposed infrared focal plane arrays (IRFPA) nonuniformity compensation method, which can perform parameter estimation of the sensors over time on a frame by frame basis. To increase the strength and the robustness of the NNT algorithm and to avoid the presence of ghosting artifacts, some optimization techniques, including momentum term, regularization factor and adaptive learning rate, were executed in the parameter learning process. In this paper, the local median filtering result of Xij ( n ) is proposed as an alternative value of desired network output of neuron Xij ( n ), denoted as Tij ( n ), which is the local spatial average of Xij ( n ) in traditional NNT methods. Noticeably, the NUC algorithm is inter-frame adaptive in nature and does not rely on any statistical assumptions on the scene data in the image sequence. Applications of this algorithm to the simulated video sequences and real infrared data taken with PV320 show that the correction results of image sequence are better than that of using original NNT approach, especially for the short-time image sequences (several hundred frames) subjected to the dense impulse noises with a number of dead or saturated pixels.  相似文献   

18.
The disadvantages of IR images mostly include high noise, blurry edge and so on. The characteristics make the existent smoothing methods ineffective in preserving edge, To solve this problem, a piecewise moment filter (PMF) is put forward. By using moment and piecewise linear theory, the filter can preserve edge. Based on the statistical model of random noise, a related-coefficient method is presented to estimate the variance of noise. The edge region and model are then detected by the estimated variance. The expectation of first-order derivatives is used in getting the reliable offset of edge. At last, a fast moment filter of double-stair edge model is used to gain the piecewise smoothing results and reduce the calculation. The experimental result shows that the new method has a better capability than other methods in suppressing noise and preserving edge.  相似文献   

19.
A best linear unbiased estimation (BLUE) algorithm for bistatic sonar localization is proposed. The Cramer-Rao bound for bistatic Sonar and the geometrical dilution of precision (GDOP) in different conditions are given. The simulation results show that the location accuracy of BLUE algorithm is higher than the weighted least square method.  相似文献   

20.
A fault diagnosis method of working position gear in a tank gearbox is put forward based on simulating the fault of working position gear in an actual tank, extracting the envelope of vibration signal by Hilbert transformation amplitude demodulation method, and zooming the low-frequency band to envelope signal.  相似文献   

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