共查询到19条相似文献,搜索用时 250 毫秒
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为研制水下爆炸冲击平台,初步设计平台隔振系统和两种船体结构,运用有限元分析软件ABAQUS,对安装隔振系统前后平台在爆炸载荷作用下的冲击响应进行计算分析,预估平台抗冲隔振效果。采用声固耦合方法,考虑空化效应和材料应变率的影响。仿真结果表明,在水下爆炸载荷作用下,采用加强的船体结构,平台船体底部的塑性变形显著减小,平台的垂向加速度峰值衰减率超过95%。经海上爆炸试验验证,数值仿真结果与试验值吻合良好,仿真设计方法合理。 相似文献
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为解决潜艇水下毁伤单次试验中测试测量要素与数据分析不够完备的问题,着眼单次试验获取尽可能多的有效试验数据,提出一种潜艇水下爆炸毁伤试验的综合测试测量方法,分试验前、试验中和试验后3个阶段对测量要素进行了较为全面的分析,并提出了相应的测点布设方案和试验数据处理方法,通过仿真试验对综合测量与分析方法进行探讨,指出了测试测量与数据分析时需要注意的问题,可为潜艇水下毁伤试验的开展提供参考. 相似文献
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防护板在舰船上的应用非常广泛,它对于提高舰船抵抗水下爆炸冲击波载荷性能、抗碰撞冲击性能等都具有重要作用.文中利用薄壁圆管的吸能特性设计了离散型和紧密型圆管夹心板,使用大型非线性有限元软件MSC.Dytran建立水域、炸药及防护板的三维有限元模型,并进行水下爆炸数值仿真计算,从板的吸能能力、加速度响应、变形量三个方面分析了两种夹心板和普通平板在水下爆炸载荷作用下的抗冲击性能,仿真计算结果表明离散型夹心板的抗爆性能优于紧密型夹心板和普通平板. 相似文献
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穿舱爆炸舰船局部毁伤效果模型实验方案研究 总被引:1,自引:0,他引:1
考虑了爆轰波和结构塑性变形的相似律问题,研究在大尺度缩比船体模型在穿舱爆炸条件实验中,使用畸变相似律处理模型得到对原模型局部毁伤效果等效评估的方法。通过对4种船体结构缩比实验方案进行穿舱爆炸数值模拟分析,并对实际模型毁伤效果评估误差进行总结,得到当缩尺比为λ=0.25、畸变比为φ=2.5时,实验模型能在工程允许的误差范围内可实现对原模型局部毁伤效果的准确评估,得到满足生产可控性和经济性的最终实验方案。结论可为大尺度缩比船体模型穿舱爆炸实验的应用提供参考。 相似文献
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轻型鱼雷受水下爆炸作用的冲击响应对鱼雷设计具有重要意义;利用ABAQUS软件验证了材料动态失效对圆桶结构水下爆炸数值仿真的影响,并对美制MK44型鱼雷受深水炸弹攻击下的冲击响应进行仿真计算,给出了两种失效准则下的安全距离和破坏模式;结果表明,考虑材料动态失效时应使用水为主耦合面的公式进行计算,结构变形响应取决于加筋方式;研究可为可对轻型鱼雷的设计和考核提供参考。 相似文献
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鱼雷武器近场爆炸毁伤试验风险高、试验环节多、实施复杂,为解决近场爆炸作用下舰船的毁伤测量问题,分析了测量的关键环节,提出采用气液缓冲器作为缓冲原件对测量设备进行缓冲防护,采用远程无线遥控爆炸解脱加水激活电池接触海水解脱两种方式互相备份的解脱方式确保测量爆炸后测量设备与靶船的可靠分离,采用无线传输方式进行测量数据转存备份,从端采用全向天线,主端采用三个定向天线组合的方式,通过实际测试验证了方法的可行性。研究内容为近场爆炸毁伤测量的实施提供了一种思路,也可以为相关工作开展提供参考。 相似文献
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Jinpeng Wang Shan Chang Geng Liu Lan Liu Liyan Wu 《Structural and Multidisciplinary Optimization》2017,56(5):1093-1108
In this paper, an optimum rib layout design method for reducing radiated noise is proposed based on topology optimization and acoustic contribution analysis. According to radiated noise depends on acoustic transfer vector (ATV) and normal velocity, the influence of rib layout on ATV is analyzed and it is found rib layout has little influence on ATV. Only if a region has maximum acoustic contribution, the normal velocities on this region can have the most remarkable influence on radiated noise. So the determination procedure of region with maximum acoustic contribution is introduced. Based on this, the topology optimization model is established to minimize the normal velocities on this region. Ribs can be arranged according to the optimum topologies to reduce the normal velocities, which in turn results in a reduction of radiated noise. The topology optimization model is used to obtain the optimal rib layout by taking a plate-like structure as an example. The plate is fixed along all side edges and excited by a time-harmonic external point load with different prescribed frequencies. The radiated noise is simulated using the finite element method and boundary element method. Four plates are manufactured according to the optimal rib layouts for different single frequency excitation. Modal test and sound measurement are conducted to validate the proposed method. The influence of loading position on the topology optimization results is also investigated and discussed. 相似文献
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针对炸高测量系统结构复杂、布阵繁琐、低信噪比下的炸高测量精度偏低的问题,提出一种立体六元声光阵列的炸高测量方法;详细介绍了该方法的炸高测试原理及结构组成,应用Matlab建立了声光阵列结构的数学模型,深入分析了该结构的测量原理和最佳测量高度;仿真验证结果表明:该方法适用于爆炸高度为20~60 m范围内的炸高测量,测试时应保证爆炸声信号到达传感器的时延估计误差小于20μs、声光信号到达基阵时延估计误差绝对值在4 ms范围内;最终靶场实验结果表明:在低信噪比的情况下,采用立体六元声光阵列结合改进的广义二次互相关算法在最佳测量高度范围内的炸高测量精度达到5%,可以应用于靶场炸高测量. 相似文献
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Ma Ge 《Computers & Structures》2005,83(27):2185-2196
A damage detection method is presented for the identification and quantification of damage that leads to a change in the structure’s mass and/or stiffness properties. The proposed method requires the use of finite element to model the structure in its undamaged state as well as information on the dynamic properties such as frequencies and mode shapes of the structure in its damaged state. The technique is applicable to any structure that can be accurately modeled using the finite element method and whose frequencies and mode shapes can be reliably measured. A structure pseudo force vector derived from the residual force method is described to locate the damaged regions in the structure. A matrix condensation approach in conjunction with a proportional damage model is then employed to quantify the damage by calculating the change in stiffness and mass properties of the damaged elements in the structure. The validity of the method is demonstrated by applying it to three structures: a beam, a frame and a plate. It is shown that if the amount of damage is not excessively large, the proposed method can be used to detect damage in these structures even when the measured system dynamic properties are slightly erroneous. 相似文献
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轮胎机械特性虚拟试验场 总被引:2,自引:0,他引:2
轮胎对汽车性能具有十分重要的影响,因此对其进行机械特性试验是十分必要的.而传统的在室外进行的轮胎试验总有不少干扰,在室内进行试验又会受到实验室条件的限制.为了克服传统试验的不足,将虚拟试验场技术与有限元和动力学方法相结合,以P215/70R15轮胎有限元模型为对象,设计了轮胎径向刚度、外倾刚度和侧偏刚度虚拟试验场,分析了轮胎径向刚度、外倾刚度、侧偏刚度与胎压、径向载荷、车速等因素的关系,与实际比较符合,证明了轮胎机械特性虚拟试验场建立的可行性,为轮胎机械特性试验提供了一种新的有效的方法. 相似文献