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为了提高制简易制导火箭弹命中目标的精度,针对简易制导火箭弹用电视位标器的可靠性与冗余设计问题,提出了一种无位置传感器无刷直流电机的控制方案。新方案采用了无位置传感器控制原理及方案运行模式下的转子位置检测技术,利用电机反电动势过零点并经过低通滤波获取电机转子位置信息的方法。在Matlab/Simulink环境下,先建立独立的功能模块,再进行功能模块的有机整合,搭建了系统的仿真模型。且试验结果与仿真结果对比表明,无位置传感器电视位标器电机系统模型具有转速响应好和仿真速度快的优点。证明改进方案克服了电视位标器系统有位置传感器工作模式响应特性的不足,节约了冗余设计的空间与成本。 相似文献
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Interface debonding between particle and matrix in composite propellant influences its macroscopic mechanical properties greatly. For this, the laws of interface cohesive damage and failure were analyzed. Then, its microscopic computational model was established. The interface mechanical response was modeled by the bilinear cohesive zone model. The effects of interface properties and particle sizes on the macroscopic mechanical behavior were investigated. Numerical simulation of debonding damage evolution of composite propellant under finite deformation was carried out. The debonding damage nucleation, propagation mechanism and non-uniform distribution of microscopic stress-strain fields were discussed. The results show that the finite element simulation method based on microstructure model can effectively predict the trend of macroscopic mechanical behavior and particle/matrix debonding evolution process. It can be used for damage simulation and failure assessment of composite propellants. 相似文献
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双圆弧超音速喷管的推力偏心特性 总被引:1,自引:0,他引:1
用三维非对称流场数值模拟的方法研究了双圆弧超音速喷管的推力偏心特性,给出了在改变喷管长度和喷管扩张比两种情况下,喷管侧向推力分量沿轴向的变化及其零点位置在轴线上的分布。结果表明,侧向力第一零点随喷管长度和扩张比呈现微弱的、非线性变化,而第二零点的位置与喷管长度和扩张比有很好的线性对应关系。 相似文献