串联发射弹丸内弹道力学特性测试方法研究

针对小口径高射频串联发射弹丸的内弹道力学特性测试问题,提出了基于弹载存储测试技术的弹底压力、弹前压力同步测试方法。设计了模拟弹和小型聚偏二氟乙烯(polyvinylidene difluoride, PVDF)压电式力传感器,将力传感器作为底螺与头螺部件承受并测量弹底压力与弹前压力,在发射过载条件下进行了传感器力学分析并推导了受力与输出的关系方程;分析了传力块的质量、厚度,PVDF薄膜的厚度、面积对传感器动态特性和温升的影响;进行了力传感器灵敏度理论建模与分析并开展了标定试验。结果表明,PVDF薄膜预紧力越大,传感器灵敏度越小。开展了串联发射试验,测试结果和内弹道数值模拟计算结果吻合较好。

Test method for interior ballistic mechanical characteristics of series launched projectile

Here,aiming at the test problem of internal ballistic mechanical characteristics of small caliber high radio frequency series launched projectile,a synchronous test method of bottom pressure and front pressure based on missile borne storage test technology was proposed.Simulated projectiles and small polyvinylidene difluoride(PVDF)piezoelectric force sensors were designed.Two force sensors were used as bottom screw and head screw components to bear and measure the projectile’s bottom pressure and front pressure.The sensor mechanical analysis was performed under the condition of launch overload,and the relation equation between force and output was deduced.Effects of mass and thickness of force transfer block,thickness and area of PVDF on dynamic characteristics and temperature rise of the sensor were analyzed.Theoretical modeling and analysis for the sensitivity of force sensor were performed,and calibration experiments were done.The results showed that the larger the preload of PVDF,the smaller the sensor sensitivity;series launch tests are conducted,and the test results agree better with interior ballistic numerical simulation ones.