摘要
鱼雷涡轮机叶轮体积小、质量轻、叶片短,常用的接触式加速度传感器的附件质量对叶轮模态的测试精度有直接影响,且无法在短叶片上布置。为了完全消除传感器的附加质量影响,增加测点数量,提高测试精度,将非接触式激光测振技术和聚偏氟乙烯(PVDF)压电薄膜引入叶轮模态测试中,解决鱼雷涡轮机叶轮的模态测试难题,测量出叶轮前5阶固有频率和振型。将2种测振方法对比分析,结果表明,2种测振方法测量叶轮固有频率精度均较高,激光测振技术测量叶轮模态可布置多个测点、测量范围宽、振型结果显示清晰直观;PVDF压电薄膜在较高频率范围的测试精度和抗干扰性较好,但不适用于低频测量,且测量的叶轮模态振型难以辨识。
Torpedo turbine impeller has small size, l ight weight and short blades, so the additional mass of a common contact acceleration sensor directly affects the measurement accuracy of impeller modal, and the sensor cannot be installed on the short blade. To completely eliminate the influence of the sensor＇s additional mass and increase the measurement points and accuracy, the non-contact laser measurement technology of vibration and the PVDF piezoelectric film are introduced into the impeller modal test for improving the measurement accuracy and obtaining the first five orders of impeUer natural frequency and vibration modes. Comparison between the contact and non-contact vibration measurement methods shows that： both methods achieve high measurement accuracy of impeller natural frequency, while the non-contact laser measurement technology of vibration allows more measurement points for impeller vibration modal and wider measurement range, and achieves clearer modal shape; PVDF piezoelectric film has higher measurement accuracy and anti-interference ability in higher frequency range, but it is not suitable in lower frequency range and the obtained modal shapes of the impeller are difficult to be identified.
出处
《水下无人系统学报》
2017年第2期94-100,共7页
Journal of Unmanned Undersea Systems
基金
船舶工业国防科技预研基金项目(14J4.4.1)
关键词
鱼雷涡轮机
叶轮
叶片
激光测振
PVDF压电薄膜
模态测试
torpedo turbine
impeller
blade
laser measurement of vibration
PVDF piezoelectric film
modal test
