一种高精度密度传感器的研究

圆短筒谐振式密度传感器的主要优点是适合于在线连续测量,测量精度高,易实现数字化传输,抗干扰能力强,稳定性和可靠性好.圆短筒谐振式密度传感器以圆筒谐振子为核心,基于正反馈原理,由激振元件、拾振元件、谐振子和放大电路组成高品质的闭环谐振系统.我们采用有限元法分析方法,研究计算了圆筒谐振子静力学特性和模态响应等动力学特性.设计了圆筒谐振子闭环振荡电路,单片机信号处理系统.对密度传感器进行标定和温度补偿.分析了影响测量结果的各个因素,给出了20℃时传感器测量结果的不确定度.通过实验可靠性高又实用的圆筒谐振燃油密度传感器测量精度达到0.4 kg/m.

Research on the cylinder short shell resonator densitometer

The Cylinder short shell resonating densitometer is advantageous in many aspects, for example, no infection on the fuel makes it suitable for continous in-line use, and digital output and transmission make it high immune to disturbance, very stable, reliable and precise. Based on the principle of positive feedback, the cylinder shell resonating densito-meter is a closed-loop vibrating system of high quality consisting of a cylinder shell resonator, exciting coil, pick-up coil, and amplifier circuit. The paper covers the main research. Firstly, by means of finite element analysis, the cylinder shell is analyzed in Static Analysis, Modal Analysis. Secondly, the cylinder shell resonator is designed and manufactured.Thirdly, The closed-loop oscillating method based on microcomputer, and experiments show it can work well in the lab. The method of calibration under different temperature and compensation for the temperature online is brought forward. The influential factors on the vibration of the cylinder shell resonator are analyzed. The uncertainty in measurement of the transducer at 20 degree is indicated. Through the experiment, the reliable and practical transducer attains 0.4 accuracy.