沉降过程超声成像传感器制作及其声场测量

摘要

在沉降过程超声成像系统中,工作于液态环境传感器的设计与制作质量直接决定投影数据的采集精度.根据超声波传播理论、压电陶瓷材料的谐振特性和圆形检测场的要求,制作了柱面形且尺寸满足成像要求的压电传感器.根据位相跟踪法,测得传感器的谐振频率在200kHz附近,谐振等效电阻在460Ω左右；发射传感器的发射角度达62°；接收传感器的接收电压达到百毫伏数量级.实验结果表明:接收传感器灵敏度高；发射传感器的发射角度大,声场范围充满了圆形检测场；通过合理控制激励电路的发射功率,声场中无反射波产生,使测量数据具有良好的稳定性.%In the ultrasonic imaging system for settlement process,both design and production quality of ultrasonic sensor for liquid environment can determine the accuracy of projection data collection.Cylindrical piezoelectric sensors of reasonable size were made according to the ultrasonic propagation theory,and the resonant characteristics of piezoelectric ceramic materials as well as the requirement of the circular detection field.Basing on phase tracking method,the sensor resonance frequency can be found at about 200 kHz and resonance equivalent resistance at about 460 Ω; and the launch angle of sensor is about 62° and the output voltage that sensor received can reach hundreds of mV.The experimental results show that the sensor's launch angle is bigger,and with the ultrasonic launching range,the circular detection fields can be found; the reasonable launching power of driving circuit can eliminate the reflection wave in sound field to benefit data stability measured.