时差法在超声波气体流量计中的应用研究  

Applied Research on Time Difference Method in Ultrasonic Gas Flow Meter

作　　者：王民意[1] 钟新跃[1] 

机构地区：[1]长沙师范学校电子信息工程系,湖南长沙410100

出　　处：《仪表技术与传感器》2013年第7期26-28,共3页Instrument Technique and Sensor

基　　金：湖南省高等学校科学研究项目(11C0099)

摘　　要：为了提高小管径煤矿瓦斯抽采管道的气体流量测量精度,基于时差法测量原理设计了超声波气体流量计,采用一对40 kHz的收发一体式超声波换能器作为发射和接收元件。以74HC00与非门设计的推挽式超声波驱动电路实现了低压驱动超声波换能器,并用集成红外遥控接收芯片CX20106A和单稳态触发器4013构成了信号调理电路,实现了对固定波形的稳定检测。利用高精度的时间数字转换芯片TDC-GP21作为计时芯片,实现了极低风速的测量。实验测试表明:设计的硬件电路具有良好的性能,测量风速分辨力可以达到0.1 m/s,提高了气体流量的测量精度。In order to improve the measurement accuracy of gas flow in the small diameter coal mine gas drainage pipes, the ultrasonic gas flow meter based on time difference method was designed with one pair of 40 kHz transceiver integrated ultrasonic transducer as the transmitting and receiving components. The NAND gate was used to make a push-pull ultrasonic drive circuit which got a low-w^hage drive ultrasonic transducer, and the signal conditioning circuit was composed of the infrared remote control receiver CX20106A and single shot trigger 4013 which implemented the stability of the detection of the fixed waveform. The preci- sion time-to-digital conversion chip TDC - GP21 as the timer achieved the measurement of very low wind speed. The experiments show that the hardware circuit possesses a good performance whose wind speed resolution can reach less than 0.1 m/s and greatly improve the accuracy of the gas flow.

关 键 词：时差法测量 超声波气体流量计 硬件电路 

分 类 号：TB216[一般工业技术—工程设计测绘]