高精度多声道超声波密度计

摘要

The propagation speed of ultrasonic wave is affected by the medium’ s density when propagating in the medium.A high accuracy multi-channel densimeter was designed on the basis of this characteristic.The high accuracy measurement of the measured medium’ s density was realized indirectly by measuring the propagation speed of ultrasonic wave.The high resolution and fast signal collection circuit and the digital subdivision algorithms made the measurement of the ultrasonic wave propagation time reach nanoseconds, making sure that the ultrasonic densimeter can realize high-precision density measurement with the resolution better than 10 g/m3 .In the design, the measuring probes were distributed.Several couples of measuring probes were uniformly placed on the outer wall of vessel which was contained with the measured medium, and this design was conducive to make the measurement results more accurate and reliable.%当超声波在介质中传播时，其传播速度受介质密度的影响。基于此种特性，设计了一种高精度的超声波密度计。通过测量超声波在介质中的传播速度来间接实现被测介质密度的高精度测量。由于采用了高分辨率和高速度的信号采集电路以及数字细分算法，使超声波传播时间的测量达到ns级，为超声波密度计实现测量分辨率优于10 g／m3的高精度密度测量提供了保障。设计中采用分布式测头，将多对测头均匀布置在装有被测介质的容器外壁，使测得容器中被测介质的密度更加准确可靠。