密闭容器内两相液体的液位测量

Level detection of two-phase liquid in sealed container

以密闭容器内油、水液位为检测对象,设计一种基于互相关算法的超声波液位测量系统.以C8051F120为系统的控制核心,硬件架构主要包括超声波收发电路、回波信号调理电路等.采用互相关算法从强噪声中提取回波信号,计算出互相关函数峰值所对应的渡越时间,从而测出油、水液位.在上位机,通过Visual Basic界面调用Matlab的动态链接库来实现互相关函数处理噪声干扰,提高有用信号的识别率.实验结果表明:该系统的测量精度控制在1%左右,并且具有实现简单、稳定性较高、重复性好等特点.

Liquid level of oil and water in sealed container as detecting object, an ultrasonic level measurement system based on the cross-correlation algorithm is designed. Taking C8051F120 as control kernel, the hardware architecture is mainly composed of ultrasonic transmitting and receiving circuit, weak echo signal conditioning circuit and so on. The echo signal is extracted from strong noise by cross-correlation algorithm. Oil and water level are measured through calculating time of flight in accordance with the peak of cross-correlated function. In the upper computer, the dynamic link library of Matlab is called by Visual Basic interface to realize the pocessing of noise interference and improve the recognition rate of useful signal. The experimental results show that the measurement accuracy of the system can be controlled at around 1% , and the system has the characteristics of simple realization, high stability, good repeatablity, etc.