超音波導管應用於矩形槽之動態液位測量

Abstract

本研究選用氣體作為超音波傳聲介質，由於使用的換能器屬於自發自收式，超音波在傳遞時，彼此之間會互相干擾，以至於在收取信號時波包會互相重疊，造成誤判，在沒有回波放大電路下，很難清楚的接收到回波，故使用多個壓克力導管作為屏蔽，引導自發自收之換能器各自測量液位高度，同時利用機構上的改變，使回波能量放大，以至於可接收到回波信號。在液面靜止下，可藉由壓克力導管機構量測液面的傾斜角度反推當下的液面位置，且液面在線性的晃動下，也可透過液面晃動歷程，量測出平均液面高度，精度達到±2.2%以內，於低成本下，可達更精確、更穩定的量測結果，長時間運作與更廣泛的應用。

This study uses gas as the ultrasonic sound transmission medium. Since the transducers used is pulse-echo, the ultrasonic waves interfere with each other when they are transmitted. So that when the signal is received, the wave packets will overlap each other, causing misjudgment. It is difficult to clearly receive echoes without an echo amplifier circuit. Therefore, multiple acrylic tubes are used as shields to guide the self-receiving transducers to measure the liquid level. At the same time, the change of the mechanism is utilized to amplify the echo energy so that the echo signal can be received. When the liquid level is stationary, the current liquid level position can be reversed by measuring the inclination angle of the liquid surface by the acrylic tube mechanism. If the liquid level is under linear shaking, the average liquid level can be calculated through the sloshing process of the liquid surface. The longitude can reach ±0.5cm or less, and the measurement result can be more accurate and stable at low cost. Operates with a wider range of applications.