The principle of ultrasonic open channel flowmeter and the performance of measurement advantages.
The basic principle of ultrasonic laser ranging of ultrasonic open channel flowmeter is: according to the ultrasonic sensor installed on the weir (slot) flow measurement equipment, the single-chip microcomputer in the open channel flow meter is designed to output a certain frequency electronic signal to encourage piezoelectric crystallization in the probe Send an ultrasonic data signal of a special frequency, and start a timer at the time of sending and just start to count the time. The ultrasonic data signal is spread according to the measured liquid substance and hits the standard pole. Among them, a part caused the first reflection echo, and a part spread in the water again. A part of the reflection spreads in the reverse direction and enters the probe, causing the probe chip to oscillate, causing the conversion of sound, mechanical kinetic energy, and electromagnetic energy to make the probe output the first electronic signal. When the ultrasonic wave spread again in the water reaches the water surface, because there is vapor (gas) above the water surface, it causes a second reflection echo in the vapor-liquid interface layer, and the reflected echo is scattered and reflected back to the piezoelectric crystal. The probe outputs another electronic signal. That is, the first reflected echo is caused on the reference surface (standard rod), and the second reflected echo is caused on the vapor-liquid interface layer. When the probe receives the reflected wave, it immediately terminates the timing. At this time, the timing is recorded. The device records the propagation time t of the ultrasonic wave from sending to receiving. And t, according to the formula H: ht/t0, (h is the height-width ratio of the top of the weir (trough)) is the aspect ratio of the open channel flowmeter probe to the liquid level H.
Non-contact accurate measurement: The sensor does not touch the liquid, and will not be eroded and contaminated by wastewater. The sensor is a sealed ABS shell structure, which is resistant to alkalis and corrosion, and can be operated for a long time in a humid and cold natural environment; Immediately measure the fluid water surface: The sensor immediately measures the liquid level meter of the fluid water surface. It does not use static wells, which can avoid blocking the connecting pipe due to the application of static wells, suspended solids in wastewater, fine sand, etc., resulting in static wells and measuring weirs The tank water level line is inconsistent, or due to freezing in winter, a false alarm level meter is generated, which causes incorrect flow measurement; Universal adaptability: Set the main parameters of the instrument panel according to the keyboard, which can be applied to various water measuring weirs. Different application standards such as integration into soil irrigation canals and underground concrete pipes;
Detailed service support: Any document shows the installation method of the instrument panel, the basic parameter method, the structure and installation method of the water measuring weir, and the measurement and verification method of the total flow deviation; Reliable quality: After years of manufacturing, operation, and soundness of ultrasonic open channel flowmeters, on-the-spot applications have confirmed that the characteristics of the product meet the requirements for wastewater measurement and verification.