The difference between single and double channels for ultrasonic flowmeters
If more accurate, multichannel measurements can meet requirements. In addition, the electromagnetic flowmeter adopts area measurement, which is more reliable. But in the large bore measurement, the installation cost of electromagnetic flowmeter is very expensive, in addition, electromagnetic flowmeter must be external power supply is also a trouble. Ultrasonic instrument is relatively cost-effective, and can get rid of the power and downtime problems, process measurement is not as a standard table, the individual feel of the basic ultrasound can meet the requirements.
The flow of fluid in the pipeline is very complex, according to the text in the description of fluid mechanics and related experimental data, the liquid velocity curve in the pipeline should be bullet shape, namely: middle high velocity, low peripheral velocity. A single channel instrument measures a line across a cross-section of a pipe, the velocity measured on this line represents the velocity of the entire cross sectional area. Thus measuring the flow of the pipe. When the pressure is small, the flow rate is low, and the performance of the instrument is good, the measurement error is small. Basically meet process measurement. When the flow velocity is slightly faster and the straight pipe section is not good, the single sound error will be great. The double channel can measure the flow velocity in another direction, and this error makes the measurement closer to the true value. That is to say, the error is relatively small. And the cost is more economical.
