With the development of global energy towards low-carbon direction, hydrogen, as a clean secondary energy and energy storage medium, is regarded as the most promising energy source in the 21st century. Gas Ultrasonic Flowmeter is an instrument for measuring gas flow rate, usually installed in gas pipelines to measure the amount of gas flowing through. The gas ultrasonic flowmeter calculates the gas flow rate based on the principle of time difference method by measuring the time difference between the emission and signal reception of ultrasonic waves from upstream to downstream or from downstream to upstream of gas flow, and then calculates the gas flow rate.
At present, the time difference method gas ultrasonic flow meters on the market mostly adopt a layout of a pair of flow meter probes that are obliquely inserted into the fluid channel. By reducing the angle between the probe signal emission direction and the fluid flow direction, the effective ultrasonic signal propagation time difference can be increased, or by increasing the distance between the two probes, the effective propagation time difference can be increased.
However, these two methods inevitably require an increase in the length of the flow meter tube, and for small-diameter ultrasonic flow meters, it is impossible to increase the effective time difference by reducing the angle. If a reflective layout is used, each reflection will reduce the energy of the ultrasonic beam, increasing the difficulty of ultrasonic wave detection. In addition, due to the fact that the sound velocity in hydrogen is approximately four times that of fuel gas or air, and the acoustic impedance is one-quarter that of air, the high sound velocity increases the inaccuracy of flow measurement and leads to poor conductivity of ultrasonic signals, resulting in a decrease in signal-to-noise ratio when measuring hydrogen gas flow rate with conventional gas ultrasonic flow meters, making them susceptible to noise interference and a decrease in measurement accuracy.
MEZOLEN has applied for a patent technology for the installation structure of hydrogen flow meters, which has been first published and authorized. The main functions of this patent are to enhance the practicality of the product, improve the anti-interference ability and sensitivity of the flow meter, and improve the measurement accuracy of the flow meter.
This utility model patent relates to the field of ultrasonic flowmeter technology, particularly to a small caliber ultrasonic hydrogen flowmeter installation structure, comprising a shielding box, a measuring pipe section arranged inside the shielding box, and an ultrasonic flowmeter head arranged on the upper part of the shielding box; The measuring pipe section includes a connected intake pipe, an exhaust pipe, and a direct current pipe.
The intake pipe and the exhaust pipe are symmetrically connected to the upper left and right sides of the direct current pipe. The intake pipe and the exhaust pipe respectively pass through the side walls of the shielding box and connect to the external hydrogen pipeline. The two ends of the direct current pipe are respectively equipped with measuring branch pipes extending along its axis.
The measuring branch pipe is tightly plugged with a flow meter probe, and the flow meter probe is electrically connected to the ultrasonic flow meter head. This utility model patent is suitable for measuring flow rates with small diameters, reducing noise and electromagnetic interference, improving the accuracy of measuring hydrogen flow rates, and effectively solving the technical problem of existing gas ultrasonic flow meters not being suitable for measuring flow channels with small diameters and low measurement accuracy.
