SU113470A1 - Method and device for measuring small flow rates of liquids - Google Patents

Description

At present, various dynamometer tubes such as the Pitot tube are used to measure the flow rates of liquids. All of these instruments measure the instantaneous velocity, which, due to the pulsation of the fluid, can actually differ from the average velocity of the fluid at a given point.

Known devices are less suitable for measuring small fluid flow rates, since. give unsatisfactory readings.

The proposed method and device for its implementation provide the accurate measurement of small flow rates of liquids, make it possible to directly determine the difference between the volumes of liquids flowing through the static and dynamic nozzle of the velocity head tubes and allow periodic filling of the measuring tanks with liquid.

The essence of the invention is that the flow rate is determined with the help of tubes of a velocity head according to the difference in volumes of water OR a different fluid flowing for a certain period of time through the static and dynamic nozzles of these tubes.

To implement the proposed method, a device is used, equipped with two equal in volume and installed at the same level tanks, communicating through a two-way valve of the clamp with a high-speed head, and a feeding tank communicating through a two-way valve with the indicated reservoir.

The drawing schematically shows a device for measuring small flow rates of liquids by the proposed method.

The device consists of two identical tanks U and 2, connected through a two-way valve 3, and tubes 5 with tubes of velocity head 7 and 8, ending with static 9 and dynamic 10 nozzles.

To periodically fill the measuring tanks 1 and 2 with liquid, a feed tank 4 is placed above them, communicating with these tanks through a two-way

crane. The tubes 5 are provided with taps 6 for draining the remaining 51 volumes of water into the measuring burette //.

To measure the flow rate, the instrument is installed above its level at a certain height, depending on the range of measured velocities. The nozzles 9 and 10 are lowered into the notes to the required depth (at the point of measurement of the velocity of the fluid). Water is poured into the tank 4 and the system is filled through a two-way valve 3. Then open the two-way valve and drain the water from one tank to the mark in the pipe 5.

Through the valve 6, the water remaining in the space from the level of the tag to the level of the two-way valve 3 is collected into the measuring burette 11. Then the same operation is performed to drain the water from the other tank and the remaining water is also collected into the measuring burette.

The flow velocity is judged by its dynamic head, determined by the difference of two volumes of water collected in the measuring burettes.

The differences in water volumes are easily measured with greater accuracy and by the results compared with the calibration tables, and the actual value of the flow velocity is determined.

Subject invention

Claims (3)

1. A method for measuring small flow rates of liquids using velocity head tubes, from flow 11 and so that, with an increase in measuring accuracy, the velocity is determined by the differences in the volumes of water or other liquid flowing over a certain period of time. time through static; o and dynamic nozzles of the specified tubes. 2. A device for carrying out the method according to claim 1, characterized by a tel1, which, for the purpose of directing the difference between the volumes of liquids flowing through the static and dynamic nozzles of the velocity head tubes, is equipped with two tanks of equal volume and installed at the same level, Aimi through double-track specks with tubes of velocity pressure. 3. The device according to claim 2, in connection with the fact that, in order to periodically fill the measuring stations with a liquid, the liquid was supplied with a supply tank communicating through a two-way valve with the indicated reservoirs.