SU1744528A1 - Device for measuring pressure pulsations on river floor - Google Patents

Abstract

The invention relates to hydrometric work on rivers and is intended to measure pressure pulsations at the bottom of river streams. The pressure sensor with a membrane 2 is mounted on a rod in the form of a pipe 5, which is sealed at the other end, carries a sealed container 4 and has a fitting 8 for supplying air under pressure. When the sensor is installed at the bottom of the river, the pipe 5 is filled with water through the opening 9, after which the water is squeezed with air to the opening 9. The air pressure in the pipe 5, corresponding to the water pressure on the membrane 2, is distributed through the pneumatic line 6 into the tank 4 and through the pneumatic line 3 into internal cavity of the sensor. After shutting off the valve 7, the pulsations are measured. All this allows to increase the accuracy and reliability of the measurement. 1 il.

Description

The invention relates to techniques for hydrometric work on rivers.

A known hydrostatic pressure transducer containing an immersible membrane sensor with a cylindrical body connected by a pneumatic conduit with a sealed elastic container.

The disadvantages of the known device are the occurrence of additional pressure pulsations in the measuring system due to fluctuations in the elastic capacity, which reduces accuracy, as well as the possibility of damage to this capacity by the flow.

The purpose of the invention is improving accuracy and reliability.

This goal is achieved by the fact that in the device for measuring pressure pulsations at the bottom of the river stream, containing an immersible membrane sensor with a cylindrical body, the inner cavity of which is connected by a pneumatic conduit to a sealed container, the pneumatic conduit is enclosed in a pipe, one end of which is attached to the outer surface of the cylindrical sensor housing and the other is sealed, while the pipe is equipped with a fitting for supplying excess pressure, connected through additional pneumatic pipe and valve with a sealed container and has an outlet located in a plane coinciding with the sensor membrane.

The drawing shows a diagram of a device for measuring pressure pulsations.

The device comprises a membrane sensor 1 with a cylindrical body, the membrane 2 of which is located horizontally at the level of the surface of the bottom of the river flow. The internal cavity of the sensor is connected by a pneumatic pipe 3 with a sealed container 4 having rigid walls. The pneumatic pipe 3 is located concentrically in the pipe 5, which performs the function of a rod carrying a membrane sensor 1, to the side surface of which it is attached at one end.

The other end of the pipe 5 is closed and carries a sealed container 4, the inner cavity of which is connected by an additional pneumatic conduit 6 and valve 7 to the inner cavity of the pipe 5. On the pipe 5 there is a nozzle 8 for supplying excess pressure and an outlet 9, which is located in a plane coinciding with the membrane sensor.

The device operates as follows.

In the section of the river where it is necessary to measure the characteristics of pressure pulsation at the bottom of the channel, the device is lowered vertically under water and pressed into the bottom until the membrane 2 is level with the surface of the soil. After immersion of the device, water through the hole 9 enters the cavity of the pipe 5 and is installed at the water level in the river. After that, air is injected into the nozzle 8 under pressure, which fills the pipe 5, enters the tank 4 and from it into the cavity of the sensor 1. Air displaces the water from the pipe 5. The pressure in the cavity of the sensor 1 rises. As soon as the water level reaches the hole 9, the air from the pipe 5 goes outside, and the pressure in the cavity of the sensor 1 will cease to increase. The moment of air exit from the hole 9 is detected by air bubbles on the surface of the river stream. At this moment, close valve 7 on the air line 6. Thus, the pressure in the container 4 and in the cavity of the sensor 1 are equal to each other and the water pressure on the surface of the membrane 2, since the hole 9 is located at the level of the membrane. The pressure equality is maintained throughout the experiment due to the volume of air in the tank 4. After the pressure inside the cavity of the sensor 1 is compared with the water pressure at the level of the membrane 2, the pressure pulsation is measured.

This design of the meter of pressure pulsations has a higher measurement accuracy due to the use of the tank 4 with rigid walls that do not allow distortion of the pressure pulsations, and has increased reliability by eliminating the possibility of damage to the walls of this tank by the river flow.

Claims (1)

Claim A device for measuring pressure pulsations at the bottom of a river stream containing a submersible diaphragm sensor with a cylindrical body, the internal cavity of which is connected by a pneumatic conduit with a sealed container, characterized in that, in order to improve accuracy and reliability, the pneumatic conduit is enclosed in a pipe, one end of which is attached to the outer surface of the cylindrical body of the sensor, and the other is sealed, while the pipe is equipped with a fitting for supplying excess pressure, connected through an additional pneumatic conduit and in An airtight container with an outlet and located in a plane that coincides with the sensor membrane.