SU913260A1 - Ionization anemometer - Google Patents

Description

The invention relates to experimental meteorology and can be used to study the dynamics of a gas flow, for example, in wind tunnels.

Known acoustic anemometers containing emitter and eight receivers located in the corners of a rectangular parallelepiped. The flow rate is measured by the phase difference between the sent downstream and upstream flow oscillations. Comparison of the phase shift between different receivers allows us to determine the gas flow velocity vector [1].

The disadvantage of acoustic anemometers is their sensitivity to vibrations and acoustic noise.

Also known ionization anemometer containing amplifying system and ionization sensor. The device is placed in a gas stream. Between the electrodes of the sensor create an electric field. At the receiving electrodes

2

there is a difference of signals, which determines the gas flow rate in the direction from one receiving electrode to another C2).

The disadvantage of this anemometer

⁵ is the low measurement accuracy of the three-dimensional gas flow velocity vector.

The aim of the invention is to improve the measurement accuracy of three-dimensional

¹⁰ vector gas velocity.

This goal is achieved by the fact that in the ionization anemometer, containing "amplifying system and

¹⁵ Ionization sensor, the sensor is made in the form of a sphere that is transparent to a gaess stream, covered with a radioactive preparation from the inside, while at the center of the sphere there are at least six electrodes equidistant from each other and connected to the amplifying system through a switch.

3 9132

FIG. 1 and 2 shows the proposed device.

The device includes electrodes 1 located on insulator 2 and placed in sphere 3 with radioactive coating on the inner surface. Electrodes 1 are connected via switch 4 to preamplifier 5 and differential amplifier 6.

The device works in the following 10 ways.

Radiation from a radioactive isotope, for example, ^ 1, ionizes the gas between sphere 3 and electrodes 1. Between sphere 3 and electrodes 1, an electric field is created. At the electrodes 1, current signals are generated that enter the switch 4. In the absence of gas movement, the distribution of ions between each of the electrodes 1 20

and sphere 3 is the same, so all current signals are equal. Under the action of the gas flow, the distribution of ions inside sphere 3 changes, which leads to the appearance of the difference between these signals. The velocity vector V is determined by three successive measurements of the projections of the velocity vector of the flow on the axis of an arbitrarily oriented coordinate system with a point of reference at the center of the sphere \ / χ, 14 ^, ^ 2 1 / ⁼ V * + / c + ΐ / χ. Each of the projections of the flow velocity vector is determined by a difference signal between interconnected switch 4 electrodes 1 of the upper (positive semi-axis selected for this dimension axis) hemispheres and interconnected switch 4 electrodes of the lower hemisphere (negative semi-axis). The signal corresponding to the projection of the century 0 4

the speed of the torus to another axis is formed after the corresponding switching of the switch contacts When selecting a rectangular coordinate system, the absolute value of the speed

flow v =.

Use of this device

increases the accuracy and reliability of measurements, and its mechanical strength, vibration resistance, the ability to work at low pressures (up to several mbar) can be used when measuring ’in wind tunnels, when installing an anemometer on moving objects.

Claims (1)

Claim An ionization anemometer containing an ionization sensor and an amplifying system, characterized in that, in order to improve the measurement accuracy of the three-dimensional vector of the gas flow velocity, the sensor is designed as a sphere transparent to the gas flow, covered inside with a radioactive preparation, at least six electrodes, equidistant from each other and connected to the amplifying system through a switch.