SU607462A1 - Method of measuring vortical component of sea current velocity - Google Patents

Description

(54) METHOD OF MEASUREMENT OF VORTEX COMPONENTS OF MARINE FLOW RATE

The invention relates to the field of oceanographic measurement technology and can be used to register various eddy disturbances in a liquid medium, in particular for measuring the eddy component of the velocity of sea currents.

Earlier, attempts were made to determine the vortex component rotV by separate measurements Y at several points (with the subsequent calculation,. Avy 9V,

,; aVy 9V, 4

But it is not

by goth

 y

is a direct measurement of roiV.

Methods are known for measuring the flow rate, based on radiation of ultrasonic vibrations along open lines in two opposite directions to and from the flow and measuring the time difference or phase of these oscillations, which is a measure of the flow rate of the liquid AND

However, all these methods allow .. to define only a certain component of the velocity V.,. Due to the fact that in the known methods the principle of sending signals back and forth

along open lines, it is impossible to directly measure the vortex component of the PotV velocity, which must necessarily contain information about the processes in the flow area under study.

The closest to the invention in its technical essence is a method for measuring the flow velocity of a river, according to which the flow is measured using three ultrasonic transducers, the second of which is located on one side of the river, and the first and third are on the other side. Ultrasonic vibrations are sent from the first and third transducers to the second and in the opposite direction, respectively, to the third or to the first transducer. Additional excitation of the first and third transducers is provided so that they become, respectively, emitters or oscillation receivers. In this case, the sum and difference of the transit time of the ultrasonic vibrations from the first to the third transducer and the transit time of the signal from the third to the first are measured. The sum and difference of this time determine the speed of the flow of the river 2 | .

Although this method does not exclude large-scale measurements, by virtue of the use of the principle of linear measurements, it is not possible to determine directly the vortex component of the flow velocity.

The purpose of the invention is the provision of the possibility of large-scale direct measurements of the vortex component of the flow velocity.

This is achieved by the fact that, according to the proposed method, ultrasonic oscillations are directed in a closed loop covering the flow area under study,

The essence of the proposed method is illustrated in the drawing.

At point A (0,0), with which the beginning of the rectangular coordinates is combined, a non-directional source of ultrasonic vibrations is located on the surface of the marine environment. At a given distance at point B (S, 0), a repeater is installed, which receives the oscillations received from point A and immediately radiates them again, for example, at another frequency or with some known delay, which can be taken into account. Similar transponders, accepting and radiating vibrations, are installed at points C (, B) and O (O,). In-point A there is also a measuring device, with which the time t is determined, which will be required for the acoustic signal to pass along the closed loop ABSTE A. After this, the repeaters start working in reverse order; From point A, ultrasonic vibrations are emitted, which are received and reproduced by ID transponder, then by transponder C, then by transponder B. In this case, the measuring device at point A determines the time i2, which is necessary for the acoustic signal to bypass the same circuit, but in the opposite direction, i.e. along the path ABCS A, In the drawing, the forward and reverse directions of propagation of oscillations along the contour are indicated by solid and dashed streaks, respectively.

Ш1)

f {i.i)

The difference between the measured times 51 C is a measure of the average velocity of the currents V (x, y) in the throat component over the area 6 of the given ABCBA contour, which covers the next-flow area, namely, the average intensity of the vortex component cotglF "cCSty where is the well-known coefficient, which is Constant and determined by the dimensions of circuit 2 and the average sound velocity YO.

The measurement results will be the more accurate, the larger polygon (by the number of sides) is the contour covering the flow area under study. Tov. the greater the number of repeaters.

Practically, the described method of measurement can be carried out, for example, with the installation of four or more in a sea. From the main buoys with the source and retransmitters of ultrasonic vibrations. The mechanical oscillations of the buoys themselves do not play a significant role, since the distances K are long enough, and the time of each measurement cycle is short, and, if necessary, the subsequent averaging of the obtained samples over a time longer than the oscillation period of the buoys is possible.

Claims (2)

Invention Formula A method for measuring the vortex component of the velocity of sea currents by emitting ultrasonic oscillations in two opposite directions and measuring the propagation time of these oscillations, characterized in that, in order to provide the possibility of large-scale direct measurements of the vortex velocity components, / ultrasonic the oscillations are directed in a closed loop, sweeping the flow area under investigation. Sources of information taken into account in the examination: 5 1. Copyright certificate. USSR №252746, cl. Q 01 P 5/00, 09.22.69. 2. Patent of Japan. 45-40356, class 111 A 1, 11.12.70.