RU2071596C1 - Method of determination of depth of reservoirs and level of liquid and device for its implementation - Google Patents

Abstract

FIELD: measurement technology. SUBSTANCE: self-sufficient single-use probe having temporary buoyancy, provided with energy content and emitting radiation and desk which is receiver of radiation and calculator of sought-for values are provided for measurement of depth of reservoirs and level of liquid. For implementation of method probe is thrown into reservoir, time of start of its movement and moments of change of radiation parameter related to reach by probe of level of liquid and/or bottom of reservoir are registered, time intervals spent for fall and submersion of probe and transmission of radiation in medium are found and sought-for values are calculated in compliance with number of changes of radiation parameter by specific formulas. Designs of device for realization of method in general case and in case of examination of reservoir with optically transparent liquids are described in formula of invention. EFFECT: improved authenticity of method, enhanced functional efficiency of device for its implementation. 4 cl, 3 dwg

Description

 The invention relates to techniques for remote measurements of distances in gaseous and liquid media to their interfaces and interfaces with the solid phase. It can find application in the chemical and oil industries, in geology, in mining (for example, when examining vertical blast holes) and in other sectors of the economy in those cases where rapid single measurements of tank depth and liquid level are required using portable portable equipment with low energy costs.

 Known methods and devices for determining the level of liquids and granular media in various technological and natural containers (tanks, bunkers, wells, natural reservoirs, etc.), for measuring depth and examining the surface condition of such tanks, as well as for joint solution of such problems , in particular determining the position of the bottom of the well and the level of water or other liquid in it. These methods and devices are divided into two main types: contact, which is based on measuring distances using devices that are lowered (inserted) into the tank and having a length greater than or equal to its depth, and non-contact (remote), in which measuring operations are reduced to registration and processing of the radiation emitted by the device and reflected from the phase boundaries (from the surface of the liquid or the bottom and walls of the tank).

 For example, to measure the liquid level and depth (bottomhole position) of wells, a device with temporary buoyancy is used, hollow cylinders with holes and a valve [1] This device is lowered into the well on a cable whose length is obviously greater than the depth of the well and is controlled during reeling from the drum winches. At the moments when the liquid level is reached and, then, the bottom of the well, the cable tension is weakened, which serves as a signal for taking the cable length count, that is, for determining the desired values. Such a device allows for one descent into the tank (well) to measure the liquid level and the distance to the bottom (bottom). However, it also has drawbacks, such as the bulkiness and complexity of the contact system, including the descent vehicle, cable, winch, etc. the need for large expenditures and time for hoisting operations, etc.

 In non-contact methods and devices for determining the level of liquid and granular media in tanks, measuring depth and examining the state of the latter, electromagnetic radiation of a different nature in the microwave or optical range, acoustic, etc., are used.

 It is known, for example, an acoustic device [2] which allows by measuring the time intervals from the moment of sending a probe pulse to the moment of arrival of reflected signals, as well as by analyzing the shape and polarity of these signals to determine the depth of the wells, the presence and type of defects on their walls. With the help of such a device, it is possible to solve the indicated problems without introducing measuring devices into the object, that is, contactlessly, very quickly and accurately, but this requires the sending of sufficiently powerful probe pulses, which is associated with high costs and, as a result, using relatively bulky and massive equipment. In addition, the device is not protected from interference (random acoustic impulses that occur in the earth's crust during stress unloading) and does not allow determining the depth of the well in the presence of fluid, since the probe radiation partially reflects from the liquid / air interface, partially passes through it and then almost completely absorbed.

 Known methods and devices operating on the principle of location of electromagnetic waves in the microwave range [3] have much better protection against interference, since there are no extraneous signals in this wave range in most cases. Interference, for example, when determining liquid levels, can only be reflected from the surface roughness of the reservoir wave. The disadvantages of such devices include the fact that they can only be used to determine relative changes in level if special devices are not provided for them, in particular calibration cascades, as was done in [3]. Introduction of calibration devices complicates the design of devices, increases their dimensions and mass. However, the main factor on which such characteristics of the equipment depend is the need to use powerful probe radiation. As well as acoustic, microwave level meters do not allow to determine the depth of the tanks in the presence of liquid.

 The closest in technical essence to the described invention is the level measurement method described in [4]. Like in [3], this method applies the principle of electromagnetic radiation location in the microwave range, but the resulting interference pattern changes over time, because “backward” waves are used, reflected not by the boundaries (bottom) of the reservoir or the liquid filling it, but by the incident passive reflector. The number of interference extrema that occur when the reflector falls is proportional to the depth of the fall, so this method allows you to determine the desired distance (depth, level) directly, without calibration, etc. fixtures. The noise immunity of this measurement principle is much higher, because the waves reflected from the fixed boundaries give an invariable interference pattern over time, which does not affect the results of determining the desired quantities. However, this method, like all others described above, is associated with large energy costs. This is due to the fact that when passing the path from the transceiver to the reflecting surface and back, the radiation is scattered twice and absorbed and reaches the mixer very attenuated, therefore, in order to reliably obtain the interference pattern, it is necessary to amplify the received signal or increase the power of the probe radiation many times. Both that, and another leads to increase in energy consumption, the mass and dimensions of the equipment. In addition, like other methods based on echo location, it does not allow determining the depth of reservoirs containing liquid, because the probe is partially reflected by the surface of the liquid, partially absorbed in it.

 The aim of the invention in terms of the method is to remotely obtain information about the liquid level and the depth of the tank in one measuring cycle and reduce the cost of energy and time for the implementation of the procedure for determining the desired values. At the same time, the task is to develop such a method, it could be implemented using portable portable measuring tools in the case when single definitions of depth and level are required, for example, when examining vertical blast holes.

при V_u>V,

при V_u≈V,

где L глубина резервуара;
X уровень жидкости или отметка дна пустого резервуара, отсчитываемые от точки старта зонда;
h высота столба жидкости в резервуаре;
m масса зонда;
m_o= βVρ_o присоединенная масса;
α эмпирический коэффициент, учитывающий аэро- и гидродинамические качества зонда и свойства среды;
b численный коэффициент, зависящий от геометрической формы зонда;
V объем зонда;
r_o плотность среды, в которой движется зонд;
ρ средняя плотность вещества зонда;
V скорость движения зонда;
V_н скорость распространения излучения в среде;
g ускорение свободного падения;
T, T₁=const время изменения регистрируемого параметра излучения при достижении зондом границ раздела газ/жидкость, газ/твердое тело (T), или жидкость/твердое тело (Т₁);
T_Σ= t_и1-t₀;
t₀ момент запуска зонда;
t_и1 момент регистрации первого изменения параметра излучения, сигнализирующего о достижении зондом уровня жидкости или дна пустого резервуара;
T_Σ1= t_из-t_и2;
t_и2 момент регистрации второго изменения параметра излучения, сигнализирующего о начале погружения зонда в жидкость;
t_и3 момент регистрации третьего изменения параметра излучения, сигнализирующего о достижении зондом дна резервуара с жидкостью.This goal is achieved by the fact that sensing, including launching (dropping) the probe in the direction of the bottom or the boundary surface of the liquid, receiving and processing radiation, is used, in contrast to the known solutions, not long measuring devices [1] or reflected by the boundaries of the object [2, 3 ] or passive reflectors [4] of radiation, but having a temporary buoyancy, equipped with a reserve of energy and emitting radiation, a stand-alone disposable probe. At start-up, the moment of the beginning of the probe’s movement and then the moment of the change in the parameter of the radiation emitted by it associated with the probe reaching the liquid level and / or the bottom of the tank is recorded. After that, find the intervals of time spent on the fall and immersion of the probe and the passage of radiation in the medium, and calculate the desired depth and level in accordance with the number of changes in the radiation parameter by the formulas:
L = X (1)
when changing the radiation parameter once (tank without liquid),
L = X + h (2)
when changing the radiation parameter three times or more (reservoir with liquid),

for V _u > V,

at V _u ≈V,

where L is the depth of the tank;
X fluid level or bottom mark of the empty tank, measured from the starting point of the probe;
h the height of the liquid column in the tank;
m is the mass of the probe;
m _o = βVρ _o added mass;
α empirical coefficient taking into account the aerodynamic and hydrodynamic qualities of the probe and the properties of the medium;
b is a numerical coefficient depending on the geometric shape of the probe;
V probe volume;
r _{o the} density of the medium in which the probe moves;
ρ is the average density of the probe substance;
V is the speed of the probe;
V _{n the} speed of propagation of radiation in the medium;
g acceleration of gravity;
T, T ₁ = const the time of change of the registered radiation parameter when the probe reaches the gas / liquid, gas / solid (T), or liquid / solid (T ₁ ) interfaces;
T _Σ = t _{and 1} -t ₀ ;
t ₀ probe start time;
t _{and 1} moment of registration of the first change in the radiation parameter, signaling that the probe has reached the liquid level or the bottom of an empty tank;
T _Σ1 = t _from -t _and2 ;
t _{and 2 the} moment of registration of the second change in the radiation parameter, signaling the beginning of immersion of the probe in the liquid;
t and _{3 the} moment of registration of the third change in the radiation parameter, signaling that the probe reaches the bottom of the reservoir with the liquid.

 The combination of these distinguishing features allows to obtain technical results that are the purpose of the invention. In particular, remote sensing of the reservoir depth and liquid level in it becomes possible due to the fact that the probe is autonomous and the stored energy is used to transmit information about its location using the emitted radiation. During movement, the probe travels all the way from the start to the bottom of the tank, regardless of whether there is liquid in the latter or not. At the same time, the probe signals a change in the parameter of the emitted radiation that it has reached the phase boundaries at certain times. This allows you to determine the depth of the tank and the liquid level in one measurement cycle. Since the probe moves in the tank under the action of gravity, energy is not required. It is spent only on the emission of the probe radiation, as well as on the reception and processing of this radiation on the remote control. Therefore, the energy consumption in this method is significantly less than, for example, when using contact devices with hoisting operations, or in the echo location. Since sounding is carried out remotely, the time spent on the determination of the desired values is significantly less than in contact methods, and closer to the time spent on the echo location. Low power consumption determines the possibility of creating small-sized portable equipment for implementing the method, and the use of a disposable autonomous probe in its composition makes it advisable to use such equipment for single measurements.

 To implement the method described above and in order to simplify the design, reduce the weight and dimensions of the equipment, increase the information content and accuracy of the measurement results, it is proposed to use a device consisting of a remote control with a power supply and a probe and having the following distinctive features.

 The probe, unlike the known devices [1], is autonomous, i.e. communication lines not connected to the remote control (cable, cable, etc.). In addition, it is a radiation source, and not a passive reflector [4], has temporary buoyancy and changes when radiation reaches phase boundaries. These qualities of the probe are ensured by the starting device included in its composition, an energy carrier or an accumulator (source) of energy and a functionally convertible transmitter (emitter), as well as a ballast tank with holes, which keeps the probe afloat until it is filled with liquid. The simplicity of the design and the low cost of the probe allow it to be used as a disposable device.

 The remote control serves to launch the probe, which is carried out practically without energy consumption, and is a passive part of the device as part of the sensing process, which, in addition to the above, performs the operations of receiving and converting radiation and calculations, which differs from the known devices [2-4], which include transmitting horns antennas, etc. that is, elements that perform active operations. To carry out these functions, the remote control includes a starting device, a radiation receiving transducer, a first amplifier, a differentiating cascade, a second amplifier, a pulse shaper, a counting and analyzing device, and a digital indicator. The entire electrical circuit is performed on the elements of modern microelectronics and liquid crystal technology and therefore has low power consumption.

 These distinctive features of the device allow to obtain the necessary technical results. In particular, due to the temporary buoyancy, it is possible to clearly fix the moments when the probe reaches the surface of the liquid and the beginning of its immersion. The ability to change the radiation parameter when the probe reaches the phase boundary allows the use of radiation to remotely transmit information about the location of the probe. Together, both of these probe qualities make it possible to determine both the liquid level and the depth of the tank in one measurement cycle, i.e. increase the information content of the measurement results. In addition, temporary buoyancy allows the immersion of the probe under controlled conditions, namely at zero initial speed, regardless of the height of its fall into the liquid. The fulfillment of this condition provides an increase in the accuracy of calculations of the depth of immersion.

 The autonomy of the probe and its ability to remotely transmit information about reaching the phase boundaries simplifies the design, reduces the weight and dimensions of the equipment as a whole, because there is no need to use powerful transmitting and receiving antennas or tripping mechanisms and power sources that correspond to their energy consumption.

 For a special case of measurements in tanks with optically transparent liquids, it is proposed to use a device with the following distinctive features.

 The probe is made in the form of a rotation elongated along the body axis with density and diameter varying in the longitudinal direction. The centers of gravity of mass and volume are arranged in such a way that, along with the geometric shape of the probe, it ensures its steady rectilinear movement with a longitudinal axis oriented along the motion path, tipping over upon reaching the phase boundaries, and returning to the original orientation due to the displacement of the center of mass of gravity to the center of gravity of the volume and immersion in the liquid when it fills the ballast tank. The probe is equipped with a housing made of an elastic material that is open from one of the ends and has a ballast capacity on the other end, into which a power element is inserted with an interference fit and an optical transducer (emitter) connected to it using a conductor and an insulated base contact. In this case, the active part of the transducer (emitter) is recessed into the housing and faces towards its open end. The probe is also equipped with a starting device, made in the form of a spring clamp with a clamp, in the inoperative state of the probe mounted on the housing at the point of contact of the battery and converter (emitter) and disconnecting them due to the transverse compression of the housing with the formation of a neck and elongation along the axis of rotation.

 The combination of these distinctive features provides the optimal way to achieve the necessary technical results in this particular case. This applies to simplifying the design of the device (probe), reducing its mass and dimensions, increasing the information content and accuracy of the measurement results. This is achieved by using a small number of small-sized standard elements in the design and giving the probe the ability to change the intensity of the radiation directed towards the remote control by tipping it at the phase boundaries.

In FIG. 1 shows an exemplary view of time diagrams that are obtained when implementing the proposed method:
And for the intensity I _{and the} radiation emitted by the probe in the direction of the remote control;
B for the radiation intensity I _p received by the remote control;
In for a sequence of pulses that occur at the output of the differentiating link as a result of reception and conversion of probe radiation by the remote control.

 In FIG. 2, a drawing of a probe for measuring in tanks with optically transparent liquids is made.

 In FIG. 3 is a block diagram of the electrical part of the remote control.

 A separate block shows the starting device (with the probe shown in the same place), which mainly performs the functions of the supporting structural element, but also includes an electric circuit with the device start contact.

 The implementation of the method, for example, when examining tanks with optically transparent liquids, is as follows.

At a fixed point in time t _{0, the} probe is launched (dumped) into the reservoir in the direction of the boundary surface of the liquid. In the gas phase, it moves rectilinearly in the direction of the remote emitting radiation with an intensity I _u0. Upon reaching the surface of the liquid at time t ₁ (see Fig. 1, A), the probe partially or completely immerses in it, capsizes (changes orientation) at time t ₃ and again floats. This leads to a rapid decrease to I $\genfrac{}{}{0ex}{}{\text{(one)}}{\text{ik}}$ the intensity of radiation directed towards the remote control, which is last recorded and converted into a pulse of positive polarity at time t _{and 1} (Fig. 1, B).

где Х₁ расстояние, отсчитываемое от точки старта зонда;
t текущее время.The movement of the probe in gases and low-viscosity liquids under the action of gravity, i.e. falling or immersion, with satisfactory accuracy, is described by the equation

where X _{1 the} distance measured from the starting point of the probe;
t current time.

 Equation (6) is valid for large Reynolds numbers [5], which is the case in practice even when the probe begins to sink into the liquid at zero initial velocity.

 Calculations show that during the movement of a spherical body with a radius of 0.5 cm, which began to sink into water at zero initial speed and passed a distance equal to its diameter (≈1 cm) in water, the Reynolds number is Re≈3000. This condition is fulfilled both at the time of the start of the probe and at the moment of the start of the dive (due to the presence of the temporary buoyancy property of the probe).

приводит к выражению (3) для высоты Х падения зонда в газовой фазе, то есть для уровня жидкости или отметки дна пустого резервуара, отсчитываемых от точки старта зонда.For the case of a probe falling in the gas phase, equation (6) is simplified; the buoyancy force Vρ • g and the attached mass m _o = βVρ _{o are} neglected due to their very small value, which is due to the low density ρ _{o of the} gas Vρ _o ≪ m. Integration of such an equation under the indicated condition (zero initial velocity)

leads to expression (3) for the height X of the fall of the probe in the gas phase, that is, for the liquid level or the bottom mark of the empty tank, counted from the starting point of the probe.

прохождения излучения пути X. Это имеет место при использовании оптического излучения. При V_и≈V в (3) вводится поправка: из T_Σ вычитается T_хи, что после преобразований (3) приводит к трансцендентному уравнению (4) для величины Х.In (7), (8), t denotes an arbitrary time instant. Relation (3) gives an accurate result, provided that the velocity V _{and the} propagation of radiation in the gas are much higher than the velocity V of the probe (V _and > V), i.e. in the case when the interval T _Σ = t _{and 1} -t ₀ does not include time

radiation path X. This occurs when using optical radiation. When V ≈V _and (3) a correction: T _Σ subtracted from T _hee that after transformation (3) yields a transcendental equation (4) for the value of H.

Starting from time t _{1, the} ballast capacity of the probe begins to fill with liquid. This process ends after the probe emerges at time t ₅ and is accompanied by its reverse tipping and the beginning of immersion at time t ₇ (Fig. 1, A). When the probe is inverted overturning, the intensity of the radiation emitted by it in the direction of the remote control rapidly increases to the initial value I and ₀ . This is recorded in the remote control and is converted into a pulse of negative polarity at time t _{and 2} (Fig. 1, B). Upon reaching the bottom of the tank at time t _{9 the} probe again capsizes, while again rapidly decreasing to a value of I $\genfrac{}{}{0ex}{}{\text{(2)}}{\text{ik}}$ intensity of radiation emitted in the direction of the remote control. In the remote control, this causes the appearance of a pulse of positive polarity at time t and ₃ .

При этом учитывается, что скорость V_и1 распространения излучений в жидкостях как правило много больше скорости V движения зонда. В результате интегрирования (6) для h получается выражение (5).To find the immersion depth h of the probe (or the height of the liquid column in the tank), equation (6) is integrated under conditions similar to (7), (8)

It is taken into account that the velocity V _{and 1 of the} propagation of radiation in liquids is usually much higher than the speed V of the probe. As a result of integration (6) for h, we obtain expression (5).

The desired depth L of the tank is determined by the formula (2). In the case of an empty (liquid-free) tank, the probe capsizes once upon reaching the bottom, therefore, pulses are not generated at times t _{and 2} and t and ₃ in the control panel and, when calculating L, h = 0, i.e. formula (1) is used.

 Depending on the design features of the tank, the conditions of the installation site of the console and the properties of the liquid in the tank, radiation of various nature can be used when implementing the method: mechanical vibrations in the sound or ultrasonic range, electromagnetic waves in the optical or other part of the spectrum, etc. In this regard, it is possible to use in the design of the probe and the corresponding converters of energy, its sources or energy carriers.

 In FIG. Figure 2 shows the construction of a probe that emits electromagnetic radiation in the visible (optical) part of the spectrum.

 The probe consists of a housing 1 made of elastic material, such as soft rubber, an energy converter of an incandescent lamp 2, a starting device made in the form of a spring clamp 3 with a clamp and a power source (battery) 4. The lower part of the housing has a hollow pear-shaped thickening 5 with several holes 6, which is the ballast capacity. The empty case (without battery and incandescent lamp) is an elastic tube with a pear-shaped expanded lower part. When assembling the probe, a battery is inserted with an interference fit into the tube with a flexible electrical conductor 7 fixed on its body (negative pole) so that the battery reaches its top part of the pear-shaped extension with its bottom or, if necessary, partially enters it. The incandescent lamp wraps around in several turns of the conductor emerging from the tube and is also tightly inserted into the tube until its base contact touches the positive pole of the power source. In this case, the bulb lights up and the probe is thus brought into working condition. To transfer it to a non-working mode (transport state), a spring clamp 3 is put on and tightened at the place of contact of the battery bulb. The clamp clamps and stretches the tube and thereby removes the bulb from contact with the battery. The light goes out. When the probe is started, the clamp is loosened, the light comes on, the probe is released and begins to fall into the tank.

The buoyancy of the probe is ensured when the average density of its substance ρ is less than the density of the liquid r _o . If the average density of the substance of the power source ρ _o is 2.5 times higher than the density ρ _{o of the} liquid, which is true, for example, for standard dry cells (batteries) and water, then to ensure the buoyancy of the probe (ρ ≈ 0.9ρ _o ) capacity of approximately 2 times the volume of the power source. This is quite acceptable and allows you to create a probe with the necessary dimensions, aerodynamic and hydrodynamic qualities. When the density of the body material ρ _k is close to the liquid density ρ _k ≈ 1.1ρ _o , which occurs, for example, when using soft rubber and the indicated ratio of the volumes of the power source and the ballast capacity, the center of gravity of the probe’s mass Om is located on its axis of rotation slightly lower than the center of gravity of the power source, and the center of gravity of the volume Ov is shifted along the axis lower and closer to the ballast capacity (Fig. 2). Such an arrangement of the centers Om and Ov ensures the tip overturns when it reaches the phase boundary and restores the original orientation at the beginning of the dive due to the displacement of Om to Ov when filling the ballast tank with liquid. The stability of the probe’s movement is ensured by the fact that the lifting force acting on its upper part located above the center of gravity Оm is greater than the lifting force acting on its lower part located below Оm, so that if the axis of the probe deviates from the trajectory accidentally, the incoming gas flow or fluid causes the resulting torque, which restores the original orientation. The required magnitude of the lifting force acting on the upper part of the probe is achieved by increasing the length of the housing (tube) from the side of the energy converter, i.e. incandescent lamps. If necessary, this part of the body can be used to increase the buoyancy of the probe, which is achieved by covering its end with a light transparent plug made, for example, of plexiglass.

 The remote control consists of a starting device 1, an electronic unit including a receiving transducer 2, a first amplifier 3, a differentiating cascade 4, a second amplifier 5, a pulse shaper 6, a counting and analyzing device 7, and a digital indicator 8, as well as a power supply unit (in Fig. 3 not shown).

 Starting device 1 (PP) is a board with a built-in socket for launching a probe (ZI) and an electronic unit and a power supply attached to it. The socket is made in the form of a cylindrical guide pipe having an inner diameter slightly larger than the diameter of the middle part of the probe. On the side surface of the nozzle there is a “Start” microswitch, the button of which is brought out through an opening in the nozzle wall to the inner surface of the latter. The "Start" microswitch is connected in series with the TV toggle switch ("on") in the electrical control circuit of the device.

Анодный ток ФЭУ, обусловленный световым потоком φ_п, т. е. рабочий ток при световой анодной чувствительности S_A= a/лм (ФЭУ-60) составит
I_A= S_A•φ_п= 15•10^-8a.
Отношение рабочего анодного тока I_А к темновому I_т=2•10^-8а (ФЭУ-60), т. е. отношение сигнал/шум равно I_А/I_т= 7,5, что вполне достаточно для нормальной работы устройства. При наличии в резервуаре оптически прозрачной жидкости максимальная глубина зондирования может быть меньше приведенной выше оценки. Она будет зависеть от величины коэффициента пропускания (прозрачности) жидкости и от высоты ее столба h.The receiving transducer 2 is made of standard elements and is a sensor emitted by the probe radiation. When used for coupling electromagnetic waves in the optical part of the spectrum, it can be a photoelectron multiplier (PMT), a photodiode, etc. converters. If the light flux emitted by the probe is φ _and = 0.5 lm, which is true when using standard miniature incandescent lamps, then the photomultiplier photomultiplier having a radius r _k = 5 • 10 _-3 m (PMT-60), with a distance to the probe L = 25 m will flow

The anode current of the PMT, due to the luminous flux φ _p , i.e., the working current at the light anode sensitivity S _A = a / lm (PMT-60) will be
I _A = S _A • φ _n = 15 • 10 ^-8 a.
The ratio of the working anode current I _A to the dark I _t = 2 • 10 ^-8 a (PMT-60), that is, the signal-to-noise ratio is I _A / I _t = 7.5, which is quite enough for the normal operation of the device. If there is an optically transparent liquid in the tank, the maximum sounding depth may be less than the above estimate. It will depend on the value of the transmittance (transparency) of the liquid and on the height of its column h.

 The first 3 and second 5 amplifiers are semiconductor DC amplifiers with a large input impedance, for example, operational amplifiers. Structurally, they can be implemented using chips.

 The differentiating cascade 4 is a passive four-terminal device and consists of a capacitance and resistance, connected in such a way that the voltage at its output is equal to the time derivative of the input voltage.

 The pulse shaper 6 consists of a reference frequency generator connected in a certain pattern, as well as standard logic and switching elements. It is implemented in conjunction with a counting and analyzing device 7 (ACS) in one microprocessor.

 Digital indicator 8 (IN) is the output stage of the electronic unit and is made of small-sized liquid crystal elements.

 The device operates as follows.

After unlocking the clamp, the clamp (starter) releases the probe and it falls out of the socket into the reservoir. At the same time, the “Start” microswitch button, previously pressed by the probe body, is also released. A normally closed contact of the microswitch through the included TV toggle switch closes the control circuit of the device and after a while τ _o all its elements are prepared for work: previously registered signals are accidentally deleted and "zeros" are set on all digital elements. When the probe reaches the phase boundary, the intensity of the radiation emitted by it rapidly changes, which causes corresponding changes in the output values of the receiving transducer (Fig. 1, B). Having passed amplifier 3, differentiating stage 4 and second amplifier 5, the signal is converted into a sequence of bell-shaped pulses of different polarity, similar to those shown in FIG. 1, B. Further, these pulses are standardized in the shaper 6 and used in the calculating-analyzing device 7 to determine the time intervals Τ _Σ and T _Σ1 and select the appropriate computational procedure. Depending on the number of detected pulses, the counting and analyzing device performs calculations according to formulas (1) (5) using well-known algorithms. The results (values X, h, L) are transmitted in a certain sequence to digital indicator 8.

Claims (3)

1. A method for determining the depth of tanks and the level of liquids, including launching (dropping) the probe in the direction of the bottom or the boundary surface of the fluid, emitting signals using a probe, receiving and processing these signals, and determining the desired values from the results of processing the received signals, characterized in that when probing, an autonomous disposable probe is used, which has variable buoyancy and the energy reserve necessary for signal emission, the moment of the probe’s start and the moments of change are recorded s radiation parameter associated with the probe reaching the tank bottom or the surface of the liquid and the tank bottom, measured intervals of time spent for the fall and the immersion of the probe and the passage of radiation in the medium, and the desired depth and the level calculated according to the number of parameter changes in the radiation from the formulas
L x
when changing the radiation parameter once (tank without liquid),
L x + h
when changing the radiation parameter three times (reservoir with liquid),

for v _n >> v

at v _n ≈ v

where L is the depth of the tank;
x fluid level or bottom mark of an empty tank, measured from the starting point of the probe;
h the height of the liquid column in the tank;
m is the mass of the probe;
m _o = βvρ _o added mass;
α empirical coefficient taking into account the aerodynamic and hydrodynamic qualities of the probe and the properties of the medium;
b is a numerical coefficient depending on the geometric shape of the probe;
V probe volume;
r _{o the} density of the medium in which the probe moves;
ρ is the average density of the probe substance;
v the speed of the probe;
v _n the propagation velocity of radiation in the medium;
q acceleration of gravity;
T, T ₁ const the time of change of the registered radiation parameter when the probe reaches the gas / liquid, gas / solid (T) or liquid / solid (T ₁ ) interfaces;
T _Σ = t _n1 -t _o ,
t ₀ probe start time;
t _n1 moment of registration of the first change in the radiation parameter, indicating that the probe has reached the liquid level or the bottom of an empty tank;
T _Σ1 = t _n3 -t _n2
t _n2 moment of registration of the second change in the radiation parameter, signaling the beginning of immersion of the probe in the liquid;
t _n3 moment of registration of the third change in the radiation parameter, signaling that the probe reaches the bottom of the reservoir with the liquid.  2. A device for determining the depth of tanks and the level of liquids, containing a probe and a control panel and signal processing, comprising a power supply unit, a receiving transducer, a first amplifier, a second amplifier, a pulse shaper, a counting and analyzing device and a digital indicator, characterized in that the probe is made in the form of a self-contained single-use radiation source having variable buoyancy and energy reserve for signal emission, has a starting device and ballast capacity with about apertures, and the control and signal processing panel is a passive part of the device, made using microelectronics, has low power consumption and additionally contains a starting device and a differentiating cascade connected in series between the first and second amplifiers.  3. The device according to claim 2, characterized in that the probe is made in the form of a rotation elongated along the body axis with a density and diameter varying in the longitudinal direction, has an arrangement of the centers of gravity of the mass and volume, ensuring stability of its axis orientation along the direction of gravity when located the probe in a homogeneous homogeneous environment and the loss of this stability at the phase boundary, the probe body is made of elastic material and is open from one end, the ballast tank is installed on the other end of the body, element The power supply is inserted with an interference fit into the housing and is connected with the help of a conductor and an insulated base contact to the made optical emitting transducer, the active part of which is recessed into the housing and facing its open end, and the starting device is made in the form of a spring clamp with a clamp put on the housing and compressing it at the point of contact of the battery and the emitting transducer, due to which the latter are disconnected.

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