SU1206665A1 - Method of determining rate of light phase formation on surface of steam-gas-liquid systems - Google Patents

Abstract

The invention relates to the investigation of light-phase (LF) separation processes in vapor-gas-liquid systems and can be used in chemical industry, flotation and thermal power engineering for calculating and designing heat and mass transfer processes. The purpose of the invention is to expand the range of detectable velocities and increase the reliability of their determination at a higher density of LF formation centers. A sealed vessel is supplied with the test liquid and LF vapor or gas. Oolna and snl shokasti

Description

The test liquid is filled with LF or heated to supersaturation, after which the liquid under study is overheated or overheated. The controlled area of the surface is illuminated perpendicularly to the direction of the emerging puff of LF. The average length of the ensemble of bubbles 6 is determined from the photograph and the total number of etched puffs of LF n is calculated. The linear dimensions of the illuminated layer of liquid t should satisfy the condition where s is the average diameter of the recorded bubble, ah is the minimum

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The invention relates to the investigation of light-phase (LF) separation processes in vapor-gas-liquid systems and can be used in chemical industry, flotation and thermal power engineering for calculating and designing heat and mass transfer processes.

The purpose of the invention is to expand the range of detectable velocities and to ensure the reliability of their determination at a higher density of the centers of formation of the light phase.

The drawing shows a scheme for implementing the method.

The diagram shows a valve 1, a smooth-walled vessel 2, a liquid 3, a thermometer 4, a controlled surface area 5, floating surfaces of LF 6, a lighting device 7, an illuminated layer of liquid 8, vapor or gas (LF) 9, a camera 10, an actuator 11 movement of the controlled area, valve 12 supply and discharge of LF, throttle device 13, pressure gauge 14, sensor 15 for measuring the velocity of movement.

The sealed liquid 3 is fed to the sealed smooth vessel 2 through valve 1 and the LF 9 vapor or gas is fed through valve 12. The liquid 3 is saturated with LF 9 or heated until it is overpaired, and then the liquid 12 is overheated or oversaturated with valve 12 3. Controlling 206665

the distance between the bubbles in the direction of the surface, at which they are distinguishable in the photo. The speed of movement of the monitored part of the surface V must satisfy the condition where f is the frequency of bubble separation, and b is the length of the monitored part in the direction of its movement. The rate of formation of the LF v / is determined.

hV is the formula where

T- is the density of the centers of LF formation, F is the area of the controlled site, silt.

The surface area 5 is evenly moved in a plane perpendicular to the direction of bubbling of the bubbles, by means of the actuator 11, and the speed of movement is measured by means of the sensor 15. Light up a thin layer of LSHDK. 8 and the camera 10, the optical axis of the lens. which is parallel to the direction of the emerging bubbles, the LF 6 particles falling into the illuminated layer 8 are recorded. The temperature and pressure of the test liquid are measured with a thermometer

4 and a pressure gauge 14. From the photograph, the average length f of the ensemble of puffs is determined by comparing with the simultaneously recorded length standard and the total number of

And captured puzfkov LF.

To register a discrete set of LF bubbles, the linear dimensions t of the illuminated fluid layer 8. must satisfy the condition d 6t 4 h

where d is the average diameter of the bubble to be detected, and K is the minimum distance between puffs in the direction of emergence, at which they are distinguishable in the photograph. In order to increase the resolution at a high density of LF centers of formation, a uniform movement of the surface to be tested is carried out at a speed V satisfying the condition V f6, where t is the bubble separation frequency, and 6 is the length

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controlled area in the direction of movement, which ensures the fixation of a discrete ensemble of bubbles that successively fall into the illuminated layer of liquid. The exposure time t at photographing is set equal to t / y, where experimentally is selected to obtain a discrete ensemble of bubbles in the photograph.

The bubble separation rate is defined as 4- -, the area of the test section F is estimated as, where a and b are the width and length of the test section. The rate W of LF formation, corresponding to the product of the density T. of the centers of LF formation, by the frequency of bubble separation, is determined by the formula

w ..-- a

An example. Air-saturated kerosene brand T-1 at a pressure of 0.2 MPa and a temperature of 300 K is placed in a cylindrical vessel made of plexiglass. The controlled surface area of 0,, 002 0.3 "10 m is fixed on a lever with a length of 0.063 m, rotating at a speed of 0.8 rev / sec. The speed of movement of the controlled area corresponds to 2f-0.0630.8 0.0504 ms (at, 002 m and the expected frequency of bubble breakage with the minimum required speed of movement should be 0.02). With an average diameter of the bubble, 2 mm and. the minimum distance for difference of pop-up bubbles is h-35 mm. The thickness of the illuminated layer is chosen to be 5.0 mm. The total number of bubbles in the ensemble .I 934. As an internal standard of length, use the image of the beam on the transparent wall of the container (L 4 cm). The average length of the ensemble of bubbles E in accordance with the standard used is 5 cm. Thus, the magnitude of the speedy

Editor A. Shishkin

Compiled by T.Titova Tehred O.Netse

Order 8702/44 Circulation: Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5

Branch PPP Patent, city Project 4

206665,

Formation of LF on the surface of this system is 3138 s-cm, which is 40 times more than the high density of LF formation centers compared with J in a known manner.

Claims (1)

Invention Formula 0 five 0 five five 0 five The method for determining the rate of formation of a light phase on the surface of vapor-gas-liquid systems, which means that in a closed volume at certain pressures and temperatures overheat or oversatuish the liquid of the system under test, illuminate the controlled surface area perpendicular to the direction of the floating of the light phase bubble. and area F, record the number of bubble bubbles in the illuminated H layer and determine the desired value, characterized in that, in order to broaden the range the zone of detectable velocities and ensuring the reliability of their determination at a higher density of the centers of formation of the light phase, the illumination of the fuel produced by a thin beam, whose linear dimensions t satisfy the condition where d is the average diameter of the powder recorded and h is the minimum distance between the bubbles in the direction of their emergence, in which they register in the entire discrete ensemble, the controlled surface area is moved in a plane perpendicular to the direction of the emergence of bubbles with a velocity V fb. where f is the frequency of separation of the bubbles, and is the length of the controlled area in the direction of its movement, measure the speed of movement V, estimate the average length of the ensemble of emerging bubbles t and determine the desired value w-Z f Proofreader L. Pilipenko