Device for measuring thickness of surface liquid film

Abstract

The utility model relates to the field of liquid film thickness measurement, and discloses a device for measuring the thickness of a surface liquid film, which comprises an annular fixer, an annular rotator, an annular guide rail and an annular gear, the rotating motor drives the annular rotator to rotate in the circumferential direction through the annular gear. The electric horizontal guide rail is fixed to the annular rotator and drives the sliding block to move axially, the stepping motor and the probe are arranged on the sliding block, and the stepping motor drives the probe to advance and retreat in the radial direction. The probe, a power supply, an ampere meter and a circuit switch form a detection loop, the rotating motor, the stepping motor and the electric horizontal guide rail are connected with a computer through data lines for control, and circumferential-axial multi-point liquid film thickness measurement is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of liquid film thickness measurement, and particularly relates to a measuring device for measuring surface liquid film thickness. BACKGROUND

[0002] Water is the source of life, the most important natural resource on earth, and the basis for human and other life to survive. At present, China is facing the serious problem of insufficient clean water resources, and sewage desalination treatment is of great significance to solve the lack of water resources. Existing sewage desalination technologies include distillation, reverse osmosis, electrolysis and ion exchange. Among them, low-temperature multi-effect evaporation is widely used due to its low water quality requirement and simple operation. Liquid film thickness is one of the key factors affecting the heat exchange efficiency of low-temperature multi-effect evaporation heat exchanger. Thin liquid film can reduce the thermal resistance in the falling film evaporation process, thereby increasing the heat exchange efficiency; thick liquid film can improve the stability of the film, so that the liquid film is not easy to break or fail, thereby improving the separation efficiency and evaporation efficiency. Existing liquid film measurement methods include laser method, ultrasonic method and spectral confocal instrument method, etc. These methods have the problems of high cost and difficult operation in the measurement of liquid film thickness in the falling film evaporator. In order to study the influence of liquid film thickness on the heat exchange efficiency of low-temperature multi-effect evaporator in the falling film evaporation process. Therefore, a measuring device is needed, which is low in cost, simple in operation, high in automation and can quickly and accurately measure the surface liquid film thickness of the heat exchange pipe at different positions in the falling film evaporation process. SUMMARY

[0003] In view of the deficiencies in the prior art, the utility model provides a device for measuring surface liquid film thickness.

[0004] To achieve the above-mentioned purpose, the utility model adopts the technical scheme that:

[0005] The probe is combined with the stepping motor to realize accurate measurement of the liquid film thickness by controlling the movement of the probe through electrical signals. This method uses the closed circuit formed by the contact of the probe with the liquid film and the metal pipe wall to reflect the change of the contact state of the probe with the liquid film through the change of the current. In the measurement process, the probe is initially in direct contact with the pipe wall, at which time the current meter reading is maximum; as the stepping motor drives the probe to gradually move away from the pipe wall, the circuit resistance gradually increases due to the existence of the liquid film, and the current gradually decreases. When the probe completely separates from the liquid film, the circuit is disconnected, and the current drops to zero. At this time, the total movement distance of the stepping motor is recorded, which is the thickness of the liquid film.

[0006] The utility model provides a device for measuring surface liquid film thickness. The device comprises;

[0007] Ring-shaped fixer 1, threaded hole 2, test tube avoidance hole 3, rotary motor 4, rotary motor fixer 5, ring-shaped rotator 6, ring-shaped guide rail 7, slide rail stabilizer 8, ring-shaped gear 9, electric horizontal guide rail 10, electric horizontal guide rail fixer 11, stepping motor fixer 12, probe avoidance hole 13, stepping motor 14, probe 15, bearing 16, wire 17, power supply 18, ammeter 19, switch 20, data line 21, computer 22, test tube 23, sliding block 24, bolt 25.

[0008] The ring-shaped fixer 1 is provided with a threaded hole 2, the test tube 23 is led out from the test tube avoidance hole 3, and the bolt 25 is connected with the threaded hole 2 and fixes the test tube 23 with the ring-shaped fixer 1; the ring-shaped fixer 1 and the rotary motor fixer 5 are provided with screw holes, the rotary motor fixer 5 is connected with the ring-shaped fixer 1 through the bolt 25 and fixes the rotary motor 4 with the ring-shaped fixer 1.

[0009] Further, the slide rail stabilizer 8 is connected with the ring-shaped guide rail 7 through a pulley, the slide rail stabilizer 8 can slide on the ring-shaped guide rail 7; the ring-shaped guide rail 7 and the ring-shaped gear 9 are provided with screw holes, the ring-shaped guide rail 7 is connected with the ring-shaped gear 9 through the bolt 25, the ring-shaped rotator 6 is provided with a groove, the ring-shaped rotator 6 groove and the ring-shaped gear 9 are both provided with screw holes, and the ring-shaped rotator 6 is connected with the ring-shaped gear 9 through the bolt 25.

[0010] Further, the ring-shaped rotator 6 is connected with the ring-shaped fixer 1 through the bearing 16; the shaft rod of the rotary motor 4 is in transmission connection with the ring-shaped gear 9, and the rotary motor 4 drives the ring-shaped rotator 6 to rotate.

[0011] Further, the electric horizontal guide rail fixer 11 is connected with the ring-shaped rotator 6 through the bolt 25 and fixes the electric horizontal guide rail 10 with the ring-shaped rotator 6; the electric horizontal guide rail 10 is provided with the sliding block 24, the sliding block 24 and the stepping motor fixer 12 are both provided with threaded holes, the stepping motor fixer 12 is connected with the sliding block 24 through the bolt 25 and fixes the stepping motor 14 with the sliding block 24, and the stepping motor 14 is led out through the probe avoidance hole 13.

[0012] Further, the probe 15 and the test tube 23 are respectively connected with the positive and negative poles of the power supply 18 through the wire 17, and the wire 17 is provided with the ammeter 19 and the circuit switch 20; the stepping motor 14, the rotary motor 4 and the electric horizontal guide rail 10 are connected with the computer 22 through the data line 21.

[0013] Compared with the prior art, the present application has the following advantages.

[0014] 1. A device for measuring the thickness of a surface liquid film, the method introduces a stepper motor, which is combined with a probe, and the position of the probe is accurately controlled by an electrical signal, so that the measurement of the liquid film thickness is more stable and accurate. At the same time, the structure is simple and convenient to change, and the device structure can be changed according to the engineering requirements, and different specifications and precision stepper motors can be replaced according to the engineering requirements and the range of liquid film thickness.

[0015] 2. A device for measuring the thickness of a surface liquid film, the design of the measuring device structure enables it to measure the liquid film thickness at different circumferential angles and axial positions of the pipe, so as to comprehensively grasp the liquid film thickness distribution and improve the comprehensiveness of the measurement. The circumferential and axial movement of the probe is driven by a computer-controlled motor, which makes the device not only highly automated, but also more accurate and convenient to control in three-dimensional movement of the probe.

[0016] 3. A device for measuring the thickness of a surface liquid film, the measuring device is low in cost, stable and reliable compared with the traditional measuring device, and has high automation degree, and is more suitable for precise measurement of the thickness of the surface liquid film in industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The utility model relates to a kind of measuring device for measuring the thickness of surface liquid film structure schematic view.

[0018] Figure 2 For Figure 1 The structure schematic view of middle annular gear and annular guide rail DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the utility model will be clearly and completely described below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0020] In the description of the utility model, it needs to be explained that the terms "top", "bottom", "one side", "the other side", "front", "back", "middle part", "inside", "top end", "bottom end" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application; the terms "first", "second" and "third" are only for the purpose of description, and cannot be understood as indicating or implying relative importance; in addition, unless otherwise explicitly specified and limited, the terms "mounting", "connection" and "connection" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For ordinary skilled persons in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0021] As Figure 1 It is a device for measuring the thickness of a surface liquid film, which comprises a ring-shaped fixing device 1, a threaded hole 2, a test tube avoiding hole 3, a rotating motor 4, a rotating motor fixing device 5, a ring-shaped rotating device 6, a ring-shaped guide rail 7, a sliding rail stabilizer 8, a ring-shaped gear 9, an electric horizontal guide rail 10, an electric horizontal guide rail fixing device 11, a stepping motor fixing device 12, a probe avoiding hole 13, a stepping motor 14, a probe 15, a bearing 16, a wire 17, a power supply 18, an ammeter 19, a switch 20, a data line 21, a computer 22, a test tube 23, a sliding block 24 and a bolt 25.

[0022] Specifically, the liquid film thickness measuring device of the present application comprises a ring-shaped fixing device 1 at the left and right ends, the outer shape of the ring-shaped fixing device 1 is circular, and a test tube avoiding hole 3 is arranged in the center part for passing through test tubes of different diameters. The surface of the ring-shaped fixing device 1 is provided with three uniformly distributed threaded holes 2 for mounting the bolts 25. These bolts 25 pass through the threaded holes 2 into the test tube avoiding hole 3 and directly press the test tube 23, so as to realize the fixation of the test tube 23. This design makes the device adapt to test tubes 23 of different outer diameters, and has higher universality and flexibility. The cross section of the ring-shaped fixing device 1 is designed with a threaded hole, and the threaded hole is used to connect and fix the rotating motor 4 and the rotating motor fixing device 5 on the ring-shaped fixing device 1 through the bolts 25.

[0023] The annular rotator 6 is provided with a groove, and the groove surface is provided with a plurality of threaded holes. The annular gear 9 is provided with threaded holes, and the annular gear 9 is connected and fixed with the annular rotator 6 through the bolts 25, and at the same time, the bolts 25 also fix the annular guide rail 7 on the annular gear 9. The tangent surface of the annular rotator 6 is designed with threaded holes, and the threaded holes connect and fix the electric horizontal guide rail 10 and the electric horizontal guide rail fixer 11 on the annular rotator 6 through the bolts 25. The electric horizontal guide rail 10 is provided with a sliding block 24, and the sliding block 24 is provided with a plurality of threaded holes, which are used to install the stepping motor fixer 12, so as to connect the stepping motor 14 with the sliding block. The stepping motor fixer 12 is provided with a probe avoiding hole 13 in the center position, and the design purpose of the hole is to allow the probe 15 to pass through. The sliding block 24 can be driven by the electric horizontal guide rail 10 according to the requirement, and drives the probe 15 to move along the axial direction of the test tube 23, so that the device can flexibly measure the liquid film thickness of different positions of the test tube 23.

[0024] The annular rotator 6 is provided with a groove, and the groove surface is provided with a plurality of threaded holes. The annular gear 9 is provided with threaded holes, and the annular gear 9 is connected and fixed with the annular rotator 6 through the bolts 25, and at the same time, the bolts 25 also fix the annular guide rail 7 on the annular gear 9. The tangent surface of the annular rotator 6 is designed with threaded holes, and the threaded holes connect and fix the electric horizontal guide rail 10 and the electric horizontal guide rail fixer 11 on the annular rotator 6 through the bolts 25. The electric horizontal guide rail 10 is provided with a sliding block 24, and the sliding block 24 is provided with a plurality of threaded holes, which are used to install the stepping motor fixer 12, so as to connect the stepping motor 14 with the sliding block. The stepping motor fixer 12 is provided with a probe avoiding hole 13 in the center position, and the design purpose of the hole is to allow the probe 15 to pass through. The sliding block 24 can be driven by the electric horizontal guide rail 10 according to the requirement, and drives the probe 15 to move along the axial direction of the test tube 23, so that the device can flexibly measure the liquid film thickness of different positions of the test tube 23.

[0025] The probe 15 and the test tube 23 are connected with the positive and negative electrodes of the power supply 18 through the wires 17, and the wires 17 are provided with the ammeter 19 and the circuit switch 20. The stepping motor 14, the rotating motor 4 and the electric horizontal guide rail 10 are connected with the computer 22 through the data line 21.

[0026] The measuring process of the liquid film thickness measuring device of the present application is as follows: first, install the annular holder 1 on the test tube 23, make the test tube 23 pass through the test tube avoiding hole 3, and fix the test tube 23 on the annular holder 1 by the bolt 25. While tightening the bolt 25, adjust the tightening degree of the bolt 25 to ensure that the annular holder 1 is firmly connected with the test tube 23 to avoid displacement or shaking of the test tube in the subsequent measuring process. Then, align and fix the rotating motor holder 5 on the threaded hole of the annular holder 1 by the bolt 25, and install the rotating motor 4 on the rotating motor holder 5. Connect the annular rotator 6 with the bearing in the annular holder 1 through the shaft to ensure the smooth rotation of the rotator. Then pass the shaft of the rotating motor through the through hole of the slide rail stabilizer 8 and connect it with the annular gear 9. Connect the slide rail stabilizer 8 with the annular guide rail 7 through the pulley to ensure the stability and accuracy of the rotating motor during operation. The cross section of the annular rotator 6 is designed with threaded holes, and the electric horizontal guide rail 10 and the electric horizontal guide rail holder 11 are installed on the annular rotator 6 by the bolt 25 to form the horizontal movement structure of the probe.

[0027] The slide block 24 is designed with several threaded holes for installing the stepping motor holder 12 to fix the stepping motor 14 with the slide block 24. The center part of the stepping motor holder 12 is provided with a probe avoiding hole 13 to ensure that the output shaft of the stepping motor can freely extend through the probe avoiding hole 13 and drive the probe 15 to move in the vertical direction.

[0028] Connect the probe 15 with the positive and negative electrodes of the power supply 18 through the wires 17, and connect the ammeter 19 and the circuit switch 20 in the circuit to monitor the current change when the probe contacts with the liquid film. Connect the rotating motor 4, the electric horizontal guide rail 10 and the stepping motor 14 with the computer 22 through the data line 21. Start the control program on the computer to initialize the device:

[0029] The rotating motor 4 drives the annular rotator 6 to reset to the initial position to ensure that the probe is at the specified starting position of the test tube 23. The electric horizontal guide rail 10 drives the slide block 24 to move to the starting position of the horizontal guide rail to ensure that the initial position of the probe is consistent with the axial direction of the test tube. The stepping motor 14 adjusts the probe 15 to a position away from the surface of the test tube 23 to ensure the initial accuracy of the vertical measurement process.

[0030] The computer control program is started, and the stepper motor 14 is driven to gradually approach the wall of the test tube 23 by the probe 15. When the probe 15 contacts the wall of the test tube 23, the circuit is turned on, and the current reaches the maximum value, which is used to calibrate the initial contact position of the probe 15. The stepper motor 14 is controlled by the computer 22 to drive the probe 15 to gradually move away from the tube wall at a set step. During this process, due to the existence of the liquid film, the resistance between the probe 15 and the tube wall of the test tube 23 gradually increases, and the reading of the ammeter 19 gradually decreases. When the probe 15 moves to a certain distance, the reading of the ammeter 19 suddenly drops to zero, indicating that the probe 15 is completely separated from the liquid film, and the circuit is turned off. At this time, the computer 22 records the movement distance of the stepper motor 14, which is the thickness value of the liquid film.

Claims

1. A device for measuring the thickness of a surface liquid film, comprising a ring-shaped holder (1), a threaded through-hole (2), a test tube avoidance hole (3), a rotary motor (4), a rotary motor holder (5), a ring-shaped rotator (6), a ring-shaped guide rail (7), a slide rail stabilizer (8), a ring-shaped gear (9), an electric horizontal guide rail (10), an electric horizontal guide rail holder (11), a stepping motor holder (12), a probe avoidance hole (13), a stepping motor (14), a probe (15), a bearing (16), a wire (17), a power supply (18), an ammeter (19), a switch (20), a data line (21), a computer (22), a test tube (23), a slide block (24), a bolt (25), characterized in that The annular fixer (1) is provided with a threaded hole (2), the test tube (23) is out of the test tube avoiding hole (3), the bolt (25) is connected with the threaded hole (2) and fixes the test tube (23) with the annular fixer (1); The annular fixer (1) and the rotary motor fixer (5) are provided with threaded holes, the rotary motor fixer (5) is connected with the annular fixer (1) by the bolt (25) and fixes the rotary motor (4) with the annular fixer (1); The slide rail stabilizer (8) is provided with two pairs of pulleys and through holes, the slide rail stabilizer (8) is connected with the annular guide rail (7) through the pulley, and the slide rail stabilizer (8) can slide on the annular guide rail (7); The annular guide rail (7) and the annular gear (9) are provided with screw holes, the annular guide rail (7) is connected with the annular gear (9) through the bolt (25), the annular rotator (6) is provided with a shaft and a groove, the annular rotator (6) groove and the annular gear (9) are provided with threaded holes, and the annular rotator (6) is connected with the annular gear (9) through the bolt (25); The annular fixer (1) is provided with a bearing hole, and the annular rotator (6) is connected with the annular fixer (1) through the bearing (16); The shaft of the rotary motor (4) is in transmission connection with the annular gear (9), and the rotary motor (4) drives the annular rotator (6) to rotate; The electric horizontal guide rail fixer (11) and the annular rotator (6) are provided with screw holes, the electric horizontal guide rail fixer (11) is connected with the annular rotator (6) through the bolt (25) and fixes the electric horizontal guide rail (10) with the annular rotator (6); The electric horizontal guide rail (10) is provided with a sliding block (24), the sliding block (24) and the stepping motor fixer (12) are provided with threaded holes, the stepping motor fixer (12) is connected with the sliding block (24) through the bolt (25) and fixes the stepping motor (14) with the sliding block (24), and the stepping motor (14) is out of the probe avoiding hole (13); The probe (15) and the test tube (23) are respectively connected with the positive and negative electrodes of the power supply (18) through the wire (17), and the wire (17) is provided with an ammeter (19) and a circuit switch (20); The stepping motor (14), the rotary motor (4) and the electric horizontal guide rail (10) are connected with the computer (22) through the data line (21).

2. The apparatus for measuring the thickness of a surface liquid film according to claim 1, wherein The rotary motor (4) drives the annular rotator (6) to rotate in the circumferential direction, adjusts the circumferential position of the electric horizontal guide rail (10) and the probe (15).

3. The apparatus for measuring the thickness of a surface liquid film according to claim 1, wherein The slide rail stabilizer (8) is provided with a through hole, the through hole is used for letting the shaft of the rotary motor (4) pass through, so as to stabilize the rotary motor (4) and limit the swing thereof.

4. The apparatus for measuring the thickness of a surface liquid film according to claim 1, wherein The electric horizontal guide rail (10) is provided with a sliding block (24), the stepping motor fixer (12) is driven to move in the horizontal direction through the sliding block (24), so as to realize the measurement of the probe (15) at different horizontal positions.

Images