CN111413163A

CN111413163A - Laminar flame soot collecting and sampling device and sampling method

Info

Publication number: CN111413163A
Application number: CN202010278091.0A
Authority: CN
Inventors: 楚化强; 胡家龙; 聂晓康; 牙宇晨; 周勇
Original assignee: Anhui University of Technology AHUT
Current assignee: Anhui University of Technology AHUT
Priority date: 2020-04-10
Filing date: 2020-04-10
Publication date: 2020-07-14

Abstract

The invention discloses a laminar flame soot collection and sampling device and a laminar flame soot collection and sampling method, and belongs to the technical field of soot particle collection. This sampling device is collected to soot includes that capillary probe and filter membrane holder can be replaced in the sampling, the sampling can be replaced the capillary probe intermediate position and be equipped with the sampling hole, one end or both ends can be threaded simultaneously, can change according to different fuel and different combustors to solve different fuel soot pollution and sampling device and the improper problem of combustor, can fix on the test bench, also can tear down the base and keep flat the accurate regulation of realizing going forward back and forth from top to bottom on the optical platform, it is troublesome or unable to change to have solved traditional sampling device capillary probe effectively, with the combustor improper adaptation, adjust inconvenient and inaccurate problem.

Description

Laminar flame soot collecting and sampling device and sampling method

Technical Field

The invention relates to the technical field of soot particle collection, in particular to a laminar flame soot collection and sampling device and a laminar flame soot collection and sampling method.

Background

Since combustion of substances is a very complex process, research on the combustion characteristics of fuels has been the leading edge of many fields. In the combustion process, besides light and heat, some harmful substances are also generated, which causes environmental pollution. The fuel is not fully combusted to generate soot which can harm the environment and human health, reduce the combustion efficiency of combustion equipment, influence the radiation heat transfer characteristic of flame, and influence the atmospheric quality when the soot enters the atmosphere, for example, London smoke is caused by industrial wantonly vicious unregulated and uncontrolled development. Researches on a forming mechanism and an emission reduction method of nitrogen oxides in fuel combustion have been made little, but the explanation of soot emission still has a lot of ambiguity, which is mainly because the physical change and the chemical reaction generated by soot in flame are complex, and the variability of the aggregate characteristics of soot in different flame laminar flows (such as particle size, particle density, aggregate structure, soot volume fraction and the like) is large, so that effective detection data is difficult to obtain. Therefore, the method has great practical significance for analyzing and processing the soot, and representing the quality of the soot by observing the crystallization degree of the soot and the oxidation activity of the soot so as to realize energy conservation and emission reduction.

At present, the methods for internationally researching the generation and distribution rule of soot in flame mainly comprise a contact method and a non-contact method.

1) The non-contact method is mainly an optical method, which comprises detection by using a laser technology and detection by using a flame-based emission spectrum technology, wherein the optical method can obtain a detection result with time and space resolution capability and does not interfere a detected object, for example, CN201610811876.3 discloses a carbon black detection system and a detection method in laminar flame of hydrocarbon fuel. However, the non-contact method cannot observe information such as soot morphology and structure, and soot particles are divided into two states of particle precursors and nucleation particles, and the particle precursors do not absorb visible light, which is generally ignored by the optical method to cause inaccuracy of results.

2) Most of researches on laminar flame soot collection adopt a traditional contact collection method, and the contact collection has the advantages of intuition and reliable experimental conclusion, for example, CN201810547516.6 discloses a system for collecting soot in laminar flame of hydrocarbon fuel and a particle size analysis method, and a transmission electron microscope is used for representing the morphology structure of soot particles; the particle size of basic particles of the carbon smoke is counted by means of NanoMeasurer particle size analysis software, and then nonlinear fitting is carried out on particle diameter distribution. However, the influence on the flame due to the contact with the flame cannot be avoided, so that the experimental result has deviation, sampling devices in the market have various advantages and disadvantages, the precision is high, the price is high, the popularization is difficult to realize, and the sampling devices cannot be used by all researchers; or the accuracy is low, which causes adverse effect on the subsequent soot treatment, and influences the analysis of the experiment and misleading the conclusion. Meanwhile, the traditional experiment device can only be used for one or one type of experiment table, the capillary probe fixing mode is more traditional, the device cannot be detached or is troublesome to detach, the adjustment of sampling of different heights of flame is not accurate, the whole process is very complex and time-consuming, and the precision is difficult to guarantee.

Aiming at laminar flame soot collection, the device usually comprises a test bed and a soot collection device, wherein the test bed mainly comprises a laminar flame burner, so that three important problems are faced in the experimental process, namely how a sampling device does not influence a sampling object or reduces the influence to the greatest extent; secondly, how to accurately adjust the sampling at different heights by the sampling device; and thirdly, how to avoid the influence of the combustion products of the fuel in the previous experiment on the current experiment result when different fuels are used. In the patent of invention of CN201710984620.7, a monochromatic laser is used to induce an incandescent light nanometer-level soot particle size measuring device, although non-contact detection is ensured, it cannot observe information such as soot morphology and structure, and the soot particles are divided into two states of particle precursor and nucleation particles, and the particle precursor does not absorb visible light; in the patent of CN201811128367.6 invention, the contact type is adopted to collect soot, and the influence of gas dilution and external airflow on the research of flame are combined, but the accurate adjustment of sampling at different heights cannot be realized, and the adjustment is too complicated, time-consuming and labor-consuming each time; in the patent of CN201810390912.2 invention, the volume of the foam alloy double-layer particle filtering system is large, and it can only be determined macroscopically whether to reduce emission, and the filter has an absorption effect on pollutants such as soot, and the collected soot is difficult to be collected and analyzed for the second time, and is difficult to be applied to scientific research and analysis, so that the application scope is narrow.

Therefore, according to the above analysis, the soot collection and sampling device in the prior art has the problems that the sampling device has influence on the sampling object, the sampling device is difficult to realize accurate adjustment of sampling at different heights, and different fuels are adopted, so that the influence of the combustion products of the last experimental fuel on the current experimental result cannot be avoided.

Disclosure of Invention

1. Problems to be solved

Aiming at the technical problems, the invention provides the convenient laminar flow flame soot collection and sampling device which can accurately adjust the sampling height, conveniently replace the capillary probe and is suitable for different experiment racks.

Similarly, the invention also provides a method for collecting and sampling the soot of the laminar flow flame, and the steps are connected in order.

2. Technical scheme

In order to solve the problems, the technical scheme adopted by the invention is as follows:

the invention relates to a laminar flow flame soot collecting and sampling device, which comprises:

the adjusting and clamping unit comprises a clamp, a first adjuster, a second adjuster vertically and orthogonally arranged with the first adjuster and a third adjuster vertically and orthogonally arranged with the second adjuster, and the clamp is arranged on the upper side surface of the first adjuster;

the sampling unit comprises a hollow clamping seat, a capillary probe provided with a sampling hole is arranged on the clamping seat, and the clamping seat is fixed on the clamper;

the filter unit comprises a filter membrane holder, the filter membrane holder is provided with at least two filter membrane clamping sheets, the filter membrane clamping sheets are fixed through bolts, a boss is reserved on the surface of one filter membrane clamping sheet, a groove matched with the boss is reserved on the surface of the other corresponding filter membrane clamping sheet, through holes are formed in the boss and the groove, the boss and the groove are mutually attached, the air tightness of the whole filter unit is guaranteed, the filter membrane can be firmly fixed, a placing groove is formed in the boss, and a filter membrane is arranged in the placing groove;

the pressure analysis and adjustment unit comprises two pressure gauges which are arranged along the direction of the air flow and can be adjusted, the pressure gauges are fixedly connected and communicated with the filter membrane holder, the real-time pressures of two positions can be observed, the pressure can be adjusted, and the influence of overlarge pressure difference on the collected soot flame and the damage of experimental instruments are avoided;

the clamping seat, the capillary probe, the filter membrane clamp holder and the pressure gauge form a soot collection sampling channel, when the device is used, the pressure gauge on one side is connected with a vacuum pump through an adapter port and a hose, and the pressure gauge on the other side is connected with an inert gas tank through the adapter port and the hose, such as nitrogen, argon and the like.

In a possible embodiment of the present invention, the first adjuster, the second adjuster, and the third adjuster have the same structure, and the third adjuster includes a first adjusting disc and a second adjusting disc, the first adjusting disc is provided with a first guide slot and a mounting hole, the bottom of the first guide slot is provided with a rack sliding slot, the rack sliding slot is provided with a second transmission gear, the mounting hole is provided with an adjusting rod connected to the second transmission gear, and the adjusting rod drives the second transmission gear to rotate; the second adjusting disk is provided with a first sliding block, the first sliding block is provided with a second transmission rack, the first sliding block is embedded in the first guide groove, the first adjusting disk and the second adjusting disk are in meshing transmission with the second transmission gear through the second transmission rack, and horizontal adjustment of the second adjusting disk relative to the first adjusting disk is achieved.

In a possible embodiment of the present invention, a first scale is horizontally disposed on one side of the first adjusting plate, and a first indicating arrow is disposed on one side of the second adjusting plate.

In a possible embodiment of the present invention, the first adjusting disk is provided with an auxiliary guide groove, the second adjusting disk is correspondingly provided with an auxiliary guide slider, and the auxiliary guide slider is embedded in the auxiliary guide groove; the cross-sectional shapes of the first guide groove and the first sliding block are both dovetail shapes.

In a possible implementation manner of the invention, the capillary probe is a capillary stainless steel probe or a capillary quartz probe, and external threads with consistent turning directions are annularly arranged at two ends of the capillary stainless steel probe or the capillary quartz probe and are matched with an internal thread hole arranged on the clamping seat, so that one-time installation and synchronous matching of the internal threads of the clamping seat can be realized, and convenient installation is realized.

In a possible embodiment of the present invention, the internal thread hole of the clamping seat is provided with an external chamfer at the beginning; the external diameter of the external thread at the two ends of the capillary stainless steel probe or the capillary quartz probe is slightly smaller than the external diameter of the capillary stainless steel probe or the capillary quartz probe, and the external diameter of the external thread is tightly matched with the internal threads of the clamping seats at the two ends, so that the air tightness is ensured.

In a possible embodiment of the present invention, a protection pad is further disposed in the placement groove, and the protection pad corresponds to the filter membrane in size, and can well support the filter membrane to protect the filter membrane, so as to prevent the filter membrane from being damaged by the airflow pressure difference.

In a possible embodiment of the present invention, the adjusting and clamping unit further includes an adjuster base, and the third adjuster is disposed on the adjuster base and fixed by a bolt.

The invention also provides a sampling method of the laminar flame soot collecting and sampling device, which comprises the following specific steps:

s101, opening a carbon filter membrane holder of a filter unit, placing a filter membrane in a protection pad, sequentially arranging the filter membrane in the filter unit according to the flowing direction of inert atmosphere and in a mode that the filter membrane is arranged above and below a protection pad, adjusting bolts until bosses and grooves are in order correspondingly, and tightly attaching filter membrane holding pieces;

s102, placing an adjusting clamping unit on an optical platform, adjusting the distance of a clamping device to meet the length of a clamping seat, and then fixing the clamping device; adjusting the horizontal distance from the adjusting rod on the second adjuster to the clamping seat to be equal to the length of the selected sampling capillary probe, and adjusting the adjusting rod on the first adjuster to a preset height equal to the vertical position of the clamping seat in height, so as to realize the alignment and height adjustment of the clamping seat;

s103, taking out a clean sampling capillary probe, screwing the sampling capillary probe into the internal thread hole of the clamping seat, and firstly adjusting the adjusting rod until the sampling hole of the capillary probe faces downwards; then adjusting a second adjuster, and adjusting the sampling hole of the capillary probe to the horizontal position with the center of the flame of the burner;

step S104, sequentially connecting the filtering unit, the sampling unit and the pressure analysis and adjustment unit, wherein a pressure gauge on one side of the filtering unit is connected with a vacuum pump through an adapter port and a hose, and a pressure gauge on the other side of the filtering unit is connected with an inert gas tank through an adapter port and a hose;

s105, connecting a pipeline of the combustor, checking whether the gas pipeline leaks gas or not, opening an inert gas tank and a vacuum pump, and adjusting a pressure gauge to a preset pressure; introducing gas and oxidant gas, igniting the flame, adjusting a third adjuster to move the sampling capillary probe into the flame for soot collection;

and S106, adjusting the regulator to move the sampling capillary probe out of the flame after the soot is collected and the time is up, disassembling the lower filtering unit, and taking out the filter membrane to collect and concentrate for subsequent detection.

s102, fixing a regulator base on a test bench; adjusting the distance of the clamp holder to meet the length of the clamp seat, and then fixing the clamp holder; adjusting the horizontal distance from the adjusting rod on the second adjuster to the clamping seat to be equal to the length of the selected sampling capillary probe, and adjusting the adjusting rod on the first adjuster to a preset height equal to the vertical position of the clamping seat in height, so as to realize the alignment and height adjustment of the clamping seat;

3. Advantageous effects

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention can accurately adjust the sampling height, conveniently replace the capillary probe and is suitable for the convenient soot sampling test bed of different experiment racks, and the test bed comprises a sampling unit, a filtering unit, an adjusting and clamping unit, a pressure analyzing and adjusting unit and a switching port, wherein the sampling unit, the filtering unit, the adjusting and clamping unit and the pressure analyzing and adjusting unit are sequentially and alternately connected through the switching port, so that the continuity of functions is realized; in the invention, a gear meshing transmission mode is adopted, so that the sampling device can be randomly adjusted to a preset position up and down or back and forth under a certain condition, and the adjustment has continuity; the problem that the traditional sampling device cannot be continuously adjusted is solved, and the problems that the traditional sampling device needs to disassemble and assemble a large number of parts each time of adjustment, and is time-consuming and labor-consuming are solved;

(2) according to the invention, each adjusting disc is provided with a scale, the movable part is provided with a first indicating arrow, when the movable part is adjusted up and down or back and forth, the adjusting scale can be set, and the movable part is adjusted to the preset scale only by referring to the first scale, so that the adjustable scale can be accurately adjusted and is simple and rapid to operate; by arranging the first scale, the sampling device has higher adjustment precision, so that the preset sampling height is accurately determined, and later analysis and processing are facilitated;

(3) according to the invention, each first regulator and each second regulator are vertically fixed by an L-angle-shaped connecting piece, the second regulator and the third regulator are horizontally arranged below and mutually vertical, and one regulator is vertically arranged above, so that the vertical, left-right and front-back regulation of two capillary probe clamping seats can be realized by adopting the structure, the distance between the two capillary probe clamping seats and a sampling capillary probe (a capillary stainless steel probe or a capillary quartz probe) can be conveniently regulated to adapt to the dynamic regulation of different experiment tables, a set of experiment device is adapted to different combustors, and the comparison of carbon smoke analysis among different combustors is realized;

(4) according to the invention, the detachable moving platform base is arranged below the adjusting and clamping unit, the vertical groove capable of clamping the experiment table is arranged on the base, and the nut can be rotated according to the thickness of different experiment table frames to realize clamping, so that the adjustable moving platform base is suitable for different combustors and experiment tables; meanwhile, the movable base can be conveniently detached, the regulator base can be detached in a sampling experiment in which the sampling device can be placed on the optical platform, and the sampling device can be directly placed on the optical platform for the experiment;

(5) compared with the traditional sampling device, the sampling capillary probe (a capillary stainless steel probe or a capillary quartz probe) is thinner, and the outer diameter of a sampling area is 0.2-2 mm; in the process of sampling by a contact method, the influence of a sampling device on sampling flame should be avoided as much as possible, but the traditional sampling device has insufficient flexibility, so that in order to avoid the breakage or damage of a sampling capillary probe (a capillary stainless steel probe or a capillary quartz probe), the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) cannot be made finer, the influence on the sampling flame is larger, and the acquired soot has low contrast when being analyzed by XRD (X-ray diffraction), Raman, thermogravimetry and other detection results, and even has consistent soot analysis results at different heights; the sampling area of the sampling capillary probe (a capillary stainless steel probe or a capillary quartz probe) can be made very thin, so that compared with the traditional sampling device, the influence on sampling flame can be greatly reduced, and the accurate analysis of a detection analysis result is realized;

(6) according to the invention, the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) can be threaded at two ends, so that different sampling capillary probes (the capillary stainless steel probe or the capillary quartz probe) can be replaced according to requirements in the combustion sampling process of different fuels to avoid the influence of the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) at the last time on the current experimental result, and meanwhile, the sampling capillary probes (the capillary stainless steel probe or the capillary quartz probe) with different outer diameters can be selected according to requirements and precision, so that the defect of soot pollution caused by combustion of different fuels can be avoided;

(7) the integral rotation directions of the threads at the two ends of the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) are consistent, so that the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) can smoothly enter the capillary probe clamping seats at the two ends along the same rotation direction on the premise of not moving other experimental devices. The problem that the sampling capillary probe (a capillary stainless steel probe or a capillary quartz probe) and other auxiliary equipment are time-consuming and labor-consuming to adjust back and forth at the same time can be avoided, the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) and other auxiliary equipment are easily unsynchronized to adjust back and forth at the same time, and the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) is damaged or even destroyed;

(8) the tapered section with a certain angle is arranged at the inner tail end of the threads at the two ends of the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe), the tapered section corresponds to the tapered section at the outer end of the internal thread of the capillary probe holder, and when the threads at the two ends of the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) are completely screwed into the internal thread of the capillary probe holder, the tapered section on the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) is attached to the tapered section of the internal thread of the capillary probe holder, so that the problem of air leakage of the device in the sampling process can be solved, and the air tightness of the device is ensured;

(9) according to the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) provided by the invention, as the outer diameter of the sampling area is thinner, the aperture of a rotary hole can be smaller when the sampling hole is rotated, so that excessive soot (including liquid state soot, nucleation form soot, oxidized soot and the like) can enter in unit time when sampling is carried out, the entering soot is relatively isolated, the phenomenon of agglomeration and the like after leaving flame is avoided, and the original form and characteristics of the soot are better protected;

(10) the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) can realize that the capillary probe clamping seat is only screwed into one side of the sampling capillary probe (the capillary stainless steel probe or the capillary quartz probe) and is provided with the thinner capillary probe (the capillary stainless steel probe or the capillary quartz probe), so that the sampling capillary probe can be directly inserted into flame for sampling, and meanwhile, the influence on the flame is small;

(11) the filtering unit comprises a filtering membrane holder, and the filtering membrane holding piece is provided with a boss and a groove which are opposite, so that the filtering membrane holder can be combined more tightly during fitting, and the air tightness of the sampling device is strictly ensured;

(12) the filtering unit is provided with a protective pad arranged at the downstream of the inert atmosphere and supporting the sampling filtering membrane, so that the filtering membrane is prevented from being damaged or destroyed by the pressure difference between the upstream and the downstream of the inert atmosphere;

(13) the filtering unit is provided with the two filter membrane holders, so that the filtering effect is better compared with that of a traditional single-layer filter, more soot can be adsorbed to the sampling filter membrane, the sampling efficiency is improved, and the environmental pollution is reduced;

(14) the pressure analysis and adjustment unit consists of two pressure gauges with adjustable pressure arranged along the direction of the inert gas flow, can observe the real-time pressure of two positions, can adjust the pressure, and avoids the influence of overlarge pressure difference on the collected soot flame and the damage of an experimental instrument.

Drawings

The technical solutions of the present invention will be described in further detail below with reference to the accompanying drawings and examples, but it should be understood that these drawings are designed for illustrative purposes only and thus do not limit the scope of the present invention. Furthermore, unless otherwise indicated, the drawings are intended to be illustrative of the structural configurations described herein and are not necessarily drawn to scale.

FIG. 1 is a schematic structural diagram of a laminar flame soot collection and sampling device according to the present invention;

FIG. 2 is a schematic structural diagram of a sampling unit of the laminar flame soot collection and sampling device of the present invention;

FIG. 3 is an exploded view of a filter unit of the laminar flame soot collection and sampling device of the present invention;

FIG. 4 is a diagram of the filter membrane clamping piece and the protection pad of the laminar flame soot collection and sampling device of the present invention;

FIG. 5 is a schematic structural view of a graph adjustment clamping unit of the laminar flame soot collection and sampling device of the present invention;

FIG. 6 is an exploded view of a third regulator of the present invention;

FIG. 7 is an exploded view of an XRD capsule according to the present invention;

FIG. 8 is a diagram of the result of soot XRD detection collected by the present invention;

FIG. 9 is a diagram of the result of thermogravimetric detection of soot collected by the present invention.

The notation in the figure is:

1. the adjusting and clamping device comprises an adjusting and clamping unit, 11, a clamp, 12, a first adjuster, 13, a second adjuster, 14, a third adjuster, 141, a second adjusting disc, 1411, a first indicating arrow, 1412, an auxiliary guide slide block, 1413, a first slide block, 1414, a second transmission rack, 142, a first adjusting disc, 1421, an adjusting rod, 1422, a mounting hole, 1423, a second transmission gear, 1424, a first guide groove, 1425, a rack sliding groove, 1426, an auxiliary guide groove, 1427, a first scale, 15, an adjuster base and a 16, L angle-shaped connecting piece;

2. a sampling unit; 21. a clamping seat; 211. an internally threaded bore; 22. a capillary probe; 221. a sampling hole; 222. an external thread;

3. a filtration unit; 31. a filter membrane clamping sheet; 311. a boss; 312. a placement groove; 313. a groove; 32. a protection pad;

4. a pressure analysis adjustment unit; 41. a pressure gauge;

5. a transfer port;

6. an XRD detection vessel; 61. detecting a dish slide; 62. a slide groove; 63. and (5) covering with a glass slide.

Detailed Description

The following detailed description of exemplary embodiments of the invention refers to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration exemplary embodiments in which the invention may be practiced. Although these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be realized and that various changes to the invention may be made without departing from the spirit and scope of the present invention. The following more detailed description of the embodiments of the invention is not intended to limit the scope of the invention, as claimed, but is presented for purposes of illustration only and not limitation to describe the features and characteristics of the invention, to set forth the best mode of carrying out the invention, and to sufficiently enable one skilled in the art to practice the invention. Accordingly, the scope of the invention is to be limited only by the following claims.

The detailed description and exemplary embodiments of the invention will be better understood when read in conjunction with the appended drawings, where the elements and features of the invention are identified by reference numerals.

Example 1

As shown in fig. 1, the laminar flow flame soot collection and sampling device of the present invention comprises an adjustment clamping unit 1, a sampling unit 2, a filtering unit 3, and a pressure analysis adjusting unit 4, wherein the pressure analysis adjusting unit 4 comprises two pressure gauges 41 which are arranged along with the direction of the air flow and are adjustable, the pressure gauges 41 are fixedly connected and communicated with the filter membrane holder 11, so that the real-time pressures of two positions can be observed, and the pressure can be adjusted at the same time, thereby avoiding the influence of excessive pressure difference on the collected soot flame and the damage of experimental instruments; the clamping seat 21, the capillary probe 22, the filter membrane holder 11 and the pressure gauge 41 form a soot collection sampling channel (which is a gas channel at the same time), when the device is used, the pressure gauge 41 on one side is connected with a vacuum pump (not shown in the figure) through the adapter port 5 and the hose, and the pressure gauge 41 on the other side is connected with an inert gas tank (not shown in the figure) through the adapter port 5 and the hose, for example, nitrogen, argon and the like.

As shown in fig. 2, the sampling unit 2 of the present invention includes a hollow holder 21, a capillary probe 22 with a sampling hole 221 is disposed on the holder 21, and the holder 21 is fixed on the holder 11.

In this embodiment, capillary probe 22 is capillary stainless steel probe or capillary quartz probe, capillary stainless steel probe or capillary quartz probe one end ring is equipped with external screw thread 222 or both ends ring is equipped with the unanimous external screw thread 222 of direction of rotation, cooperatees with the internal thread hole 211 that grip slipper 21 set up, can realize disposable installation and grip slipper 21 internal thread synchronous fit and realize convenient installation. The outer chamfer is arranged at the starting position of the internal thread hole 211 arranged on the clamping seat 21; the external diameter of the external thread 222 at the two ends of the capillary stainless steel probe or the capillary quartz probe is slightly smaller than the external diameter of the capillary stainless steel probe or the capillary quartz probe, and the external diameter is tightly matched with the internal threads of the clamping seats 21 at the two ends, so that the air tightness is ensured.

The sampling capillary probe (a capillary stainless steel probe or a capillary quartz probe) of the embodiment is thinner than a probe of a traditional sampling device, and the outer diameter of a sampling area is 0.2-2 mm. In the research of the Wangming bead & lt & ltresearch on carbon smoke microstructure, surface functional group and oxidability in methane diffusion flame & gt Doctoral degradation (2014), a capillary sampling system is adopted, a capillary probe with the diameter not less than 3mm is used as a sampling probe, the laminar diffusion flame is sampled, the flame shape of the laminar diffusion flame is larger, but the influence on the flame is larger due to the size of the probe which cannot be ignored, so that the collected carbon smoke has poorer crystallinity and oxidation activity; meanwhile, the experimental sampling device is not provided with a three-dimensional adjusting device, the adjustment is time-consuming and labor-consuming when the carbon smoke of flames with different heights is acquired, the whole process is very complex and time-consuming, and the precision is difficult to guarantee; and moreover, the test sampling device has no threads on the probe, the probe cannot be replaced according to the requirements of fuel and a combustor, and the problems of soot pollution, inaccurate detection result and the like are caused.

In the prior art, a reference object is selected for realizing accurate adjustment of sampling at different heights by a sampling device, and the sampling height is adjusted by aligning the sampling table and the reference object, but the reference object needs to be selected or adjusted during each adjustment, and the sampling device needs to be returned and aligned again, so that the whole process is very complex and time-consuming, and the accuracy is difficult to guarantee. In the invention, the clamping unit can be adjusted by adjusting three mutually combined and coordinated adjusters, and the adjustment can be freely and conveniently carried out in any direction of a three-dimensional space within a certain range; meanwhile, the adjusting disc of the adjusting system can be provided with scales, so that the adjusting amount of the adjusting system can be known, the adjusting system can be accurately adjusted to a preset position, and the adjusting system is simple, time-saving and has precision guarantee.

Aiming at the fact that a sampling device does not influence or reduces influence to the sampling object as much as possible, and the inadaptability of a non-contact method in the aspects of soot collection and analysis is combined, the contact position of a sampler and flame is reduced as much as possible at the present stage, so that the influence of the sampling device on the flame can be reduced. Aiming at avoiding the influence of the combustion products of the experimental fuel on the current experimental result when different fuels are used, the traditional method can only realize the sampling treatment of the combustion of one fuel, cannot be suitable for the experiment of replacing the combustion fuel, or can be replaced, but the operation process of the device is too complex and takes time, and is generally not suitable for the actual operation of the experiment.

When the capillary stainless steel probe or the capillary quartz probe has an external thread 222 around one end, a single holder 21 may be used to extend the free end of the capillary stainless steel probe or the capillary quartz probe into the flame to collect soot.

As shown in fig. 3 and 4, the filter unit 3 of the present invention includes a filter membrane holder 11, the filter membrane holder 11 has two filter membrane holding pieces 31, the filter membrane holding pieces 31 are fixed by bolts, a boss 311 is reserved on the surface of one of the filter membrane holding pieces 31, a groove 313 matched with the boss 311 is reserved on the surface of the corresponding other filter membrane holding piece 31, through holes are both arranged on the boss 311 and the groove 313, the boss 311 and the groove 313 are attached to each other, so as to ensure the air tightness of the whole filter unit 3, and firmly fix the filter membrane, a placing groove 312 is arranged on the boss 311, a filter membrane and a protection pad 32 are arranged in the placing groove 312, the protection pad 32 corresponds to the size of the filter membrane, and can well support the filter membrane to protect the filter membrane, and prevent the filter membrane from being damaged by the pressure difference of the air flow.

As shown in fig. 5 and 6, the adjusting and clamping unit 1 of the present invention includes a clamp 11, a first adjuster 12, a second adjuster 13 vertically orthogonally provided to the first adjuster 12, and a third adjuster 14 vertically orthogonally provided to the second adjuster 13, the clamp 11 being provided on an upper side surface of the first adjuster 12. The first adjustor 12, the second adjustor 13 and the third adjustor 14 adjust displacements in two directions respectively, can adjust four horizontal directions and vertical directions, and adjust the clamping unit 1 to move up and down and horizontally, so that the two capillary probes 22 and the clamping base 21 move precisely.

Further, the first adjuster 12, the second adjuster 13 and the third adjuster 14 have the same structure, the third adjuster 14 includes a first adjusting disc 142 and a second adjusting disc 141, a first scale 1427 is horizontally arranged on one side of the first adjusting disc 142, a first indication arrow 1411 is arranged on one side of the second adjusting disc 141, a first guide groove 1424 and a mounting hole 1422 are formed in the first adjusting disc 142, a rack sliding groove 1425 is formed at the bottom of the first guide groove 1424, a second transmission gear 1423 is arranged in the rack sliding groove 1425, an adjusting lever 1421 connected with the second transmission gear 1423 is arranged in the mounting hole 1422, and the adjusting lever 1421 drives the second transmission gear 1423 to rotate; the second adjusting disk 141 is provided with a first slide block 1413, the first slide block 1413 is provided with a second transmission rack 1414, the first slide block 1413 is embedded in the first guide groove 1424, and the first adjusting disk 142 and the second adjusting disk 141 are meshed and transmitted with the second transmission gear 1423 through the second transmission rack 1414, so that the horizontal adjustment of the second adjusting disk 141 relative to the first adjusting disk 142 is realized. More specifically, the adjustment lever 1421 is inserted into the mounting hole 1422, and when the adjustment lever 1421 is rotated, the second transmission gear 1423 is rotated.

In addition, the cross-sectional shape of the first guide groove 1424 is a dovetail structure, and the cross-sectional shape of the corresponding first slider 1413 is also a dovetail structure, but the first guide groove 1424 and the first slider 1413 may also have other structural shapes, such as a rectangular shape, a trapezoidal shape, and the like.

In order to make the second adjustment disc 141 slide more smoothly relative to the first adjustment disc 142, in an embodiment of the present invention, an auxiliary guide groove 1426 is formed on the first adjustment disc 142, an auxiliary guide slider 1412 is correspondingly disposed on the second adjustment disc 141, and the auxiliary guide slider 1412 is engaged in the auxiliary guide groove 1426.

In order to make the horizontal adjustment position of the experimental apparatus more accurate, a first scale 1427 is horizontally disposed on one side of the first adjustment disk 142, the minimum scale of the first scale 1427 is 0.1mm, a zero point is disposed at the middle position of the first scale 1427, correspondingly, a first indication arrow 1411 is disposed on one side of the second adjustment disk 141, the first indication arrow 1411 and the first scale 1427 are located on the same side, and when the first indication arrow 1411 is aligned with the zero point of the first scale 1427, this state can be said to return the adjuster to zero.

As shown in fig. 5, in order to adjust the vertical direction, the first actuator 12 and the second actuator 13 are connected, and an L-type connecting member 16 is connected between the middle position of the second adjusting plate 141 of the second actuator 13 and the first adjusting plate 142 of the first adjusting plate 142, wherein the relative position and the adjusting direction of the first actuator 12 and the second actuator 13 are different, and other parameters are consistent.

As shown in fig. 5 and 6, in order to adapt the experimental device to different experimental benches, an adjuster base 15 is arranged below the third adjuster 14, and the adjuster base 15 is fixedly connected with the third adjuster 14 through four screws to realize a stable state; the adjustable fixing base is arranged on the adjuster base 15 and is composed of two vertical fixing pieces which are distributed correspondingly, each vertical fixing piece is provided with an adjustable screw and located at a corresponding position, and the adjustable fixing base can be fixed on the experiment bench stably.

The regulator base 15 of this embodiment can convenient dismantlement and installation to combustor on possessing the optics platform is also applicable, dismantles regulator base 15 and gets off alright steadily and fix the experiment to the optics platform through four screw holes of reserving.

Example 2

The sampling method of the laminar flow flame soot collection and sampling device in the embodiment adopts the soot sampling device in the embodiment 1 to sample, adopts a set of symmetrically arranged adjusting clamping units 1, and the adjusting clamping units 1 do not comprise adjusting bases, and comprises the following steps:

step S101, opening a carbon filter membrane holder 11 of a filter unit 3 by using a wrench to adjust a bolt, taking out two filter membranes from a filter membrane box by using clean tweezers, respectively placing the two filter membranes on a filter membrane protection pad 32 which is cleaned and dried, sequentially arranging the filter membranes in the filter unit 3 in a mode that the filter membranes are arranged upwards and the protection pad 32 is arranged downwards according to the flowing direction of inert (including nitrogen or argon, and other inert gases), and then adjusting the bolt by using the wrench until a boss 311 is corresponding to and orderly with a groove 313, wherein filter membrane holding pieces 31 are tightly attached;

step S102, placing the adjusting clamping unit 1 on an optical platform, adjusting the distance between two screws on the clamp holder 11 and the movable edge of the clamp holder 11 to be equal to the length of the clamping seat 21, and then fixing the clamp holder 11; adjusting the horizontal distance from the adjusting rod 1421 on the second adjuster 13 to the two holders 21 to select the same length of the sampling capillary probe 22, and adjusting the adjusting rod 1421 on the first adjuster 12 to a preset height equal to the vertical position of the two holders 21, so as to align and height-adjust the two holders 21;

step S103, taking out the clean sampling capillary probe 22 with the external threads 222 at two ends, wherein the external diameter is 0.2mm, screwing the sampling capillary probe 22 into the internal thread holes 211 of the two clamping seats 21, and firstly adjusting the adjusting rod 1421 until the sampling hole 221 of the capillary probe 22 faces downwards; then adjusting the second adjuster 13 to adjust the sampling hole 221 of the capillary probe 22 to the horizontal position with the center of the flame of the burner;

step S104, the filtering unit 3, the sampling unit 2 and the pressure analysis and adjustment unit 4 are sequentially connected, a pressure gauge 41 on one side of the filtering unit 3 is connected with a vacuum pump through an adapter port 5 and a hose, and the pressure gauge 41 on the other side is connected with a nitrogen gas tank through the adapter port 5 and the hose;

s105, connecting pipelines of the burner, checking whether the gas pipelines leak gas or not, opening an inert gas tank and a vacuum pump, and adjusting a pressure gauge 41 to a preset pressure; introducing gas and oxidant gas, igniting flame, adjusting the third adjuster 14 to move the sampling capillary probe 22 into the flame for soot collection;

and S106, adjusting the regulator to move the sampling capillary probe 22 out of the flame after the soot is collected and the time is up, disassembling the lower filtering unit 3, and taking out the filter membrane to collect and concentrate for subsequent detection.

Example 3

The sampling method of sampling device is collected to laminar flow flame soot of this embodiment adopts the soot sampling device of embodiment 1 to sample, adopts a set of regulation clamping unit 1 of symmetry setting, adjusts clamping unit 1 including adjusting the base, and its step is:

step S102, fixing the regulator base 15 on a test bench; adjusting the distance of the clamper 11 to meet the length of the clamping seat 21, and then fixing the clamper 11; adjusting the horizontal distance from the adjusting rod 1421 on the second adjuster 13 to the two holders 21 to select the same length of the sampling capillary probe 22, and adjusting the adjusting rod 1421 on the first adjuster 12 to a preset height equal to the vertical position of the two holders 21, so as to align and height-adjust the two holders 21;

step S103, taking out the clean sampling capillary probe 22 with the external threads 222 at two ends, wherein the external diameter is 0.8mm, screwing the sampling capillary probe 22 into the internal thread holes 211 of the two clamping seats 21, and firstly adjusting the adjusting rod 1421 until the sampling hole 221 of the capillary probe 22 faces downwards; then adjusting the second adjuster 13 to adjust the sampling hole 221 of the capillary probe 22 to the horizontal position with the center of the flame of the burner;

step S104, the filtering unit 3, the sampling unit 2 and the pressure analysis and adjustment unit 4 are sequentially connected, a pressure gauge 41 on one side of the filtering unit 3 is connected with a vacuum pump through an adapter port 5 and a hose, and the pressure gauge 41 on the other side is connected with an argon gas tank through the adapter port 5 and the hose;

Example 4

The sampling method of the laminar flow flame soot collection and sampling device in the embodiment adopts the soot sampling device in the embodiment 1 to sample, adopts an adjusting clamping unit 1, and the adjusting clamping unit 1 does not comprise an adjusting base, and comprises the following steps:

step S102, placing the adjusting and clamping unit 1 on an optical platform, adjusting the distance of the clamping device 11 to meet the length of the clamping seat 21, and then fixing the clamping device 11; adjusting the horizontal distance from the adjusting rod 1421 on the second adjuster 13 to the holder 21 to select the same length of the sampling capillary probe 22, and adjusting the height from the adjusting rod 1421 on the first adjuster 12 to the preset height of the holder 21, such as the vertical position, to realize the alignment and height adjustment of the holder 21;

step S103, taking out the clean sampling capillary probe 22 with the external thread 222 at one end, wherein the external diameter is 1.2mm, screwing the sampling capillary probe 22 into the internal thread hole 211 of the clamping seat 21, and firstly adjusting the adjusting rod 1421 until the sampling hole 221 of the capillary probe 22 faces downwards; then adjusting the second adjuster 13 to adjust the sampling hole 221 of the capillary probe 22 to the horizontal position with the center of the flame of the burner;

Example 5

step S103, taking out a clean sampling capillary probe 22 with the outer diameter of 2mm, screwing the sampling capillary probe 22 into the internal thread holes 211 of the two clamping seats 21, and firstly adjusting the adjusting rod 1421 until the sampling hole 221 of the capillary probe 22 faces downwards; then adjusting the second adjuster 13 to adjust the sampling hole 221 of the capillary probe 22 to the horizontal position with the center of the flame of the burner;

Example 6

The sampling method of the laminar-flow-flame soot collection and sampling device in the embodiment is combined with embodiment 1, embodiment 2, embodiment 3, embodiment 4 and embodiment 5, liquid fuel n-heptane is used as fuel, the gasified fuel is sent to a burner (the embodiment adopts the laminar-flow-flame burner) through a heat preservation equipment pipeline to be combusted, soot is collected at the positions with the flame heights of 20mm, 40mm and 60mm respectively, the collected soot is placed in a glass slide groove 62 of a detection glass slide 63 of an XRD detection glass 6, the glass slide groove 62 is filled with 80-90% of the collected soot, then a cover glass 63 is covered to slightly shake to enable the soot to become loose and not to be deposited, the collected soot is placed into an X-ray photoelectron spectrometer to be detected, and the diffraction angle is set to be 10 degrees.

Taking the abscissa as Two-Theta, the unit as deg, and the abscissa as intensity (counts); the results are plotted in FIG. 8.

According to the detection result, the carbon smoke X-ray photoelectron spectrogram collected by the method has Two peaks (one large peak, one small peak, the first large peak appears, the second small peak appears, and the Two peaks all fall within the Two-Theta range of C), wherein the large peak is a characteristic peak, represents the unique characteristics of the detected substances and all falls within the X-ray photoelectron spectrogram range of C.

The characteristic peaks of X-ray photoelectron energy spectrograms for collecting soot at the positions of 20mm, 40mm and 60mm of flame height are sequentially increased, which shows that the crystallization degree is better and better, the influence on soot particles in the sampling process is small, and the coincidence with a real result is good.

Example 7

With reference to example 1, example 2, example 3, example 4 and example 5, n-heptane, a liquid fuel, was used as a fuel, gasified, sent to a burner (a laminar flow flame burner was used in this example) through a heat-insulating device pipeline for combustion, collected soot at the flame heights of 20mm, 40mm and 60mm, respectively, placed in a drying oven for sufficient drying to remove moisture in the soot sample and prevent the sample from adsorbing impurities, placed in a platinum crucible, weighed, and placed in a thermogravimetric analyzer for detection. The experiment used a steady temperature control program, setting a small temperature rise rate of 5 ℃/min (i.e., a temperature rise of about 0.083 ℃/sec); in order to ensure that the oxidation reaction is timely changed along with temperature rise, 10 percent of O by volume ratio is adopted₂+90％N₂The atmosphere assisted oxidation, using a suitable gas flow rate of 60 ml/min. And meanwhile, the mass change is detected every 1sec, so that the dynamic instantaneity of the detection result is realized.

The abscissa is time (time) in seconds (sec) and the abscissa is the residual proportion (MASS); the results are plotted in FIG. 9.

The detection result is combined to show that the mass of the soot sample is basically unchanged along with the increase of the temperature when the photoelectron energy spectrogram of the collected soot X-ray is firstly acquired, and the mass of the soot sample particles is basically unchanged before the temperature is increased to about 505 ℃; with the increase of the temperature, the mass of the soot sample particles is continuously reduced; when the temperature reached about 644 ℃, the soot sample particle mass was almost zero. Specific initial oxidation temperature T_i(. degree. C.), initial oxidation temperature T_i(° c) is as follows:

thermogravimetric analysis of carbon smoke sample particles collected at the positions with the flame heights of 20mm, 40mm and 60mm shows that the carbon smoke sample particles have good oxidation activity, the influence on the carbon smoke particles in the sampling process is small, and the coincidence with a real result is good.

The above examples are only preferred embodiments of the present invention, it should be noted that: it will be apparent to those skilled in the art that various modifications and equivalents can be made without departing from the spirit of the invention, and it is intended that all such modifications and equivalents fall within the scope of the invention as defined in the claims.

Claims

1. A laminar flame soot collection sampling device, comprising:

the adjusting and clamping unit (1) comprises a clamp holder (11), a first adjuster (12), a second adjuster (13) vertically and orthogonally arranged with the first adjuster (12), and a third adjuster (14) vertically and orthogonally arranged with the second adjuster (13), wherein the clamp holder (11) is arranged on the upper side surface of the first adjuster (12);

the sampling unit (2) comprises a hollow clamping seat (21), a capillary probe (22) provided with a sampling hole (221) is arranged on the clamping seat (21), and the clamping seat (21) is fixed on the clamp holder (11);

the filter unit (3) comprises a filter membrane holder (11), the filter membrane holder (11) is provided with at least two filter membrane clamping sheets (31), the filter membrane clamping sheets (31) are fixed through bolts, a boss (311) is reserved on the surface of one filter membrane clamping sheet (31), a groove (313) matched with the boss (311) is reserved on the surface of the corresponding other filter membrane clamping sheet (31), through holes are formed in the boss (311) and the groove (313), the boss (311) and the groove (313) are mutually attached, a placing groove (312) is formed in the boss (311), and a filter membrane is arranged in the placing groove (312);

the pressure analysis and adjustment unit (4) comprises two pressure gauges (41) which are arranged along the direction of the air flow and can be adjusted, and the pressure gauges (41) are fixedly connected and communicated with the filter membrane holder (11);

the clamping seat (21), the capillary probe (22), the filter membrane clamping device (11) and the pressure gauge (41) form a soot collection sampling channel, when the device is used, the pressure gauge (41) on one side is connected with a vacuum pump through the adapter port (5) and the hose, and the pressure gauge (41) on the other side is connected with an inert gas tank through the adapter port (5) and the hose.

2. The laminar flow flame soot collection and sampling device according to claim 1, wherein the first adjuster (12), the second adjuster (13) and the third adjuster (14) have the same structure, the third adjuster (14) comprises a first adjusting disc (142) and a second adjusting disc (141), the first adjusting disc (142) is provided with a first guide groove (1424) and a mounting hole (1422), the bottom of the first guide groove (1424) is provided with a rack runner (1425), the rack runner (1425) is provided with a second transmission gear (1423), the mounting hole (1422) is provided with an adjusting rod (1421) connected with the second transmission gear (1423), and the adjusting rod 1421 drives the second transmission gear (1423) to rotate; the second adjusting disk (141) is provided with a first sliding block (1413), the first sliding block (1413) is provided with a second transmission rack (1414), the first sliding block (1413) is embedded in the first guide groove (1424), the first adjusting disk (142) and the second adjusting disk (141) are in meshing transmission with the second transmission gear (1423) through the second transmission rack (1414), and horizontal adjustment of the second adjusting disk (141) relative to the first adjusting disk (142) is achieved.

3. A laminar flame soot collection and sampling device according to claim 2, wherein a first scale (1427) is horizontally arranged on one side of the first adjusting disk (142), and a first indication arrow (1411) is arranged on one side of the second adjusting disk (141).

4. The soot collecting and sampling device of the laminar flow flame as claimed in claim 3, wherein the first adjusting disk (142) is provided with an auxiliary guiding groove (1426), the second adjusting disk (141) is correspondingly provided with an auxiliary guiding slider (1412), and the auxiliary guiding slider (1412) is embedded in the auxiliary guiding groove (1426); the cross sections of the first guide groove (1424) and the first sliding block (1413) are both in a dovetail shape.

5. The laminar flame soot collection and sampling device according to claim 4, wherein the capillary probe (22) is a capillary stainless steel probe or a capillary quartz probe, and both ends of the capillary stainless steel probe or the capillary quartz probe are annularly provided with external threads (222) with consistent rotation directions, and are matched with an internal thread hole (211) arranged on the clamping seat.

6. The laminar flame soot collection and sampling device according to claim 5, wherein the internal thread hole (211) of the clamping seat (21) is externally chamfered at the beginning; the external diameter of the external threads (222) at the two ends of the capillary stainless steel probe or the capillary quartz probe is slightly smaller than the external diameter of the capillary stainless steel probe or the capillary quartz probe, and the external diameters of the external threads are tightly matched with the internal threads of the clamping seats (21) at the two ends.

7. A laminar flow flame soot collecting and sampling device according to claim 6, characterized in that a protection pad (32) is further provided in the placing groove (312), and the protection pad (32) corresponds to the size of the filter membrane.

8. A laminar flame soot collection and sampling device according to claim 1, wherein the adjusting clamp unit (1) further comprises an adjuster base (15), and the third adjuster (14) is arranged on the adjuster base (15) and fixed by bolts.

9. The sampling method of the laminar flame soot collecting and sampling device according to claim 7, characterized by comprising the following specific steps:

s101, opening a carbon filter membrane holder (11) of a filter unit (3), placing a filter membrane in a protection pad (32), sequentially arranging the filter membrane in the filter unit (3) in a mode that the filter membrane is arranged above the protection pad (32) and the protection pad is arranged below the protection pad (32) according to the flowing direction of inert atmosphere, adjusting bolts until a boss (311) and a groove (313) are correspondingly neat, and tightly attaching filter membrane holding pieces (31);

s102, placing the adjusting clamping unit (1) on an optical platform, adjusting the distance of a clamping device (11) to meet the length of a clamping seat (21), and then fixing the clamping device (11); adjusting the horizontal distance from an adjusting rod (1421) on the second adjuster (13) to the clamping seat (21) to be equal to the length of the selected sampling capillary probe (22), and adjusting the vertical position of the adjusting rod (1421) on the first adjuster (12) to the clamping seat (21) to be equal to the preset height;

step S103, taking out a clean sampling capillary probe (22), screwing the sampling capillary probe (22) into an internal thread hole (211) of a clamping seat (21), and firstly adjusting an adjusting rod (1421) until a sampling hole (221) of the capillary probe (22) faces downwards; then adjusting a second adjuster (13) to adjust a sampling hole (221) of the capillary probe (22) to be horizontal to the center of the flame of the burner;

step S104, sequentially connecting a filtering unit (3), a sampling unit (2) and a pressure analysis and adjustment unit (4), wherein a pressure gauge (41) on one side of the filtering unit (3) is connected with a vacuum pump through an adapter port (5) and a hose, and a pressure gauge (41) on the other side is connected with an inert gas tank through the adapter port (5) and the hose;

s105, connecting a pipeline of the combustor, checking whether the gas pipeline leaks gas or not, opening an inert gas tank and a vacuum pump, and adjusting a pressure gauge (41) to a preset pressure; introducing gas and oxidant gas, igniting flame, adjusting a third adjuster (14) to move a sampling capillary probe (22) into the flame for soot collection;

and S106, adjusting the regulator to move the sampling capillary probe (22) out of the flame after the soot is collected and the time is up, disassembling the filtering unit (3), and taking out the filter membrane to collect and concentrate for subsequent detection.

10. The sampling method of the laminar flame soot collecting and sampling device according to claim 8, characterized by comprising the following specific steps:

s102, fixing a regulator base (15) on a test bench; the distance of the clamp holder (11) is adjusted to meet the length of the clamp seat (21), and then the clamp holder (11) is fixed; adjusting the horizontal distance from an adjusting rod (1421) on the second adjuster (13) to the clamping seat (21) to be equal to the length of the selected sampling capillary probe (22), and adjusting the vertical position of the adjusting rod (1421) on the first adjuster (12) to the clamping seat (21) to be equal to the preset height;