Gas-solid mixture jet fire device

Abstract

The gas-solid mixture jet fire device described in the present invention comprises a combustible gas cylinder, a pressure reducing valve, a metal hose, an adapter, a stainless steel pipe, a gas flow controller and a flame arrester connected in sequence. The lower part of the burner passes through the feeder and is connected to the flame arrester through a gas transmission metal hose; an igniter is provided at the top of the burner; a support device for fixing the feeder is provided on the electronic balance, and a sand collection and weighing device is sleeved on the upper part of the burner. The present invention utilizes the Venturi effect to automatically suck in the sand accumulated at the side port of the burner and spray it out together with the gas. The gaseous fuel flow rate, the aperture size, the area of ​​the side port of the burner and the height of the sand accumulation in the feeder can control the amount of sand sucked in. The height of the sand accumulation in the feeder is supplemented and controlled by a conveyor belt, so as to form a continuous and stable gas-solid mixture jet flow; the size of the tube wall opening can be adjusted according to the specific size of the burner, and can be suitable for gas-solid jet experiments of solid particles of different sizes such as microns and millimeters.

Description

Technical Field

[0001] The invention belongs to the field of safe operation of long-distance natural gas transmission pipelines, and in particular relates to a gas-solid mixture jet fire device. Background Art

[0002] Jet fire is also called high-speed jet diffusion flame, such as jet flame caused by chemical tank leakage, combustion flame of flare system for waste gas treatment, jet combustion caused by damaged gas pipeline leakage, and the thermal radiation generated by it poses a great threat to surrounding personnel and buildings. When buried natural gas pipelines pass through desertified areas, forests, or during oil and gas production, the jet fire induced by leakage is often accompanied by a large amount of sand and dust during propagation. At this time, the flame thermal radiation is the radiation of gaseous fuel combustion products and sand and dust. At the same time, sand and dust will affect the combustion characteristics such as the shape, temperature, and speed of the jet flame.

[0003] Existing jet fire experimental devices only consider the jet flow of gaseous fuel. For example, Chinese patent CN109682924A discloses an experimental device for igniting a jet fire formed by leakage of a high-pressure gas pipeline. The device uses a gas source system, a burner, a data acquisition system and a flame characteristic characterization expansion module to study the combustion dynamics process of the gaseous fuel being ignited to form a jet fire. However, the device can only study gaseous jet fires and does not consider the situation where sand and dust are entrained into the flame. Therefore, it is impossible to conduct experiments on gas-solid mixture jet fires on this experimental device.

[0004] At present, the research on gas-solid mixture combustion phenomenon mainly involves coal dust gas explosion in coal mining, and flame propagation and explosion during dust cloud combustion. The gas-solid two-phase generation devices they built are all for gas-solid premixed flames. For example, the predecessors designed a device for continuous combustion of dust clouds in open space based on the principle of spiral feeding. The combustion medium is zirconium powder and air, which belongs to gas-solid premixed flames and is not applicable to diffusion jet flames.

[0005] The feeding methods of existing gas-solid injection devices can be divided into active and passive types. The active spiral vibrating feeder (reference: Wang Qiuhong. Experimental study on transient flame and continuous jet flame characteristics of zirconium powder cloud [D]. University of Science and Technology of China, 2012) is mainly composed of A-01 motor reducer, A-02 feeding bin, and A-03 spiral. The particles produce relative displacement under the action of gravity and external spiral driving force to feed. The specific structure is as follows Figure 1 As shown; the active gas-solid injection feeder (reference: Yu Weiwei. Experimental study on ignition characteristics of coal powder particle group jet [D]. Tsinghua University. 2013) is mainly composed of A-04 motor base, A-05 stepper motor, and A-06 injector. The solid particles are placed in the injector and fed under the drive of the stepper motor. The specific structure is as follows Figure 2As shown. For these two active feeding devices, solid particles need to be mixed with the gas-solid mixture in a mixing chamber by airflow, and then the solids are carried out of the burner together by the secondary airflow. Obviously, the continuous feed rate of these devices cannot be accurately controlled, and the experimental test repeatability is poor. If precision is required, the economic cost is high. The passive fluidized feeder is mainly composed of A-07 feeding pipe, A-08 fine powder pipe, and A-09 air supply pipe. The feeding amount is mainly adjusted by changing the height of the feeding pipe and the airflow flow rate. The structure is as follows Figure 3 As shown, it is obvious that this device cannot form a long-lasting and continuous gas-solid mixture jet fire. Summary of the invention

[0006] In view of the fact that the above-mentioned existing jet fire experimental devices can only study the jet fire formed by gaseous fuel, and the gas-solid jet generating device has the disadvantages of discontinuity and poor test repeatability, the present invention provides a gas-solid mixture jet fire device, which can realize continuous gas-solid mixture jet flow, and is used to study the jet fire combustion characteristics and thermal disasters when underground natural gas pipelines leak in desertified areas and are accompanied by sand entrainment.

[0007] The gas-solid mixture jet fire device described in the present invention adopts the following technical scheme: comprising a gas-solid mixture jet fire simulation device, a sand collection and weighing device, a conveying device, a supporting device, a gas alarm, an electronic balance and a computer;

[0008] The gas-solid mixture jet fire simulation device includes a flammable gas cylinder, a pressure reducing valve, a metal hose, a adapter, a stainless steel pipe, a gas mass flow controller, a flame arrester, a burner, a feeder and an igniter;

[0009] The outlet end of the flammable gas cylinder is equipped with a pressure reducing valve, which is connected to the air inlet end of the stainless steel pipe through a metal hose and an adapter; a gas mass flow controller is installed in the middle section of the stainless steel pipe, and a flame arrester is installed at the end of the stainless steel pipe;

[0010] The lower part of the burner vertically passes through the feeder and is connected to the flame arrester through a gas delivery metal hose;

[0011] A conveying device for conveying sand is provided at the upper entrance of the feeder;

[0012] An igniter is provided at the top of the burner;

[0013] The support device is installed below the feeder and located on the electronic balance, and a sand collection and weighing device is sleeved on the upper part of the burner;

[0014] A gas alarm for detecting air tightness is also placed at the outlet of the flammable gas cylinder;

[0015] The gas mass flow controller, electronic balance and sand collection and weighing device are connected to the computer via data cables respectively.

[0016] The feeder is continuously fed with materials through the conveying device, so as to ensure that the sand accumulation height in the feeder remains relatively stable, and reduce the influence of the change of sand accumulation in the feeder on the sand suction rate. The feeder is replenished with sand, and the continuity of the gas-solid injection flow is also ensured.

[0017] Furthermore, the burner is a vertical tubular structure, which includes a burner body, an externally threaded pipe and a orifice plate. The lower end of the burner body is connected to the externally threaded pipe, and the gas delivery metal hose is threadedly connected to the externally threaded pipe. The orifice plate is arranged in the lower section inside the burner body and is perpendicular to its central axis. A center hole is opened in the center of the orifice plate, and more than three tube wall openings are opened on the tube wall of the burner body above the orifice plate around its central axis.

[0018] Furthermore, the length of the burner is L, the inner diameter is D, the outer diameter is D1, and the distance from the bottom of the orifice plate to the top of the burner body is The distance from the top of the orifice plate to the top of the tube wall opening is D, and the thickness of the orifice plate and the diameter of the center hole of the orifice plate are The rectangular tube wall opening length is

[0019] Furthermore, the feeder is a truncated funnel-shaped structure with a horizontal bottom. A nozzle is provided at the center of the bottom of the feeder, and a connecting portion extends vertically downward from the nozzle. The burner passes through the nozzle below from the upper part of the feeder and makes the bottom end of the center hole of the orifice plate flush with the bottom of the feeder. A transparent threaded hole is provided on the side wall of the connecting portion, and the bottom of the bolt threadedly connected to the threaded hole is supported against the tube wall of the burner body, so that the nozzle presses the burner or separates from the burner.

[0020] Furthermore, the height of the feeder is 6D1, the diameter of its upper inlet is 10D1, the diameter of its bottom is 3D1, and the diameter of its nozzle is D1.

[0021] Furthermore, the supporting device includes a cross bar, a telescopic vertical rod, and a reinforcement disc. The cross bars are symmetrically fixed on both sides of the feeder. Two telescopic vertical rods with adjustable lengths are symmetrically installed on the reinforcement disc. The two cross bars are respectively connected and fixed to the two telescopic vertical rods by bolts.

[0022] Furthermore, the sand collection and weighing device includes a tray, a vertical support and a pressure sensor. The tray is sleeved on the upper part of the burner and has a gap with the outer wall of the burner without contact. The tray is supported by a telescopic rod support with adjustable length below it. A pressure sensor is installed at the bottom of the telescopic rod support, and the pressure sensor is connected to a computer.

[0023] The steps for conducting an experiment using the above device are:

[0024] 1) Fill the feeder with sand;

[0025] 2) Turn on the gas alarm to test the gas tightness of the device and adjust the gas mass flow controller;

[0026] 3) Open the pressure reducing valve of the combustible gas cylinder to allow the combustible gas to flow through the device pipeline and spray out from the top of the burner. When the gas mass flow controller is stable, immediately ignite the top of the burner with the igniter.

[0027] The present invention is based on the Venturi principle and proposes a method of utilizing gaseous fuel to flow through a contraction section to form a high-speed airflow, so that solid particles are automatically rolled into the airflow from the side holes of the burner under "negative pressure", and the sand feeding rate can be controlled by changing the gaseous fuel flow rate, the hole size, the opening area of ​​the side holes of the burner and the sand accumulation height in the feeder. At the same time, continuous feeding is carried out through a conveyor belt, and finally a continuous gas-solid mixture jet flow is realized, which is ignited as a gas-solid mixture jet fire.

[0028] Compared with the existing jet fire test device and gas-solid jet generation device, the beneficial effects of the present invention are:

[0029] 1. It can study the combustion characteristics of gas-solid mixture jet fire;

[0030] Second, the gas-solid injection device uses the orifice plate inside the burner to produce the Venturi effect. The negative pressure generated automatically sucks the sand accumulated at the side port of the burner and ejects it together with the gas. The size of the orifice plate, the area of ​​the side port of the burner (i.e., the pipe wall port) and the height of the sand accumulation in the feeder can control the feeding amount of the sand. It is simple, convenient and low-cost. The feeder is supplemented with material by a conveying device to control the height of the sand accumulation, which can form a continuous and stable gas-solid mixture injection flow;

[0031] 3. The size of the burner side opening can be adjusted according to the specific size of the burner, which can be used for gas-solid injection experiments of solid particles of different sizes such as microns and millimeters. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments in conjunction with the accompanying drawings.

[0033] Figure 1 This is a schematic diagram of the structure of an active spiral vibrating feeder;

[0034] Figure 2 It is a structural schematic diagram of an active gas-solid injection feeder;

[0035] Figure 3 It is a schematic diagram of the structure of a passive fluidized feeder;

[0036] Figure 4 It is a schematic diagram of the main structure of the present invention;

[0037] Figure 5 is a schematic diagram of the burner structure;

[0038] Figure 6 This is a schematic diagram of the sand feeding structure of the feeder;

[0039] Figure 7 This is a diagram of the fire effect of gas-solid mixture jet.

[0040] Among them, A-01 motor reducer, A-02 feeding bin, A-03 screw, A-04 motor seat, A-05 stepper motor, A-06 syringe, A-07 feeding tube, A-08 fine powder tube, A-09 air supply tube;

[0041] 1-gas-solid mixture jet fire simulation device, 101-flammable gas cylinder, 102-pressure reducing valve, 103-metal hose, 104-stainless steel pipe, 105-gas mass flow controller, 106-flame arrester, 107-burner, 1071-burner body, 1072-external threaded pipe, 1073-orifice plate, 1074-tube wall opening, 108-feeder, 1081 connecting part, 1082-sand, 1083-bolt, 109-igniter, 110-gas transmission metal hose, 111-adapter, 2-sand collection and weighing device, 21-tray, 22-telescopic rod support, 23-pressure sensor, 3-transmission device, 4-support device, 41-cross bar, 42-telescopic vertical rod, 43-reinforcement disc, 5-electronic balance, 6-computer, 7-gas alarm. DETAILED DESCRIPTION

[0042] like Figure 4As shown, a structural device for a gas-solid mixture jet fire comprises a gas-solid mixture jet fire simulation device 1, a sand collection and weighing device 2, a conveying device 3, a supporting device 4, an electronic balance 5, a computer 6 and a gas alarm 7; wherein, the gas-solid mixture jet fire simulation device 1 comprises a combustible gas cylinder 101, a pressure reducing valve 102, a metal hose 103, a stainless steel pipe 104, a gas mass flow controller 105, a flame arrester 106, a burner 107, a feeder 108, and an igniter 109, wherein the outlet of the combustible gas cylinder 101 is provided with a pressure reducing valve 102, one end of the metal hose 103 is connected to the pressure reducing valve 102, and the other end is connected to the gas inlet end of the stainless steel pipe 104 through an adapter, the middle section of the stainless steel pipe 104 is provided with a gas mass flow controller 105, and the end of the stainless steel pipe 104 is provided with a flame arrester 106; the lower part of the burner 107 vertically penetrates the feeder 108 and is connected to the flame arrester 106 through a gas transmission metal hose 110; the burner 1 An igniter 109 is provided at the top of 07; a conveying device 3 for conveying sand is provided at the upper entrance of the feeder; a supporting device 4 for fixing and supporting the feeder 108 is installed below the feeder 108, and the supporting device 4 includes a cross bar 41, a telescopic vertical rod 42 and a reinforcing disc 43. Cross bars 41 are provided at the symmetrical ends of both sides of the feeder 108. The two cross bars are preferably connected to the feeder by welding, and are respectively connected to the two telescopic vertical rods 42 below them by bolts. The lower parts of the two telescopic vertical rods are fixed on the reinforcing disc 43, which can prevent the feeder from shaking during the experiment and affecting the experimental results. The entire supporting device 4 is placed together on an electronic balance 5 for weighing, and a sand collecting and weighing device 2 is sleeved on the upper part of the burner 107; the gas mass flow control 105, the electronic balance 5, and the sand collecting and weighing device 2 are respectively connected to the computer 6 through a data cable; a gas alarm 7 for detecting air tightness is also placed at the outlet of the combustible gas cylinder.

[0043] In this embodiment, the combustible gas cylinder uses 30kg standard high-purity (>99.9%) canned propane, and the pressure reducing valve is connected to the gas cylinder to maintain a stable pressure of the gas when it is used. A gas mass flow controller is installed in the middle section of the stainless steel pipe to adjust the gas flow rate and accurately measure the gas volume flow rate, pressure and temperature in the pipeline. The flame arrester used in this embodiment is a ferrule-type flame arrester, which is installed at the end of the stainless steel pipe to prevent the backfire from spreading in the pipeline; the igniter is an electronic pulse ignition gun, which can generate continuous electric sparks. The length of the ignition gun is adjustable and bendable to ensure the safety of ignition; the electronic balance model is QuinTIXQ5102, with a maximum load of 5Kg and an accuracy of 0.01g. One data point is recorded per second, and the fully loaded feeder, burner, and support frame are placed on the electronic balance together to measure the real-time data value of the remaining mass of sand in the funnel after the experiment begins.

[0044] The conveying device used in the embodiment is a linear feeder in the prior art, which is placed on a workbench. The linear feeder mainly includes a linear track, an electromagnet, a spring sheet and a controller. The principle is to connect the electromagnet to 220v AC to make it vibrate, and the electromagnet drives the direct track to move through the spring sheet, thereby achieving the purpose of linear feeding. Turn on the controller of the feeder, and adjust the half-wave, full-wave or voltage, and the frequency can achieve the speed and stable transmission of the straight vibrator. The end of the linear track is directly above the center of the feeder, and the feed is manually added from the other end of the feeder track. After debugging, the transmission speed and the manual feeding speed can be optimally matched, thereby ensuring that the sand accumulation height in the feeder remains relatively stable and reducing the influence of the change in the amount of sand accumulation in the feeder on the sand entrainment rate. The feeder is supplemented with sand, and the continuity of the gas-solid injection flow is also guaranteed. Conveying devices of other structures can also be used as long as the purpose of conveying sand can be achieved. In different experiments, coal powder, metal dust, flour, etc. can be used instead of sand.

[0045] like Figure 5 As shown, the burner 107 is preferably a vertical tubular structure, which includes a burner body 1071, an external threaded tube 1072 and an orifice plate 1073. Preferably, the burner body 1071 and the external threaded tube 1072 at its lower end are integrally formed, and are seamlessly connected to the gas delivery metal hose 111 through the external threaded tube; the orifice plate 1073 is arranged inside the burner body 1071 and located in its lower section, a center hole is opened in the center of the orifice plate 1073, and the orifice plate is perpendicular to the central axis of the burner body; at least three tube wall openings 1074 are opened symmetrically around its central axis on the tube wall of the burner body 1071 above the orifice plate.

[0046] Preferably, the length of the burner 107 is L, its inner diameter is D, and its outer diameter is D1; ​​the distance between the bottom of the orifice plate and the top of the burner body is The distance from the bottom of the orifice plate 1073 to the top of the tube wall opening 1074 is D. To reduce the resistance caused by the thickness of the orifice plate, the thickness of the orifice plate and the diameter of the center hole of the orifice plate are both The length of the tube wall opening is The width of the tube wall opening is determined by the inner diameter D of the burner and the number of the tube wall openings; under the negative pressure generated by the high-speed airflow passing through the center of the orifice plate, the accumulated solid particles are automatically sucked into the high-speed airflow inside the burner from the side tube wall openings.

[0047] Among them, due to the limitation of the shape and size of the burner, the tube wall opening is designed to be rectangular, and its area can be optimized compared with other shapes. Of course, the tube wall opening can also be other shapes; when the opening area of ​​each tube wall opening 1074 is the same, three tube wall openings are opened equidistantly along the central axis of the burner, and the local resistance is optimal; the cross-section of the burner, the orifice plate and the center hole of the orifice plate can also be deformed from a circle to other polygonal structures; the relative position of the burner tube wall opening and the orifice plate can also change.

[0048] like Figure 6 The feeder 108 is a truncated funnel-shaped structure, whose bottom is horizontal and a nozzle is provided at the center of the bottom. The nozzle has a connecting portion 1081 extending vertically downward. The burner passes through the nozzle below from the upper part of the funnel and makes the bottom end of the center hole of the orifice plate 1073 flush with the bottom of the feeder 108. A transparent threaded hole is provided on the side wall of the connecting portion 1081. A bolt 1083 matching the threaded hole passes through the threaded hole and then supports the tube wall of the burner body. The bolt is tightened inward to press the nozzle against the burner, and the bolt is loosened outward to move the burner up and down, which is convenient for filling and collecting sand during the experiment.

[0049] The height of the feeder is 6D1, the diameter of the upper inlet is 10D1, the bottom diameter is 3D1, and the diameter of the nozzle is D1. The feeder is made of 304 stainless steel, and the welding parts are polished to ensure smooth inner wall and reduce friction.

[0050] The sand collection and weighing device 2 includes a tray 21, a telescopic rod support 22 and a pressure sensor 23. The tray is sleeved on the upper part of the burner and has no contact with the outer wall of the burner to prevent the tray 21 from contacting the burner and affecting the weighing. The tray is fixedly supported by three telescopic rod supports with adjustable lengths below it. Three pressure sensors connected to a computer are placed under each telescopic rod support to measure the real-time data value of the sand mass ejected from the burner during the experiment.

[0051] The design principle of the device of the present invention is: according to the continuity equation and Bernoulli equation

[0052] S1V1=S2V2=Q (1)

[0053]

[0054] Among them, S1, V1, P1, and Z1 are the cross-sectional area, wind speed, pressure, and height of the burner inlet, respectively; S2, V2, P2, and Z2 are the cross-sectional area, wind speed, pressure, and height of the orifice plate center hole outlet, respectively; g is the gas constant, ρ is the gas density, which is assumed to be unchanged, and Q is the volume flow rate of the gas flowing through the burner.

[0055] The density of propane is small and the distance from the burner inlet to the orifice plate is small, so the potential pressure is negligible. From equation (1), it can be seen that the velocity V2 of the same flow rate gas will increase when passing through the center S2 of an orifice plate with a very small cross-section. According to equation (2), it can be deduced that P2 becomes smaller, and a vacuum will be generated at the center outlet of the orifice plate.

[0056] The gas-solid mixture jet fire device utilizes the above-mentioned Venturi effect. There is an orifice plate inside the burner, and there is a central hole in the center of the orifice plate to produce the Venturi effect. The ratio of the central hole to the burner nozzle diameter is 1 / 10. The Venturi effect refers to the flowing gas entering from the entrance of the Venturi tube. After passing through a section with a very small cross-section, the flow rate of the gas increases and the pressure suddenly decreases. At this time, a vacuum is generated at the entrance of the adsorption chamber, causing the sand accumulated around the feeder to be sucked into the burner and ejected from the burner outlet together with the high-speed flowing gas, forming an effect in which the gas-solid mixture is ejected upward together. If the gas is flammable, it will form a gas-solid mixture jet fire after encountering an ignition source.

[0057] When the structural device of a gas-solid mixture jet fire described in the present invention is in operation, the feeder is first filled with sand 1082, the gas alarm is turned on to detect the gas of the device, the gas mass flow controller is adjusted according to the experimental requirements, and then the pressure reducing valve of the propane cylinder is opened to make propane flow through the metal hose 103, the stainless steel pipe 104, the gas mass flow controller 105, the flame arrester 106, and the gas transmission metal soft 111 in sequence, and then reach the top outlet of the burner after passing through the orifice plate. The propane forms a negative pressure in the central hole of the orifice plate, and the sand enters the burner body from the side of the pipe wall opening under the suction effect of the negative pressure, and is carried to the top outlet of the burner together with the propane gas flow. When the gas mass flow controller is stable, the burner outlet is immediately ignited with an igniter; the conveying device 3 is turned on to supplement the sand 1082 in the feeder to ensure the formation of a stable and continuous gas-solid mixture jet fire. The pipe wall openings opened on the burner can change the area and number according to the experimental working conditions to form different sand feeding speeds.

[0058] The sand ejection quality is measured as follows:

[0059] After filling the feeder with sand, adjust the position of the tray (so that it is not in contact with the burner) and return the readings on the electronic balance and pressure sensor to zero.

[0060] The mass transmitted by the conveyor belt is recorded as m1, the reading displayed on the electronic balance is recorded as m2, and the reading displayed on the pressure sensor is recorded as m3.

[0061] ①Do not start the conveyor belt, the electronic balance reading is negative, at this time -m2 = m3;

[0062] ② Start the conveyor belt. If the conveyor belt conveying mass = sand ejection mass, and m2 is zero, then m1 = m3. (Ensure that the sand in the funnel is in a relatively stable state), and take the reading on the sensor as the sand ejection mass.

[0063] The following application example is the generation of gas-solid mixture jet fire. During the experiment, the parameters were set as follows:

[0064] The total length of the burner is 250mm, the inner diameter is 10mm, the thickness of the orifice plate is 1mm, the diameter of the center hole is 1mm, the orifice plate is 120mm away from the top of the burner, and there are three axisymmetric rectangular openings (9mm long and 7mm wide) on the side of the burner. Figure 7 (a) The propane gas flow rate used was 13 slpm, and the sand used was 120 mesh white quartz sand; Figure 7 (b) The propane gas flow rate used was 15 slpm and the sand was 80 mesh white quartz sand.

[0065] Figure 7 (a) and Figure 7 (b) is a diagram of the jet flame after propane gas carrying sand is ejected out of the burner and ignited by an electronic pulse ignition gun, which shows that this device can produce a gas-solid mixture jet fire. Different propane gas flow rates and different sand mesh sizes cause corresponding changes in the flame shape. Figure 7 (a) When the propane gas flow rate is 13slpm and the sand particle size is 120 mesh (125 microns), white quartz sand can be clearly seen above the burner. A strip-shaped sand column can be clearly seen, and a reddish flame can be seen above the sand column. Under this condition, the sand particle size is small, the entrainment volume is large, and the sand concentration is high. The injection distance is small due to gravity. The high-concentration sand in the sand column isolates the contact between the propane gas and the air, so there is no flame in this section. Without the influence of sand above the sand column, the main flame appears red. Figure 7 (b) A propane gas flow rate of 15slpm and white quartz sand with a sand particle size of 80 mesh (175 microns) were selected. A blue flame appeared above the burner. Under this condition, the flow rate is large, the sand spray distance is large, the sand particle size is large, and the suction volume is small, so the concentration is low. The propane concentration is high, and the sand isolates part of the air. The propane burns incompletely, and a blue flame appears. The upper part burns fully, and the main body of the flame is yellow.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to be a further limitation of the present invention. All equivalent changes made using the contents of the present specification and drawings are within the protection scope of the present invention.

Claims

1. A gas-solid mixture jet fire device, characterized in that: It includes a gas-solid mixture jet fire simulation device, a sand collection and weighing device, a conveying device, a supporting device, a gas alarm, an electronic balance and a computer; wherein the gas-solid mixture jet fire simulation device includes a flammable gas cylinder, a pressure reducing valve, a metal hose, a stainless steel pipe, a gas mass flow controller, a flame arrester, a burner, a feeder and an igniter; The outlet end of the flammable gas cylinder is equipped with a pressure reducing valve, which is connected to the air inlet end of the stainless steel pipe through a metal hose and an adapter in turn; a gas mass flow controller is installed in the middle section of the stainless steel pipe, and a flame arrester is installed at the end of the stainless steel pipe; The lower part of the burner passes vertically through the feeder and is connected to the flame arrester through a gas delivery metal hose; a conveying device for conveying sand is provided at the upper inlet of the feeder; An igniter is provided at the top of the burner; The support device is installed below the feeder and located on the electronic balance, and a sand collection and weighing device is sleeved on the upper part of the burner; A gas alarm for detecting air tightness is also placed at the outlet of the flammable gas cylinder; The gas mass flow controller, electronic balance, and sand collection and weighing device are connected to the computer via data cables; The feeder is a truncated funnel-shaped structure, the bottom of which is horizontal, a nozzle is provided at the center of the bottom of the feeder, the nozzle extends vertically downward with a connecting portion, the burner passes through the nozzle below from the upper part of the feeder and makes the bottom end of the center hole of the orifice plate flush with the bottom of the feeder, a transparent threaded hole is provided on the side wall of the connecting portion, and the bottom of the bolt threadedly connected to the threaded hole is supported against the tube wall of the burner body, so that the nozzle presses the burner or separates from the burner; The burner is a vertical tubular structure, which includes a burner body, an externally threaded pipe and a perforated plate. The lower end of the burner body is fixedly provided with an externally threaded pipe, the gas delivery metal hose is threadedly connected to the externally threaded pipe, the perforated plate is arranged in the lower section of the burner body and is perpendicular to its central axis, a central hole is opened in the center of the perforated plate, and more than three pipe wall openings are opened on the pipe wall of the burner body above the perforated plate around its central axis; The flowing gas generates a strong negative pressure through the center of the orifice plate, causing the sand on the conveying device to be automatically sucked into the high-speed airflow inside the burner from the pipe wall opening.

2. A gas-solid mixture jet fire device according to claim 1, characterized in that: The length of the burner is L, its inner diameter is D, its outer diameter is D1, and the distance from the bottom of the orifice plate to the top of the burner body is The distance from the top of the orifice plate to the top of the tube wall opening is D, and the thickness of the orifice plate and the diameter of the center hole of the orifice plate are The length of the tube wall opening is 3. A gas-solid mixture jet fire device according to claim 1, characterized in that: The height of the feeder is 6D1, the diameter of its upper inlet is 10D1, the diameter of its bottom is 3D1, and the diameter of its nozzle is D1.

4. A gas-solid mixture jet fire device according to claim 1, characterized in that: The supporting device includes a cross bar, a telescopic vertical rod, and a reinforcement disc. The cross bars are symmetrically fixed on both sides of the feeder. Two telescopic vertical rods are symmetrically installed on the reinforcement disc. The two cross bars are respectively connected and fixed to the two telescopic vertical rods by bolts.

5. The gas-solid mixture jet fire device according to claim 1, characterized in that: The sand collection and weighing device includes a tray, a telescopic rod support and a pressure sensor. The tray is sleeved on the upper part of the burner and a gap is left between the tray and the outer wall of the burner. The tray is supported by the telescopic rod support below it. A pressure sensor is installed at the bottom of the telescopic rod support, and the pressure sensor is connected to a computer.

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