A vortex height and intensity independently adjustable fire whirl experiment device

Abstract

The application is suitable for the field of fire safety technology, and provides a fire whirlwind experimental device with independently adjustable vortex height and strength, which comprises a control cabinet, a rotating gauze curtain, an experimental table, a gauze curtain rotating system and a table lifting system, the rotating gauze curtain is arranged at the top end of the control cabinet, the experimental table is arranged inside the rotating gauze curtain to place oil pans or burners of different sizes, the gauze curtain rotating system is arranged on the control cabinet and connected with the rotating gauze curtain, the gauze curtain rotating system drives the rotating gauze curtain to rotate when working, and the table lifting system is arranged inside the control cabinet and connected with the experimental table at the top end to ensure that the experimental table vertically lifts, the device can simulate the fire whirlwind under different vortex distribution conditions in nature, and through experimental simulation and theoretical analysis, the influence of the vortex on the dynamic evolution law and mechanism of the fire whirlwind is revealed, thereby providing a scientific basis for the prediction and early warning technology of the fire whirlwind.

Description

Technical Field

[0001] This invention belongs to the field of fire safety technology, and in particular relates to a fire cyclone experimental device with independently adjustable vortex height and intensity. Background Technology

[0002] Fire whirls are a typical extreme fire behavior in forest-urban boundary fires. They are generated by the interaction between the rotating flow field around the flame and the fire plume. The formation of fire whirls leads to an increase in flame temperature, a significant increase in external radiation, and an increase in axial velocity. This can easily induce long-distance flying fires and generate new ignition points, thereby accelerating the spread of the fire. It may also trap firefighters in the fire scene and endanger their personal safety.

[0003] Generating vortices, or rotating flow fields around a flame, are essential for the formation of fire cyclones. Characterizing generating vortices requires two parameters: the intensity of the generating vortex and the vertical height of the vortex region. Currently, laboratory devices for inducing generating vortices are mainly divided into two categories: one is a rotating gauze-type device, which mechanically drives the gauze to rotate, thereby generating a rotating flow field; the other is a fixed frame type device, in which the surrounding airflow enters the chamber in a specific direction under the action of pressure difference through the buoyant flame at the center of the device, forming a rotating airflow. Both of these types focus on the circulation, that is, the influence of the generating vortex intensity on the combustion dynamics of fire cyclones, and rarely involve the influence of the generating vortex height.

[0004] However, in nature, when wind sweeps across the ground, the shear motion of the fluid generates vorticity. Through viscous diffusion, the boundary vorticity migrates into the interior of the fluid to form a free vortex layer. The vortex layer induces vortex formation, forming a concentrated vortex. Fire cyclones are typical concentrated vortices. Due to the limited height of the free vortex layer, most of the vorticity in the planetary boundary layer exists within a range of 1 meter above the ground. In order to gain a deeper understanding of the formation and evolution of fire cyclones in nature, this application provides a fire cyclone experimental device with independently adjustable generated vortex height and intensity to conduct research on the mechanism of generated vortex on the formation and stability of fire cyclones. Summary of the Invention

[0005] The purpose of this invention is to provide a fire cyclone experimental device with independently adjustable vortex height and intensity, aiming to solve the problems existing in the background art.

[0006] The present invention is implemented as follows: an experimental device for generating fire cyclones with independently adjustable vortex height and intensity, comprising a control cabinet, and further comprising:

[0007] A rotating gauze curtain, which is positioned at the top of the control cabinet;

[0008] The experimental table is located inside the rotating screen and is used to place oil pans or burners of different sizes.

[0009] The yarn screen rotating system is arranged on the control cabinet and connected with the rotating yarn screen and drives the rotating yarn screen to rotate when the yarn screen rotating system works.

[0010] The table lifting system is arranged inside the control cabinet and the top end of the table lifting system is connected with the experiment table to ensure the vertical lifting of the experiment table.

[0011] Preferably, the experiment table comprises a steel plate and a fireproof plate.

[0012] The steel plate is fixedly installed inside the rotating yarn screen and the fireproof plate is connected with the steel plate through the internal hexagonal bolt.

[0013] A circular hole is arranged at the center of the steel plate and the fireproof plate and the diameter of the circular hole is 50 cm.

[0014] Preferably, the yarn screen rotating system comprises a driving wheel, a slewing support bearing, a speed reducer and a driving wheel servo motor.

[0015] The slewing support bearing is installed in the middle of the top end of the control cabinet and is also connected with the rotating yarn screen through the bolt.

[0016] The driving wheel, the speed reducer and the driving wheel servo motor are arranged inside the control cabinet, the driving wheel is connected with the slewing support bearing and drives the slewing support bearing and the rotating yarn screen to move around the oil pan or the burner through the arranged speed reducer and the driving wheel when the driving wheel servo motor works.

[0017] Preferably, the driving wheel servo motor is electrically connected with the rotating control panel arranged outside the control cabinet and sends the control signal to the driving wheel servo motor through the rotating control panel to adjust the rotating speed and direction of the slewing support bearing.

[0018] Preferably, the table lifting system comprises a driving screw servo motor, a guide rod servo motor, a driving screw and a guide rod.

[0019] Two driving screws and guide rods are arranged, the top ends of the driving screws and the guide rods are connected with the bottom of the experiment table.

[0020] The driving screw is driven by the driving screw servo motor arranged on the side to realize the lifting of the experiment table and the guide rod is driven by the guide rod servo motor arranged on the side to ensure the vertical movement of the experiment table.

[0021] The driving screw servo motor and the guide rod servo motor are also electrically connected with the lifting control panel arranged on the control cabinet.

[0022] Preferably, the bottom end of the guide rod is provided with a light shielding element.

[0023] The control cabinet has two photoelectric sensors arranged vertically inside, and the two photoelectric sensors are aligned with the light-shielding element.

[0024] Preferably, an emergency stop button is also installed on the side of the control cabinet to ensure the safety of the operation experiment process.

[0025] This invention provides an experimental device for fire cyclones with independently adjustable generated vortex height and intensity. It can simulate fire cyclones under different generated vortex distribution conditions in nature. Through experimental simulation and theoretical analysis, it reveals the influence of generated vortices on the dynamic evolution law and mechanism of fire cyclones, providing a scientific basis for fire cyclone forecasting and early warning technology. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of a fire cyclone experimental device for independently adjusting the height and intensity of the generated vortex, provided in an embodiment of the present invention.

[0027] In the attached diagram: 1-Rotating gauze curtain; 2-Fireproof board; 3-Drive screw servo motor; 4-Guide rod servo motor; 5-Drive screw; 6-Gauze pressing sheet; 7-Emergency stop button; 8-Lifting control panel; 9-Rotating control panel; 10-Photoelectric sensor; 12-Drive wheel; 13-Slewing support bearing; 14-Reducer; 15-Drive wheel servo motor; 16-Guide rod; 17-Light-shielding element; 18-Control cabinet; 19-Driver. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0029] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0030] like Figure 1 The diagram shown illustrates the structure of a fire cyclone experimental apparatus for independently adjusting the height and intensity of a generated vortex, according to an embodiment of the present invention. The apparatus includes a control cabinet 18, a rotating screen 1, an experimental platform, a screen rotation system, and a platform lifting system. The rotating screen 1 is positioned at the top of the control cabinet 18. The experimental platform is located inside the rotating screen 1 and is used to place oil pans or burners of different sizes. The screen rotation system is mounted on the control cabinet 18 and is also connected to the rotating screen 1, driving the screen 1 to rotate when the system is in operation. The platform lifting system is located inside the control cabinet 18, with its top end connected to the experimental platform to ensure vertical lifting of the experimental platform.

[0031] The application provides a fire whirlwind experimental device with independently adjustable vortex height and intensity, which can simulate the fire whirlwind under different vortex distribution conditions in nature, and can reveal the influence of the vortex on the dynamic evolution rule and mechanism of the fire whirlwind through experimental simulation and theoretical analysis, thereby providing a scientific basis for the prediction and early warning technology of the fire whirlwind.

[0032] In one example of the application, the control cabinet 18 is fixed to the ground by a carbon steel heavy foot cup to ensure the stability of the device during operation, and cabinet doors are arranged on the front and rear sides of the control cabinet 18, which are made of transparent materials to facilitate observation of the internal operation, and a ventilation hole with a diameter of 5 cm is formed at the bottom end of the rear cabinet door to facilitate the passage of the gas pipeline.

[0033] As shown in Figure 1 As a preferred embodiment of the application, the experimental table top includes a steel plate and a fireproof plate 2.

[0034] The steel plate is fixedly installed on the inner side of the rotating gauze screen 1, and the fireproof plate 2 is connected with the steel plate through an inner hexagonal bolt.

[0035] A circular hole with a diameter of 50 cm is formed at the center of the steel plate and the fireproof plate 2, which is used to place oil pans or burners of different sizes to study the influence of fuel size.

[0036] In one example of the application, fine hair brushes are arranged on the side edges of the steel plate to reduce the interference of the lower airflow on the experimental flow field; the rotating gauze screen 1 has a diameter of 1 m and a height of 1.5 m, which is supported by four bent steel sheets with a width of 12 cm as support bodies, and 24-mesh stainless steel nets are arranged on the outer sides of the steel sheets, and the support bodies and the stainless steel nets are connected through a gauze pressing sheet 6 and a bolt; wherein the stainless steel nets ensure that the airflow freely enters during the experiment, the steel sheets serve as supports to ensure that the stainless steel nets form a circle, and the smaller the width of the steel sheets, the smaller the interference with the airflow.

[0037] As shown in Figure 1 As another preferred embodiment of the application, the gauze screen rotating system includes a driving wheel 12, a rotary support bearing 13, a speed reducer 14, and a driving wheel servo motor 15.

[0038] The rotary support bearing 13 is installed at the middle part of the top end of the control cabinet 18, and the rotary support bearing 13 is also connected with the rotating gauze screen 1 through a bolt.

[0039] The driving wheel 12, the speed reducer 14, and the driving wheel servo motor 15 are all arranged inside the control cabinet 18, and the driving wheel 12 is connected with the rotary support bearing 13.

[0040] The driving wheel servo motor 15 is electrically connected with a rotary control panel 9 arranged outside the control cabinet 18, the rotary control panel 9 can realize rotation of the rotating screen 1 in two directions of counterclockwise and clockwise, the rotating speed is adjusted through a knob arranged thereon, and the initial rotating speed can be set by human.

[0041] In an example of the present application, the driving wheel servo motor 15 drives the slewing bearing 13 and the rotating screen 1 to rotate around the oil pan or the burner through the reducer 14 and the driving wheel 12, and the slewing bearing 13 is adjusted in rotating speed and rotating direction through the rotary control panel 9 and the driver 19 sending a control signal to the driving wheel servo motor 15, the maximum rotating speed of the slewing bearing 13 is 70 rpm, the minimum increment is 1 rpm, and the greater the rotating speed is, the greater the additional circulation can be provided, so that how the flame evolves at high speed can be clearly seen.

[0042] As shown in Figure 1 As another preferred embodiment of the present application, the table lifting system comprises a driving screw servo motor 3, a guide rod servo motor 4, a driving screw 5 and a guide rod 16.

[0043] The driving screw 5 and the guide rod 16 are arranged in two, and the top ends of the driving screw 5 and the guide rod 16 are connected with the bottom of the experiment table.

[0044] The driving screw 5 is driven by the driving screw servo motor 3 arranged on the side to realize lifting of the experiment table, and the guide rod 16 is driven by the guide rod servo motor 4 arranged on the side to ensure vertical movement of the experiment table.

[0045] The driving screw servo motor 3 and the guide rod servo motor 4 are also electrically connected with a lifting control panel 8 arranged on the control cabinet 18, the lifting control panel 8 realizes lifting or lowering of the experiment table by controlling clockwise or counterclockwise rotation of the driving screw 5, and the lifting speed is adjusted through a knob arranged on the lifting control panel 8.

[0046] In an example of the present application, the diameter of the driving screw 5 is 2 cm, and the length is 120 cm, the length of the driving screw 5 determines the adjustable range of the generated vortex height, the diameter of the guide rod 16 is 3 cm, and the length is 120 cm; in use, the working state of the driving screw servo motor 3 and the guide rod servo motor 4 can be adjusted through the lifting control panel 8 to control the lifting height of the experiment table.

[0047] As shown in Figure 1 As another preferred embodiment of the present application, the bottom end of the guide rod 16 is provided with a light shielding element 17.

[0048] Two photoelectric sensors 10 are vertically arranged inside the control cabinet 18, and the two photoelectric sensors 10 are in the same line with the light shielding element 17.

[0049] In one example of the present application, when the light shielding element 17 at the bottom of the guide rod 16 passes the photoelectric sensor 10 at the bottom, the driving screw 5 starts to rise, and when the light shielding element 17 passes the photoelectric sensor 10 at the top, the movement stops at the end of the stroke; the lifting distance of the experiment table top can be adjusted through the lifting control panel 8 located at the side of the control cabinet 18, and the driving device 19 sends control signals to the driving screw servo motor 3 and the guide rod servo motor 4 to control the lifting speed, distance and direction of the experiment table top; when the keys on the lifting control panel 8 are operated, the driving screw 5 can be stopped at any position in the stroke, so as to achieve the purpose of stepless adjustment of the relative distance between the top of the rotating screen 1 and the experiment table top.

[0050] As shown in Figure 1 As another preferred embodiment of the present application, the side of the control cabinet 18 is also provided with an emergency stop button 7 to ensure the safety of the operation experiment.

[0051] In one example of the present application, the bottom of the control cabinet 18 is also provided with a driving device 19, which is electrically connected with the driving screw servo motor 3, the guide rod servo motor 4 and the driving wheel servo motor 15 to control the working process, and an overcurrent protection device is installed inside the driving device 19; wherein the emergency stop button 7, the lifting control panel 8, the rotating control panel 9 and the driving device 19 constitute a complete control system.

[0052] It is obvious to those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, and the scope of the present application is defined by the appended claims rather than the above description, and all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application.

[0053] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be properly combined to form other embodiments that those skilled in the art can understand.

Claims

1. A fire cyclone experimental device for independently adjusting the height and intensity of the generated vortex, comprising a control cabinet, characterized in that... Also includes: A rotating gauze curtain, which is positioned at the top of the control cabinet; An experimental work surface, located inside the rotating gauze curtain, is used to place oil pans or burners of different sizes; A gauze curtain rotation system is arranged on a control cabinet and is also connected to a rotating gauze curtain, driving the rotating gauze curtain to rotate when the gauze curtain rotation system is working. A table lifting system is installed inside the control cabinet, and the top of the table lifting system is connected to the experimental table to ensure that the experimental table can be raised and lowered vertically. The curtain rotation system includes a drive wheel, a slewing support bearing, a reducer, and a drive wheel servo motor; The slewing support bearing is installed at the top center of the control cabinet, and the slewing support bearing is also connected to the rotating screen by bolts; The drive wheel, reducer, and drive wheel servo motor are all installed inside the control cabinet. The drive wheel is connected to the slewing support bearing, and when the drive wheel servo motor is working, the reducer and drive wheel drive the slewing support bearing and the rotating screen to move around the oil pan or burner. The platform lifting system includes a drive screw servo motor, a guide rod servo motor, a drive screw, and a guide rod; Two drive screws and two guide rods are arranged, and the top ends of the drive screws and guide rods are connected to the bottom of the experimental platform. The drive screw is driven by a side-mounted drive screw servo motor to achieve the lifting and lowering of the experimental platform, and the guide rod is driven by a side-mounted guide rod servo motor to ensure the vertical movement of the experimental platform; The drive screw servo motor and guide rod servo motor are also electrically connected to the lifting control panel arranged on the control cabinet.

2. The experimental device for generating a fire cyclone with independently adjustable vortex height and intensity according to claim 1, characterized in that... The experimental platform includes a steel plate and a fireproof board; The steel plate is fixedly installed inside the rotating screen, and the fireproof board is connected to the steel plate by hex bolts. A circular hole with a diameter of 50cm is provided at the center of the steel plate and the fireproof plate.

3. The experimental apparatus for generating a fire cyclone with independently adjustable vortex height and intensity according to claim 1, characterized in that... The drive wheel servo motor is electrically connected to the rotary control panel located outside the control cabinet, and sends control signals to the drive wheel servo motor through the rotary control panel to adjust the speed and direction of the slewing support bearing.

4. The experimental apparatus for generating a fire cyclone with independently adjustable vortex height and intensity according to claim 1, characterized in that... A light-shielding element is installed at the bottom end of the guide rod; The control cabinet has two photoelectric sensors arranged vertically inside, and the two photoelectric sensors are aligned with the light-shielding element.

5. The experimental apparatus for generating a fire cyclone with independently adjustable vortex height and intensity according to claim 1, characterized in that... An emergency stop button is also installed on the side of the control cabinet to ensure the safety of the operation and experiment process.

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