A testing platform and method for effective smoke exhaust area of ​​natural smoke exhaust facilities

Abstract

The present invention discloses a testing platform and a testing method for an effective smoke exhaust area of ​​a natural smoke exhaust facility. The testing platform comprises a smoke generating device for generating smoke and testing the smoke exhaust efficiency of the natural smoke exhaust facility, an environmental wind simulation generating device for simulating an environmental wind field, and a controller connected to the two. The testing method comprises a testing method for a working condition without environmental wind and a working condition with environmental wind in two parts. The present invention can test the flow coefficient and the effective smoke exhaust area of ​​top-opening and side-opening natural smoke exhaust facilities under the influence of various fire source powers, various environmental wind speeds and wind direction angles in a more refined manner, greatly improving the rationality of the testing platform and the testing method and the accuracy of the test results, and effectively improving the defects of the existing testing technology that the testing environment is single and the influencing factors that can be simulated are limited, thus making it difficult to accurately reflect the real smoke exhaust environment of the natural smoke exhaust facility.

Description

Technical Field

[0001] The present invention relates to the technical field of fire detection equipment, and in particular to a testing platform and a testing method for the effective smoke exhaust area of ​​a natural smoke exhaust facility. Background Art

[0002] The efficient removal of smoke from a fire scene is crucial for the escape of personnel and fire rescue in the event of a fire. Natural smoke exhaust is widely used in a large number of construction projects as an economical and efficient smoke exhaust method. Natural smoke exhaust facilities such as natural smoke exhaust windows are the core components of natural smoke exhaust facilities. They are important bridges and media to help exhaust fire smoke to the outdoors. When designing natural smoke exhaust facilities, the determination of the effective smoke exhaust area of ​​each natural smoke exhaust facility should be as accurate as possible. Otherwise, the calculated total effective smoke exhaust area of ​​the system may not actually meet the design requirements, so that the natural smoke exhaust facility cannot have the necessary smoke exhaust capacity when a fire occurs, exacerbating casualties and property losses.

[0003] At present, my country and Japan mainly use a simple calculation method, that is, by calculating the projection area of ​​the facility's open fan blades in the horizontal or vertical direction or the cross-sectional area of ​​the effective flow path when the smoke flows through the facility's holes to determine the effective smoke exhaust area. This method is difficult to equivalently reflect the difference in geometric characteristics such as the length-to-width ratio of the facility's holes and the direction of the fan blades opening in the size of the effective smoke exhaust area, and it is completely unable to reflect the impact of indoor fire smoke characteristics and outdoor environmental wind field characteristics on the smoke exhaust efficiency of natural smoke exhaust facilities. European and American countries mainly use aerodynamic effective area as an indicator, that is, based on the principle of aerodynamics, the product of the flow coefficient of the natural smoke exhaust facility and the area of ​​the facility's holes is used as the effective smoke exhaust area. This method can reflect the impact of various factors on the effective smoke exhaust area in the flow coefficient indicator under the same benchmark, which is a more scientific and reasonable determination method. Whether the determination of the effective smoke exhaust area is accurate depends on whether the determination of the flow coefficient of the natural smoke exhaust facility is reasonable and accurate.

[0004] At present, the relevant standards and specifications in the United States do not provide specific test platforms and test methods for the flow coefficient of natural smoke exhaust facilities, except that the recommended values ​​provided by the manufacturer or standards can be referred to. Although Australia has formulated the test standard AS 2428.5-2004 (R2016), the test platform specified in the standard does not introduce an environmental wind field simulation device, and it is impossible to test the smoke exhaust efficiency of natural smoke exhaust facilities under the influence of the environmental wind field. In addition, the natural smoke exhaust facility to be tested is installed at the end of a slender wind tunnel test platform with a fixed position, which cannot reflect the difference in smoke exhaust efficiency of natural smoke exhaust facilities caused by different installation positions (such as top opening or side opening) under the same fire environment. At present, the test platform and test methods specified in the European standard EN12101-2:2017 represent the international leading level and are relatively complete, but there are still many areas that need to be optimized and improved. First, although the test platform includes an environmental wind field simulation device, the test method only requires the test platform to provide a wind field environment with a wind speed value of not less than 10m / s for ambient wind conditions, so it is impossible to examine the smoke exhaust efficiency of natural smoke exhaust facilities under various ambient wind speed conditions. Secondly, although the test method takes into account the difference in smoke exhaust efficiency between top-opening and side-opening natural smoke exhaust facilities, it only focuses on the top-opening type in terms of the impact of ambient wind. It stipulates that the top-opening natural smoke exhaust facilities must be tested and calculated under conditions without ambient wind and conditions with ambient wind, respectively, while the side-opening type only needs to be tested and calculated under conditions without ambient wind. In addition, regardless of the top-opening or side-opening type, the installation position of the natural smoke exhaust facilities in the test platform is at the top of the test cavity, and the difference between the two is not reflected in the geometric structure of the test platform. Finally, whether it is the above-mentioned European standard or the aforementioned Australian standard, in the test platform specified in the standard, the gas flowing through the natural smoke exhaust facilities is normal temperature air driven by the mechanical power of the fan. This is different from the flow field characteristics of the high-temperature smoke in the actual fire scene that naturally rises under the drive of buoyancy and flows through the natural smoke exhaust facilities. It is difficult to truly reflect the smoke characteristics of the actual fire scene.

[0005] In summary, among the mature technologies currently available at home and abroad, there is no testing platform and testing method for the effective smoke exhaust area of ​​natural smoke exhaust facilities that fully examines the impact of three factors, namely the installation location of natural smoke exhaust facilities, indoor fire smoke characteristics, and outdoor environmental wind field characteristics, on the smoke exhaust efficiency of natural smoke exhaust facilities. Summary of the invention

[0006] In view of the defects of existing natural smoke exhaust facility effective smoke exhaust area testing technology, such as single testing environment and limited simulatable influencing factors, which makes it difficult to accurately reflect the actual smoke exhaust environment of the natural smoke exhaust facility and leads to poor testing accuracy, the present invention discloses a natural smoke exhaust facility effective smoke exhaust area testing platform and testing method, which can more finely test the flow coefficient and effective smoke exhaust area of ​​top-opening and side-opening natural smoke exhaust facilities under the influence of various fire source powers, various environmental wind speeds and wind directions, thereby greatly improving the rationality of the testing platform and the testing method and the accuracy of the test results.

[0007] A test platform for the effective smoke exhaust area of ​​a natural smoke exhaust facility, characterized by comprising a smoke generating device for generating smoke and testing the smoke exhaust efficiency of the natural smoke exhaust facility, an environmental wind simulation generating device for simulating an environmental wind field, and controllers respectively connected to the two.

[0008] Preferably, the smoke generating device includes a rotating mounting table, a smoke collecting hood, a smoke storage static pressure chamber, and a first test device, a second test device and a third test device respectively used to collect smoke mass flow, temperature and pressure difference.

[0009] Preferably, the top of the smoke collecting hood is connected to the smoke storage static pressure chamber through a drainage duct, and the top surface and any side surface of the smoke storage static pressure chamber are provided with installation ports for installing the natural smoke exhaust facility to be tested; the first test device is arranged in the drainage duct, and the second test device and the third test device are arranged in the smoke storage static pressure chamber, and the first test device, the second test device and the third test device are respectively connected to the controller.

[0010] Preferably, there are 2-6 drainage tubes in total, and they are evenly arranged along the circular trajectory; a flow equalizing grid is also fixedly installed in the drainage tube; as needed, some of the drainage tubes are also controlled by setting a quick-release plug to control their on and off states, and the drainage tubes equipped with the quick-release plugs are centrally symmetrically arranged about the center of the circular trajectory.

[0011] Preferably, a guide plate is provided in the smoke storage static pressure chamber, and the guide plate is arranged opposite to the drainage pipe; a plurality of electric push rods for controlling the position of the guide plate are also provided in the smoke storage static pressure chamber, and the electric push rods are connected to the controller.

[0012] Preferably, the environmental wind simulation generating device includes a scissor-type lifting platform, a variable frequency fan and an air uniform cavity, and the variable frequency fan and the air uniform cavity are both fixed on the scissor-type lifting platform; the variable frequency fan is connected to the controller, and its air outlet is connected to the air uniform cavity; the air uniform cavity is also provided with a flow equalizing grille and an air supply outlet.

[0013] Preferably, the controller includes a data collector, a control cabinet and a PC terminal, the input end of the data collector is connected to the first test device, the second test device and the third test device respectively through the RS485 bus, and the output end is connected to the PC terminal through the RS485 bus, and the PC terminal is connected to the control cabinet.

[0014] Correspondingly, the present invention also discloses a testing method for a testing platform for an effective smoke exhaust area of ​​a natural smoke exhaust facility, which is characterized in that: the natural smoke exhaust facility to be tested needs to be tested in a condition without ambient wind and in a condition with ambient wind in sequence.

[0015] Preferably, the no-ambient wind condition test comprises the following steps:

[0016] S1. Calibrate the first test device, the second test device, the third test device and the variable frequency fan, and perform communication debugging on the controller, the ambient wind simulation generating device and each test device;

[0017] S2. Install the natural smoke exhaust facility to be tested at the corresponding installation port according to the actual working conditions of the natural smoke exhaust facility to be tested; adjust the height of the guide plate to ensure that a uniform smoke flow field environment can be formed in the smoke storage static pressure chamber;

[0018] S3. Add the corresponding fuel to the combustion disk according to the flue gas power and test duration required for the test, and determine whether to install a quick-release plug according to actual needs to block part of the drainage pipe to ensure that the flue gas entering the smoke storage static pressure chamber has sufficient power and flow rate;

[0019] S4, ignite the fuel, and test various parameters by the first test device, the second test device, and the third test device until the fire source is extinguished;

[0020] S5. Based on the sum of the smoke mass flow rate m of each drainage pipe, the average absolute temperature T of each temperature measuring point, the average pressure difference Δp of each pressure measuring point, and the geometric opening area A of the natural smoke exhaust facility to be tested v Calculate the flow coefficient value C of the natural smoke exhaust facility to be tested v , and its calculation formula is as follows:

[0021] S6. Calculate the effective smoke exhaust area A of the natural smoke exhaust facility to be tested according to the flow coefficient value calculated in step S5. e , the calculation formula is: e =A v ·C v .

[0022] Preferably, the ambient wind condition test includes, in addition to the above steps S1 to S6, the following steps between steps S2 and S3:

[0023] A1. By rotating the rotating mounting platform, the air supply direction of the air supply port of the air distribution cavity acts on the wind direction angle of the natural smoke exhaust facility to be tested to meet the design requirements;

[0024] A2. Adjust the height of the scissor lift and its relative position to the natural smoke exhaust facility to be tested, so that the projection of the air outlet of the air distribution cavity along the air supply direction completely covers the projection of the natural smoke exhaust facility to be tested in that direction;

[0025] A3. Start the variable frequency fan, adjust the air volume of the variable frequency fan and the distance between the air outlet of the air balancing cavity and the natural smoke exhaust facility to be tested, so that the wind speed acting at the center point of the geometric opening of the natural smoke exhaust facility to be tested reaches the design value and remains stable.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. The top surface and any side surface of the smoke storage static pressure chamber of the present invention are provided with installation ports for installing the natural smoke exhaust facilities to be tested, so that natural smoke exhaust facilities with different installation forms can be tested as needed, and the smoke exhaust form of the natural smoke exhaust facilities is highly restored, thereby improving the disadvantage that the natural smoke exhaust facilities to be tested in the existing test platform can only be fixedly installed at the end of the wind tunnel or the top of the test cavity, and the difference in smoke exhaust efficiency between the smoke exhaust skylight and the smoke exhaust side window cannot be reflected.

[0028] 2. The test platform of the present invention is provided with a real fire source. During the test, the gas flowing through the natural smoke exhaust facility is high-temperature smoke that naturally rises under the driving force of buoyancy. This improves the disadvantage that the existing test platform only uses normal-temperature air driven by a fan instead of high-temperature smoke, thereby failing to reflect the real flow field characteristics around the natural smoke exhaust facility in a fire environment.

[0029] 3. The testing method of the present invention requires that both side-opening and top-opening natural smoke exhaust facilities to be tested must be tested under conditions with and without ambient wind, which improves the existing testing methods or the testing requirements without ambient wind conditions or only requires top-opening natural smoke exhaust facilities to be tested under ambient wind conditions, thereby failing to comprehensively examine the smoke exhaust efficiency of the natural smoke exhaust facilities to be tested.

[0030] 4. The test platform of the present invention can adjust the height of the scissor lift platform and its relative position to the natural smoke exhaust facility to be tested, so that the natural smoke exhaust facility to be tested, whether side-opening or top-opening, can be within the wind field coverage of the ambient wind simulation generating device, thereby ensuring the consistency of the ambient wind field of each test condition and improving the accuracy of the test results under ambient wind conditions.

[0031] 5. The test platform of the present invention can adjust the air volume of the variable frequency fan and the distance between the air outlet of the wind equalizing cavity and the natural smoke exhaust facility to be tested, so that the wind field output by the air outlet of the wind equalizing cavity can achieve various required environmental wind speeds at the center point of the geometric opening of the natural smoke exhaust facility to be tested, thereby truly restoring the various wind speeds faced by the natural smoke exhaust facility to be tested at different installation locations and different elevations. This improves the disadvantage that the existing test platform can only provide a single wind speed value and cannot fully examine the impact of the actual wind field environment.

[0032] 6. The present invention provides 2 to 6 drainage tubes in total, which are evenly arranged along the circular trajectory. According to needs, several groups of drainage tubes symmetrically arranged around the center point of the circular trajectory can be blocked by quick-release plugs to control their on and off states. This can ensure the uniformity of the smoke flow field in the smoke storage static pressure chamber at all times, and solve the problem that in some test conditions, the smoke flow in the drainage tube is too small due to insufficient rising power of the smoke, making it impossible to accurately collect relevant parameters.

[0033] 7. The smoke storage static pressure chamber of the present invention is also provided with a guide plate and an electric push rod connected to the controller. The height of the guide plate can be adjusted in a targeted manner by the electric push rod according to the different installation locations of the natural smoke exhaust facilities of the target to be tested, thereby making the smoke flow field in the smoke storage static pressure chamber more uniform, making the parameters read at each measuring point more representative, and greatly improving the accuracy of the test.

[0034] 8. The testing method of the present invention determines the smoke mass flow rate flowing through the natural smoke exhaust facility to be tested by indirectly measuring the smoke mass flow rate in each drainage pipe. It uses the principle of conservation of mass to cleverly solve the problem that the smoke flow field of the natural smoke exhaust facility opening that naturally rises under the drive of buoyancy is relatively turbulent and the flow velocity is relatively low, making it difficult to directly and accurately collect the smoke mass flow rate flowing through the entire opening cross-section. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the structure of the present invention;

[0036] Figure 2 This is a schematic diagram of the cross-sectional structure of the present invention along line AA

[0037] Figure 3 This is a flow chart of the testing method under the condition of no ambient wind of the present invention;

[0038] Figure 4 This is a flow chart of the testing method under ambient wind conditions of the present invention;

[0039] Figure numerals: 1. Smoke generating device, 2. Environmental wind simulation generating device, 3. Controller, 11. Rotating mounting table, 12. Smoke collecting hood, 13. Smoke storage static pressure chamber, 14. First test device, 15. Second test device, 16. Third test device, 17. Drainage pipe, 18. Mounting port, 19. Flow equalizing grille, 21. Scissor lift table, 22. Frequency conversion fan, 23. Wind equalizing cavity, 24. Air supply port, 31. Data collector, 32. Control cabinet, 33. PC terminal, 131. Guide plate, 132. Electric push rod, 171. Quick-release plug. DETAILED DESCRIPTION

[0040] The present invention will be further described below through specific embodiments:

[0041] Implementation Method 1

[0042] This embodiment is a basic embodiment of the present invention, which discloses a natural smoke exhaust facility effective smoke exhaust area test platform, and its specific structure is as follows: Figure 1 to Figure 2 As shown, it includes a controller 3, a smoke generating device 1 and an environmental wind simulation generating device 2, wherein the smoke generating device 1 includes a smoke storage static pressure chamber 13, a drainage pipe 17, a smoke collecting hood 12 and a rotating mounting platform 11, the top and any side of the smoke storage static pressure chamber 13 are provided with a mounting port 18 for installing the natural smoke exhaust facility to be tested, the bottom of the smoke storage static pressure chamber 13 is connected to the top of the smoke collecting hood 12 through the drainage pipe 17, so that the smoke storage static pressure chamber 13 and the smoke collecting hood 12 are connected to each other; the smoke collecting hood 12 is in the shape of a cone, a square cone or other shape suitable for collecting and storing smoke, and its four corners are fixedly connected to the rotating mounting platform 11 through connecting columns; a combustion disk for carrying a simulated fire source is also placed on the rotating mounting platform 11, and the combustion disk is arranged opposite to the center of the smoke collecting hood 12; at the same time, the rotating mounting platform 11 can be rotated manually by using a universal wheel, or can be driven to rotate by a stepping motor, so as to indirectly adjust the wind direction angle of the air supply of the environmental wind simulation generating device 2 acting on the natural smoke exhaust facility to be tested.

[0043] At the same time, according to the needs of actual working conditions, the drainage pipes 17 are provided with 2-6 in total, with 4 being the best. All the drainage pipes 17 are symmetrically arranged between the smoke storage static pressure chamber 13 and the smoke collection hood 12 in a circular installation trajectory with the center of the smoke collection hood 12 as the center of the circle; a first test device 14 is fixedly provided in the middle of the drainage pipe 17, and the first test device 14 adopts a mass flow meter to realize the collection of the smoke mass flow parameter, which is installed at the center of the cross section of the drainage pipe 17; at the same time, a flow equalizing grid 19 is also fixedly provided at the lower part of the first test device 14;

[0044] According to the test requirements, determine whether it is necessary to set a quick-release plug 171 at the smoke inlet end of the partial drainage pipe 17, so as to adjust the smoke mass flow rate between the smoke storage static pressure chamber 13 and the smoke hood 12 by blocking the drainage pipe 17; the drainage pipe 17 equipped with the quick-release plug 171 needs to be symmetrically arranged with the center of the smoke hood 12 as the symmetry point;

[0045] The top of the smoke storage static pressure chamber 13 is provided with a plurality of second test devices 15 and a plurality of third test devices 16, wherein the second test device 15 is a temperature sensor for collecting temperature parameters in the smoke storage static pressure chamber 13. According to needs, a total of 4 second test devices 15 are provided, which are fixedly arranged at the four corners of the upper middle part of the smoke storage static pressure chamber 13; the third test device 16 is a pressure difference sensor for testing the pressure difference between the smoke storage static pressure chamber 13 and the external atmosphere. The number of the third test devices 16 is the same as the number of the side walls of the smoke storage static pressure chamber 13, and they are distributed in the upper middle part of each side wall of the smoke storage static pressure chamber 13 and fixed on the side wall; thereby ensuring the accuracy and representativeness of the collected data;

[0046] At the same time, a guide plate 131 is also arranged in the middle and lower part of the smoke storage static pressure chamber 13, and the guide plate 131 is opposite to each drainage tube 17, and its projection in the axial direction of the drainage tube 17 completely covers all the drainage tubes 17; the guide plate 131 is not in contact with the inner walls of the smoke storage static pressure chamber 13 on all sides, so as to ensure that a corresponding gap is left between the edge of the guide plate 131 and the inner walls of the smoke storage static pressure chamber 13 for smoke to flow, and an electric push rod 132 is also arranged at the bottom of the smoke storage static pressure chamber 13, and the electric push rod 132 is connected to the guide plate 131, so that the position of the guide plate 131 is changed by the electric push rod 132; a corresponding distance sensor is also arranged in the smoke storage static pressure chamber 13 to detect the height of the guide plate; the distance sensor is connected to the controller 3.

[0047] The environmental wind simulation generating device 2 includes a scissor-type lifting platform 21, a variable frequency fan 22 and an air distribution cavity 23, wherein the variable frequency fan 22 and the air distribution cavity 23 are both fixed on the scissor-type lifting platform 21, the air outlet of the variable frequency fan 22 is connected to the air inlet at the bottom of the air distribution cavity 23, and an air supply port 24 is also provided on the upper side of the air distribution cavity 23, and a flow distribution grid 19 is provided inside the air distribution cavity 23;

[0048] The controller 3 includes a data collector 31, a PC terminal 33 and a control cabinet 32, wherein the PC terminal 33 is connected to the data collector 31 and the control cabinet 32 ​​via an RS485 bus, the control cabinet 32 ​​is connected to the variable frequency fan 22 via a frequency converter, and a regulator matching the electric push rod 132 is also provided on the control cabinet 32; the signal input end of the data collector 31 is connected to the first detection device 14, the second detection device 15 and the third detection device 16 via RS485, and the electric push rod 132 is connected to the PC terminal 33 via the control cabinet.

[0049] This embodiment, as another embodiment of the present invention, discloses a method for testing an effective smoke exhaust area test platform of a natural smoke exhaust facility under no ambient wind conditions, which comprises the following steps:

[0050] S1. Calibrate the first test device, the second test device, the third test device and the variable frequency fan, and perform communication debugging on the controller, the ambient wind simulation generating device and each test device to ensure the stability of data reading and transmission during the test;

[0051] S2. Install the natural smoke exhaust facility to be tested at the corresponding installation opening of the smoke plenum chamber according to the actual working condition of the natural smoke exhaust facility to be tested. For example, if the natural smoke exhaust facility to be tested is installed on the top of a building in the actual working condition, it is fixed to the installation opening on the top of the smoke plenum chamber during installation, and the installation opening on the side of the smoke plenum chamber is sealed; when the natural smoke exhaust facility to be tested is installed on the side wall of a building in the actual working condition, it is correspondingly installed at the installation opening on the side of the smoke plenum chamber, and the installation opening on the top is sealed; after installation, the height of the guide plate is adjusted to the required height for the test by an electric push rod to ensure that a uniform smoke flow field environment can be formed in the smoke plenum chamber;

[0052] S3. Add corresponding fuel to the combustion disk according to the fire source power value and test duration determined before the test. When the fire source power value is small, it can be determined whether to install a quick-release plug according to actual needs to block part of the drainage pipes to ensure that the smoke entering the smoke storage static pressure chamber has sufficient power and flow rate; the blocked drainage pipes are symmetrically distributed with the center of the circular installation trajectory of each drainage pipe as the center point;

[0053] S4, ignite the fuel, and test various parameters by the first test device, the second test device, and the third test device until the fire source is extinguished;

[0054] S5. Add the test data of each first test device to obtain the sum of the smoke mass flow rate m, calculate the absolute temperature average value T according to the data obtained by each second test device, and calculate the pressure difference average value Δp according to the data obtained by each third test device; at the same time, calculate the geometric opening area A of the natural smoke exhaust facility to be tested according to its structure. v , and the flow coefficient value C of the natural smoke exhaust facility to be tested is obtained according to the following formula v ,in

[0055] S6. Calculate the effective smoke exhaust area A of the natural smoke exhaust facility to be tested according to the flow coefficient value calculated in step S5. e , the calculation formula is: e =A v ·C v .

[0056] Implementation 3

[0057] This embodiment, as another embodiment of the present invention, discloses a method for testing an effective smoke exhaust area test platform of a natural smoke exhaust facility under ambient wind conditions, which comprises the following steps:

[0058] S1. Calibrate the first test device, the second test device, the third test device and the variable frequency fan, and perform communication debugging on the controller, the ambient wind simulation generating device and each test device to ensure the stability of data reading and transmission during the test;

[0059] S2. Install the natural smoke exhaust facility to be tested at the corresponding installation opening of the smoke plenum chamber according to the actual working condition of the natural smoke exhaust facility to be tested. For example, if the natural smoke exhaust facility to be tested is installed on the top of a building in the actual working condition, it is fixed to the installation opening on the top of the smoke plenum chamber during installation, and the installation opening on the side of the smoke plenum chamber is sealed; when the natural smoke exhaust facility to be tested is installed on the side wall of a building in the actual working condition, it is correspondingly installed at the installation opening on the side of the smoke plenum chamber, and the installation opening on the top is sealed; after installation, the height of the guide plate is adjusted to the required height for the test by an electric push rod to ensure that a uniform smoke flow field environment can be formed in the smoke plenum chamber;

[0060] S3. Determine in advance the reference position of the natural smoke exhaust facility to be tested relative to the direction of the air outlet of the air distribution cavity, and rotate the rotating mounting table so that the air supply direction of the air outlet of the air distribution cavity acts on the wind direction angle of the natural smoke exhaust facility to be tested to meet the design requirements;

[0061] S4. Adjust the height of the scissor lift platform and its relative position to the natural smoke exhaust facility to be tested, so that the projection of the air supply outlet of the wind-distributing cavity along the air supply direction completely covers the projection of the natural smoke exhaust facility to be tested in this direction; S5. Start the variable frequency fan, adjust the air volume of the variable frequency fan and the distance between the air supply outlet of the wind-distributing cavity and the natural smoke exhaust facility to be tested, so that the wind speed acting at the center point of the geometric opening of the natural smoke exhaust facility to be tested reaches the design value and remains stable.

[0062] S6. Add corresponding fuel to the combustion disk according to the fire source power value and test duration determined before the test. When the fire source power value is small, it can be determined whether to install a quick-release plug according to actual needs to block part of the drainage pipes to ensure that the smoke entering the smoke static pressure chamber has sufficient power and flow rate; the blocked drainage pipes are symmetrically distributed with the center of the circular installation trajectory of each drainage pipe as the center point;

[0063] S7, ignite the fuel, and test various parameters using the first test device, the second test device, and the third test device until the fire source is extinguished;

[0064] S8. Add the test data of each first test device to obtain the sum of the smoke mass flow rate m, calculate the absolute temperature average value T based on the data obtained by each second test device, and calculate the pressure difference average value Δp based on the data obtained by each third test device; at the same time, calculate the geometric opening area A of the natural smoke exhaust facility to be tested based on its structure. v , and the flow coefficient value C of the natural smoke exhaust facility to be tested is obtained according to the following formula v ,in

[0065] S9. Calculate the effective smoke exhaust area A of the natural smoke exhaust facility to be tested according to the flow coefficient value calculated in step S5. e , the calculation formula is: e =A v ·C v .

[0066] The present invention discloses a test platform for the effective smoke exhaust area of ​​a natural smoke exhaust facility and a test method thereof. The test platform includes a smoke generating device for generating smoke and testing the smoke exhaust efficiency of the natural smoke exhaust facility, an environmental wind simulation generating device for simulating an environmental wind field, and a controller connected to both. The test method includes a test method for a condition without environmental wind and a test method for a condition with environmental wind. The present invention incorporates the influence of three factors, namely, the installation position of the natural smoke exhaust facility, the smoke characteristics of the indoor fire scene, and the characteristics of the outdoor environmental wind field, on the smoke exhaust efficiency of the natural smoke exhaust facility to be tested into the design of the test platform and the test method, and can more finely test the flow coefficient and effective smoke exhaust area of ​​top-opening and side-opening natural smoke exhaust facilities under the influence of various fire source powers, various environmental wind speeds, and wind direction angles, greatly improving the rationality of the test platform and the test method and the accuracy of the test results, and effectively improving the defects of the existing test technology that the test environment is single and the influencing factors that can be simulated are limited, thus making it difficult to accurately reflect the real smoke exhaust environment of the natural smoke exhaust facility.

Claims

1. A method for testing a natural smoke exhaust facility effective smoke exhaust area test platform, characterized in that: The natural smoke exhaust facility effective smoke exhaust area test platform comprises a smoke generating device (1) for generating smoke and testing the smoke exhaust efficiency of the natural smoke exhaust facility, an environmental wind simulation generating device (2) for simulating an environmental wind field, and a controller (3) respectively connected to the two. The smoke generating device (1) comprises a rotating mounting platform (11), a smoke collecting hood (12), a smoke storage static pressure chamber (13) which are connected to each other, and a first testing device (14), a second testing device (15) and a third testing device (16) which are respectively used to collect smoke mass flow, temperature and air pressure difference; The top of the smoke collecting hood (12) is connected to the smoke storage static pressure chamber (13) through a drainage pipe (17), and the top surface and any side surface of the smoke storage static pressure chamber (13) are provided with an installation opening (18) for installing the natural smoke exhaust facility to be tested; A total of 2 to 6 drainage tubes (17) are provided, and they are evenly arranged along the annular track; some of the drainage tubes (17) are also provided with quick-release plugs (171) to control their on and off states, and the drainage tubes (17) provided with the quick-release plugs (171) are centrally symmetrically arranged about the center of the annular track; A guide plate (131) is arranged in the smoke storage static pressure chamber (13), and the guide plate (131) is arranged directly opposite to the drainage pipe (17); The environmental wind simulation generating device (2) comprises a scissor-type lifting platform (21), a variable frequency fan (22) and an air distribution cavity (23), wherein the variable frequency fan (22) and the air distribution cavity (23) are both fixed on the scissor-type lifting platform (21); the variable frequency fan (22) is connected to the controller (3), and its air outlet is connected to the air distribution cavity (23); The test method is to conduct a no-ambient wind working condition test and an ambient wind working condition test on the natural smoke exhaust facility to be tested, wherein the no-ambient wind working condition test includes the following steps: S1. Calibrate the first test device, the second test device, the third test device and the variable frequency fan, and perform communication debugging on the controller, the ambient wind simulation generating device and the first test device, the second test device and the third test device; S2. Install the natural smoke exhaust facility to be tested at the corresponding installation port according to the actual working conditions of the natural smoke exhaust facility to be tested; adjust the height of the guide plate to ensure that a uniform smoke flow field environment can be formed in the smoke storage static pressure chamber; S3. Add the corresponding fuel to the combustion disk according to the flue gas power and test duration required for the test, and determine whether to install a quick-release plug according to actual needs to block part of the drainage pipe to ensure that the flue gas entering the smoke storage static pressure chamber has sufficient power and flow rate; S4, ignite the fuel, and test various parameters by the first test device, the second test device, and the third test device until the fire source is extinguished; S5. Based on the sum of the smoke mass flow rate m of each drainage pipe, the average absolute temperature T of each temperature measuring point, the average pressure difference Δp of each pressure measuring point, and the geometric opening area A of the natural smoke exhaust facility to be tested v Calculate the flow coefficient value C of the natural smoke exhaust facility to be tested v , and its calculation formula is as follows: S6. Calculate the effective smoke exhaust area A of the natural smoke exhaust facility to be tested according to the flow coefficient value calculated in step S5. e , the calculation formula is: e =A v ·C v .

2. The testing method of the effective smoke exhaust area testing platform of a natural smoke exhaust facility according to claim 1 is characterized in that: The first test device (14) is arranged in the drainage pipe (17), the second test device (15) and the third test device (16) are arranged in the smoke storage static pressure chamber (13), and the first test device (14), the second test device (15) and the third test device (16) are respectively connected to the controller (3).

3. The testing method of the effective smoke exhaust area testing platform of a natural smoke exhaust facility according to claim 2 is characterized in that: A flow equalizing grid (19) is also fixedly arranged in the drainage pipe (17).

4. The testing method of the effective smoke exhaust area testing platform of a natural smoke exhaust facility according to claim 1 is characterized in that: A plurality of electric push rods (132) for controlling the position of the guide plate (131) are also arranged in the smoke storage static pressure chamber (13), and the electric push rods (132) are connected to the controller (3).

5. The testing method of the effective smoke exhaust area testing platform of a natural smoke exhaust facility according to claim 1 is characterized in that: The air distribution cavity (23) is provided with a flow distribution grid (19) and an air supply port (24).

6. The method for testing the effective smoke exhaust area test platform of a natural smoke exhaust facility according to claim 1, characterized in that: The controller (3) comprises a data collector (31), a control cabinet (32) and a PC terminal (33); the input end of the data collector (31) is respectively connected to the first test device (14), the second test device (15) and the third test device (16) via an RS485 bus, and the output end is connected to the PC terminal (33) via an RS485 bus; the PC terminal (33) is connected to the control cabinet (32).

7. The method for testing the effective smoke exhaust area test platform of a natural smoke exhaust facility according to claim 1, characterized in that: The ambient wind condition test includes steps S1 to S6 as described in claim 1, and further includes the following steps between step S2 and step S3: A1. By rotating the rotating mounting platform, the air supply direction of the air supply port of the air distribution cavity acts on the wind direction angle of the natural smoke exhaust facility to be tested to meet the design requirements; A2. Adjust the height of the scissor lift and its relative position to the natural smoke exhaust facility to be tested, so that the projection of the air outlet of the air distribution cavity along the air supply direction completely covers the projection of the natural smoke exhaust facility to be tested in that direction; A3. Start the variable frequency fan, adjust the air volume of the variable frequency fan and the distance between the air outlet of the air balancing cavity and the natural smoke exhaust facility to be tested, so that the wind speed acting at the center point of the geometric opening of the natural smoke exhaust facility to be tested reaches the design value and remains stable.

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