Fire extinguishing agent quality compensation testing device and method for total flooding gas fire extinguishing protection area

Abstract

The application discloses a kind of fire extinguishing agent mass compensation test device and method of full submergence gas fire extinguishing protection zone, belong to fire safety technical field.The device includes protection zone model, air-tightness adjustment and test system, global heating and spray linkage system, data monitoring system and control terminal.The method is actively constructed multiple quantitative air-tightness conditions in protection zone model by control terminal, executes standard fire extinguishing agent spray test under each condition, and estimates fire extinguishing agent mass compensation amount using data monitoring result;Finally, empirical model between air leakage rate parameter and fire extinguishing agent mass compensation amount is fitted and established.The application discloses a kind of fire extinguishing agent mass compensation test device and method of full submergence gas fire extinguishing protection zone, belong to fire safety technical field.The device includes protection zone model, air-tightness adjustment and test system, global heating and spray linkage system, data monitoring system and control terminal.The method is actively constructed multiple quantitative air-tightness conditions in protection zone model by control terminal, executes standard fire extinguishing agent spray test under each condition, and estimates fire extinguishing agent mass compensation amount using data monitoring result;Finally, empirical model between air leakage rate parameter and fire extinguishing agent mass compensation amount is fitted and established.The application discloses a kind of fire extinguishing agent mass compensation test device and method of full submergence gas fire extinguishing protection zone, belong to fire safety technical field.The device includes protection zone model, air-tightness adjustment and test system, global heating and spray linkage system, data monitoring system and control terminal.The method is actively constructed multiple quantitative air-tightness conditions in protection zone model by control terminal, executes standard fire extinguishing agent spray test under each condition, and estimates fire extinguishing agent mass compensation amount using data monitoring result;Finally, empirical model between air leakage rate parameter and fire extinguishing agent mass compensation amount is fitted and established.The application discloses a kind of fire extinguishing agent mass compensation test device and method of full submergence gas fire extinguishing protection zone, belong to fire safety technical field.The device includes protection zone model, air-tightness adjustment and test system, global heating and spray linkage system, data monitoring system and control terminal.The method is actively constructed multiple quantitative air-tightness conditions in protection zone model by control terminal, executes standard fire extinguishing agent spray test under

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of fire safety, and particularly relates to a testing device and method for evaluating and improving the long-term reliability of a total flooding gas fire extinguishing system, and more particularly to a device and method for determining the quality compensation amount of fire extinguishing agent through simulation testing. BACKGROUND

[0002] A total flooding gas fire extinguishing system releases a certain amount of gas fire extinguishing agent into a closed protected area, so that the fire extinguishing agent is uniformly distributed in the protected area and is required to be maintained at a certain concentration range (which refers to the interval from the design fire extinguishing concentration to the minimum fire extinguishing concentration) for a specified period of time (soaking time, usually 10 minutes according to domestic and foreign standards, in order to distinguish from the term "maintenance time", hereinafter referred to as "maintenance time", which refers to the time required to completely extinguish a fire), thereby achieving the purpose of extinguishing a fire. Due to its high fire extinguishing efficiency and small secondary damage to the protected object, this system is widely used in high-value or important places such as data centers, archives, museums, and ship cabins. The effectiveness of this system is based on the fact that the fire extinguishing agent can reach the design fire extinguishing concentration and maintain not less than the minimum fire extinguishing concentration in the entire protected space after release, which highly depends on the air tightness of the enclosure structure and the interior of the protected area. However, the protected area in reality is not absolutely sealed, and the building structure will age and deform over time, the sealing materials at the air ducts of the ventilation and air conditioning system and the cable wall holes will also degrade in performance, and in addition, small damages that may not be noticed during routine maintenance will all cause the overall air tightness of the protected area to deteriorate irreversibly year by year. This slow increase in air leakage rate may cause the fire extinguishing agent concentration to drop below the minimum fire extinguishing concentration too early when a fire occurs, resulting in failure to extinguish the fire or a high risk of rekindling, which constitutes a hidden but critical risk point for the total flooding gas fire extinguishing system in long-term operation.

[0003] In view of the influence of the air tightness of the protected area on the fire extinguishing effect, the industry has carried out research and formed some evaluation methods. One commonly used method is the air tightness detection technology based on fan pressurization or depressurization (fan test or fan door test), which artificially establishes positive or negative pressure in the protected area by installing a calibrated fan on the door of the protected area, measures the air flow under different pressure differences, and calculates the air changes (air leakage rate) or equivalent leakage area of the protected area under a certain pressure (such as 50 Pa of base pressure difference according to GB / T34010). The core purpose of this method is to evaluate the current physical sealing state of the protected area, and the test results are often used to guide the search and plugging of leakage points to ensure that the protected area can meet the design assumed air tightness basis after system installation or overhaul. However, this method can only give the current quantitative characteristics of the air leakage of the protected area.

[0004] In order to more accurately predict the hold time of the extinguishing agent in a specific protection zone (the time period from when the extinguishing agent completes the spraying action to when the protection height drops from the design concentration to the minimum extinguishing concentration due to the leakage of the protection zone), based on the quantified characteristics of the leakage condition of the fan test, more in-depth model research has emerged. For example, US5128881A discloses a device and method for predicting the hold time in a protection zone equipped with a total flooding extinguishing system. This technology studies the influence of different leakage conditions on the concentration decay of the extinguishing agent by setting adjustable simulated leakage holes on the experimental cabin and actually spraying extinguishing agents such as halon. It establishes a simplified model that takes into account the non-linear characteristics of extinguishing agent leakage flow (power relationship between flow and pressure difference), indoor gas mixing conditions, and neutral plane position, aiming to realize the theoretical calculation and prediction of the extinguishing agent hold time in any real protection zone under given conditions through the leakage parameters obtained by fan testing. Although this method has made a step forward in theory, given the complexity of the extinguishing agent spraying physical process, the model applies multiple simplifying assumptions, including ignoring the influence of the extinguishing agent spraying process, assuming that the gas leakage is driven only by the static pressure difference, ignoring the leakage hole layer factor and only considering the case where the maximum pressure difference can be formed, the prediction results may underestimate the extinguishing agent leakage level due to the simplifying assumptions (especially the model cannot evaluate the leakage during the extinguishing agent spraying process), and the final output is only a predicted time value, which is used to determine whether the protection zone sealing should be enhanced, mainly serving the performance verification in the system acceptance stage. The defect of this method is that it still does not provide a simple and direct means to dynamically determine the specific adjustment amount of the extinguishing agent storage according to the actual changes in air tightness during the life cycle of the system, i.e., the extinguishing agent compensation amount.

[0005] Therefore, for the problem of long-term reliability decline of the total flooding gas extinguishing system caused by the inevitable long-term deterioration of the air tightness of the protection zone, the existing technology system still lacks a solution that can link the extinguishing agent hold time prediction to the functional extinguishing agent quantitative compensation. SUMMARY

[0006] The technical problem to be solved by the present application is how to overcome the problem in the prior art that the extinguishing agent concentration is difficult to maintain due to the long-term deterioration of the air tightness of the protection zone for the total flooding gas extinguishing system, and to provide a test device and method that can quantitatively determine the extinguishing agent compensation amount, thereby achieving active and accurate compensation, so as to significantly improve the long-term reliability of the system.

[0007] In order to achieve the above-mentioned purpose, in a first aspect, the present application provides a test device for extinguishing agent quality compensation of a total flooding gas extinguishing protection zone, comprising:

[0008] The protective zone model is composed of a ceiling, a bottom plate and side walls which enclose a limited space, and a plurality of sharp-edge round holes are distributed on the side walls;

[0009] The air-tightness adjusting and testing system comprises opening adjusting electromagnetic valves respectively installed on the sharp-edge round holes, and a fan and an electronic differential pressure gauge installed at a door frame of the protective zone model;

[0010] The global heating and extinguishing agent spraying linkage system comprises an extinguishing agent storage tank connected with atomizing nozzles, and a heating assembly covering the outer surface of the protective zone model;

[0011] The data monitoring system comprises thermocouples, static pressure sensors and concentration sensors arranged inside the protective zone model; and

[0012] The control terminal is in communication connection with the data monitoring system and is configured to:

[0013] Control all the opening adjusting electromagnetic valves to synchronously act to build at least five air-tightness modes with gradients in the protective zone model, and fit a quantitative relationship between a leakage rate parameter and an extinguishing agent mass compensation amount based on fan testing data and extinguishing agent spraying data in each mode.

[0014] As an optional implementation, one side of the opening adjusting electromagnetic valve is fixed to the sharp-edge round hole through a sealing thread, and the other side is in communication with an external atmospheric environment;

[0015] The opening adjusting electromagnetic valve can adjust the sectional area ratio of an internal pipeline thereof according to an instruction of the control terminal.

[0016] As an optional implementation, the heating assembly comprises electric heating sheets respectively and independently attached to the outer surfaces of the ceiling, the bottom plate, the door and each side wall, and a temperature measurement and control integrator for receiving a target temperature instruction of the control terminal and independently controlling the on-off of each electric heating sheet.

[0017] As an optional implementation, the data monitoring system further comprises a plurality of support cables and fixed corner points arranged on the support cables;

[0018] The thermocouples, the static pressure sensors and the concentration sensors are fixed to the fixed corner points in groups and arranged symmetrically or globally in the internal space of the protective zone model.

[0019] In a second aspect, the application further provides an extinguishing agent mass compensation testing method for a full-submersion gas extinguishing protective zone based on the above testing device, comprising the following steps:

[0020] Step S1: The control terminal adjusts the opening adjusting electromagnetic valves to a preset opening degree, so that the protective zone model forms a specific air-tightness mode;

[0021] Step S2: In the current airtightness mode, use the fan to perform a pressurization test to obtain a leakage rate function coefficient;

[0022] Step S3: In the current airtightness mode, control the fire extinguishing agent tank to spray the fire extinguishing agent, use the data monitoring system to collect data in the spraying and impregnation stages, and calculate the fire extinguishing agent mass compensation amount;

[0023] Step S4: Change the preset opening degree, repeat steps S1 to S3 at least five times, and obtain data under different airtightness modes;

[0024] Step S5: Based on the fitting of multiple sets of leakage rate function coefficients and fire extinguishing agent mass compensation amount data, a fire extinguishing agent mass compensation model is constructed.

[0025] As an optional implementation, step S2 specifically includes:

[0026] Control the fan to supply air to the protection zone model, and select at least 5 pressure difference values in a preset pressure range ;

[0027] Adjust the fan speed to stabilize the indoor and outdoor pressure difference at each of the pressure difference values, and record the corresponding fan flow ;

[0028] Use the least squares method to fit the pressure difference values and the fan flow as a power function , wherein is the flow coefficient, is the pressure index;

[0029] Correct the flow coefficient to the standard state to obtain , and then obtain the standard leakage rate function: , wherein is the volume of the protection zone model, is the standard flow coefficient, is the leakage rate under the pressure difference .

[0030] As an optional implementation, the method for calculating the fire extinguishing agent mass compensation amount in step S3 is:

[0031] Map the geometric space of the protection zone model to a unit cubic space domain and perform grid discretization;

[0032] Use shape functions to interpolate the discrete data collected by the thermocouple, static pressure sensor, and concentration sensor to the entire space domain;

[0033] Calculate the volume-weighted average indoor static temperature, static pressure, and fire extinguishing agent concentration by numerical integration;

[0034] Estimating the residual mass of the extinguishing agent at the end of the impregnation stage by means of a gas state equation and the mass compensation amount is calculated according to the formula wherein is the designed filling amount of the extinguishing agent, is the mass compensation amount of the extinguishing agent.

[0035] As an optional implementation, the extinguishing agent mass compensation model constructed in step S5 is:

[0036] ;

[0037] wherein, is the standard air leakage rate under a pressure difference of 50 Pa, is the extinguishing agent discharge duration, is the impregnation duration (usually 10 min), , is a dimensionless empirical coefficient, is an empirical constant.

[0038] The calculation formula of the extinguishing agent mass compensation coefficient determined based on the compensation model is:

[0039] ;

[0040] wherein, is a dimensionless constant related to , .

[0041] In step S1, the preset opening degree includes five gradient levels of 0.05, 0.25, 0.45, 0.65 and 0.85;

[0042] And before step S3, it further includes a step of heating the protection zone model to a target temperature by the heating assembly.

[0043] ​This invention constructs a dedicated testing device with precisely adjustable airtightness. By simulating a series of standard leakage conditions from optimal to suboptimal on this device, and directly conducting experiments on the entire process of extinguishing agent release and impregnation, the invention obtains data on the extinguishing agent mass loss corresponding to different leakage levels. Based on this, the invention abandons the path of constructing a simplified physical model, instead employing an inductive method based on experimental data. It mathematically fits the measured leakage rate parameter with the extinguishing agent mass compensation amount, establishing a concise empirical relationship model such as an exponential function between the two. The method contained in this invention is essentially a paradigm, its significance being that: after conducting the tests described in this invention on a typical representative protected area, for any actual protected area similar to the test model, only routine airtightness testing is needed during its operation and maintenance to obtain the current leakage rate, which can then be directly substituted into this empirical model to quickly calculate the extinguishing agent mass compensation coefficient or specific compensation amount required to ensure long-term reliability. This allows maintenance personnel to precisely increase extinguishing agent reserves based on the results of regular airtightness tests, transforming the static design dosage into a dynamic, optimized dosage that matches the actual airtightness condition.

[0044] Therefore, this invention not only provides a brand-new testing tool, but also establishes a quantifiable and executable systematic maintenance method, which essentially elevates the reliability management of total flooding gas fire suppression systems from post-event remediation and complex prediction to a new level of pre-event planning and precise maintenance, and has significant engineering practical value and technological advancement. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0046] Figure 1 A schematic diagram of the combined structure of the protective zone model and the airtightness adjustment and testing integrated system in the testing apparatus provided in the embodiments of the present invention, wherein:

[0047] Figure 1 (a) in the figure is a schematic diagram of the front three-dimensional structure of the combined structure;

[0048] Figure 1 (b) in the figure is a schematic diagram of the rear three-dimensional structure of the combined structure;

[0049] Figure 1 (c) in the diagram is a schematic diagram of the internal or side perspective structure of the composite structure;

[0050] Figure 2 A schematic diagram of the combined structure of the protected area model and the global heating and extinguishing agent discharge linkage system in the test device provided in the embodiments of the present invention, wherein:

[0051] Figure 2 (a) in the figure is a schematic diagram of the front three-dimensional structure of the combined structure;

[0052] Figure 2 (b) in the figure is a top view or a top three-dimensional structural diagram of the combined structure;

[0053] Figure 2 (c) in the diagram is a schematic diagram of the internal perspective structure of the composite structure;

[0054] Figure 3 A magnified and perspective view of a partial structure of the data monitoring system in the testing apparatus provided in this embodiment of the invention;

[0055] Figure 4 A schematic diagram of a non-uniformly distributed airtightness scheme achieved by an opening-adjusting solenoid valve in the testing device provided in this embodiment of the invention, wherein:

[0056] Figure 4 (a) in the figure is a schematic diagram of the airtightness distribution when the opening degree of the fully open regulating solenoid valve is 1 (fully open);

[0057] Figure 4 (b) is a schematic diagram of the airtightness distribution when the opening degree of the solenoid valve for adjusting the opening degree on one of the walls is 0 (closed);

[0058] Figure 4 (c) is a schematic diagram of the airtightness distribution on two of the wall surfaces when the opening degree of the solenoid valves is 0.

[0059] Figure 4 (d) in the diagram is a schematic diagram of the airtightness distribution when the opening degree of the solenoid valve for adjusting the opening degree is 1 on only one wall surface;

[0060] Figure 4 (e) in the diagram is a schematic diagram of the airtightness distribution when the opening of the solenoid valve for adjusting the opening is 0 at only one height level;

[0061] Figure 4 (f) in the figure is a schematic diagram of the airtightness distribution when the opening degree of the solenoid valve for adjusting the opening degree is 1 at only one height level;

[0062] Figure 5 This is a schematic diagram of the changes in the volume fraction of the extinguishing agent and the concentration stratification phenomenon within the protected area model in an embodiment of the present invention (based on CFD numerical simulation and experimental monitoring).

[0063] Figure 6 This is a comparison chart of the volume fraction of extinguishing agent calculated by the simple arithmetic mean method and the volume weighted average method, respectively, in an embodiment of the present invention;

[0064] Figure 7For the embodiment of the present application, the mass compensation amount and compensation coefficient empirical function fitting step and curve verification diagram of the fire extinguishing agent (taking perfluorohexanone as an example);

[0065] In the figure: 1-1, ceiling; 1-2, door side wall surface; 1-3, wall surface without door and window No. 1; 1-4, window side wall surface; 1-5, wall surface without door and window No. 2; 1-6, bottom plate; 2, door; 3, window; 4, sharp edge circular hole; 5, opening adjusting electromagnetic valve; 6, fan mounting frame and skin; 7, fan; 8, pressure communication pipe; 9, electronic differential pressure gauge; 10, control terminal; 11, fire extinguishing agent storage tank; 12, spray control electromagnetic valve; 13, metal braided hose; 14, atomizing nozzle; 15, electric heating sheet; 15-1 ceiling heating sheet, 15-2 door body heating sheet, 15-3 door side wall surface heating sheet, 15-4 wall surface without door and window No. 1 heating sheet, 15-5 window side wall surface heating sheet, 15-6 wall surface without door and window No. 2 heating sheet, 15-7 bottom plate heating sheet; 16, temperature measurement and control integrator; 17, electronic balance; 18, data recorder; 19, fixed corner point; 20, supporting cable; 21, concentration sensor; 22, thermocouple; 23, static pressure sensor. DETAILED DESCRIPTION

[0066] Example 1

[0067] The present embodiment provides a fire extinguishing agent mass compensation test device for a total flooding gas fire extinguishing protection zone. The device is mainly used to solve the problem that the quantitative relationship between the gas tightness degradation of the protection zone and the loss amount of the fire extinguishing agent cannot be quantified in the prior art. Through the device, a variety of standardized gas tightness conditions can be simulated in a laboratory environment, and combined with real fire extinguishing agent spray experiments, a fire extinguishing agent mass compensation formula for guiding engineering practice can be derived. The overall architecture of the device includes a protection zone model, a gas tightness adjustment and test system, a global heating and fire extinguishing agent spray linkage system, a data monitoring system, and a control terminal 10 as the core control center.

[0068] First, as the geometric basis of the entire test device, the protection zone model constructs a controllable restricted space for simulating the protection zone environment of data centers, archives and other protection zones in actual applications. For example, Figure 1 (a) and Figure 1As shown in (b) of FIG. 1, the protection zone model is enclosed by a ceiling 1-1, a floor 1-6, and four side walls connected between the ceiling and the floor. The specific side wall structure includes a door side wall 1-2 on which a door 2 is installed, a window side wall 1-4 on which an observation window 3 is installed, and oppositely arranged doorless window No. 1 wall 1-3 and doorless window No. 2 wall 1-5. In order to ensure that the model does not deform when subjected to the instantaneous high pressure (positive or negative pressure) generated during the discharge of fire extinguishing agent, all of the above-mentioned enclosure structure components, including the ceiling 1-1, the floor 1-6, and the various side walls, can be made of SUS304 stainless steel material with a thickness of 2 mm, 10 mm, or even thicker. The connection between each plate can adopt a full welding process, and in order to eliminate the small pores that may be generated during the welding process, all the joints are filled and sealed again using pressure-resistant structural glue. In addition, a cross-shaped reinforcing framework can be welded on the outer wall of the protection zone model to further enhance the rigidity of the structure. As an optional implementation parameter, the internal space size of the protection zone model in this embodiment is designed to be 2500 mm long, 2500 mm wide, and 2400 mm high, thereby forming a test cavity with a net volume of 15 cubic meters. The door 2 adopts a single-layer hollow design to ensure the flatness and strength of the door body; the window 3 selects a 20 mm thick tempered glass equipped with an aluminum alloy frame, which not only meets the need of observing the internal discharge phenomenon, but also ensures the overall pressure-bearing capacity.

[0069] In order to simulate various air leakage conditions that may occur on the enclosure structure of the protection zone and achieve accurate control of the air leakage amount, a plurality of sharp-edge circular holes 4 are designed and distributed on the side walls of the protection zone model. As shown in (a) of FIG. 2, Figure 1 As shown in (c) of FIG. 1, Figure 1 These sharp-edge circular holes 4 can be provided with a total of 32, which are evenly arranged on the door side wall 1-2, the doorless window No. 1 wall 1-3, the window side wall 1-4, and the doorless window No. 2 wall 1-5, while the ceiling 1-1 and the floor 1-6 remain intact without holes to simulate the characteristics of wall leakage in actual buildings. Alternatively, 6 sharp-edge circular holes 4 are arranged on the door side wall 1-2, 8 on the window side wall 1-4, and 9 on each of the two larger doorless window walls. The diameter of each basic sharp-edge circular hole 4 can be set to 1 cm, and this size design can provide a maximum actual air leakage area of about 25.133 cm 2 when all the holes are fully open, which is sufficient to cover the leakage conditions of most typical protection zones.

[0070] In cooperation with the above-mentioned sharp-edge circular holes 4, the device is equipped with an air tightness adjusting and testing system. The system includes an opening adjusting electromagnetic valve 5 installed on each sharp-edge circular hole 4, and a fan 7 and an electronic differential pressure gauge 9 for air tightness testing. As shown in (b) of FIG. 2, Figure 1As shown in (c) of FIG. 1, one side of the opening-regulating electromagnetic valve 5 is directly fixed on the sharp-edge round hole 4 by a high-air-tightness sealing screw thread, and the other side is directly connected to the external atmosphere. This connection ensures that when the opening-regulating electromagnetic valve 5 is opened, the gas exchange between the inside and outside of the protection zone can only be carried out through the valve body channel, excluding the interference of other uncontrolled paths. Each opening-regulating electromagnetic valve 5 has a valve core structure with an adjustable cross-sectional area, which can receive analog or digital instructions from the control terminal 10, and the instructions can accurately control the valve opening in the [0, 1] interval (with a precision of 0.1).

[0071] Unlike the method of regulating air tightness by fixed orifices or a single centralized air leakage point in the prior art, the 32 opening-regulating electromagnetic valves 5 in the embodiment can be controlled by the control terminal 10 to perform synchronous actions, or can be independently programmed to build a non-uniform air tightness scheme.

[0072] In order to more realistically simulate the non-uniform air leakage phenomenon that may exist in actual buildings (such as unilateral distribution of construction gaps, specific height distribution of pipe well wall holes, etc.), as shown in (a) of FIG. 2, by setting the combination of valve openings at different positions through the control terminal 10, various typical non-uniform air tightness test schemes can be built: Figure 4

[0073] As shown in (a) of FIG. 3, all electromagnetic valves are fully opened to simulate an extreme high-leakage working condition; Figure 4

[0074] As shown in (b) of FIG. 4 and (c) of FIG. 5, the electromagnetic valves on a single wall or adjacent two walls are respectively controlled to be fully closed, and the rest are kept open, to simulate the sealing difference of building walls in different directions; Figure 4 Figure 4 As shown in (d) of FIG. 6, only the electromagnetic valves on a certain wall are opened to simulate a specific scene of unilateral strong wind pressure or unilateral damage leakage;

[0075] As shown in (e) of FIG. 7 and (f) of FIG. 8, the control capability in the vertical dimension is shown, i.e., only the electromagnetic valves at a certain height layer or only the electromagnetic valves at a certain height layer are closed, so as to study the specific influence of different height leakages on the concentration maintenance time in view of the gravitational settling characteristics of the fire extinguishing agent gas. Figure 4

[0076] This non-uniform field building capability based on independent valve control enables the device to approach the complex air leakage distribution in reality, overcoming the technical limitations of traditional devices that can only simulate uniform air leakage or single orifice air leakage. Figure 4 Figure 4

[0077] This non-uniform field building capability based on independent valve control enables the device to approach the complex air leakage distribution in reality, overcoming the technical limitations of traditional devices that can only simulate uniform air leakage or single orifice air leakage.

[0078] ​​​​​​Furthermore, thanks to its high-precision opening control, this device can simulate extremely low air leakage rates. Experiments show that when the opening of the solenoid valve is less than 0.2, the standard air leakage rate of the tested protected area model can be lower than 1.0 h. -1 Even reaching 0.6h -1 The following means that this device is not only suitable for conventional buildings, but also meets the requirements of the "Technical Standard for Near-Zero Energy Buildings" GB / T51350 for near-zero energy public buildings (≤1.0h). -1 Even near-zero energy residential buildings (≤0.6h) -1 The requirements for testing the retention performance of extinguishing agents in high-airtightness environments, such as fire extinguishing agent storage environments.

[0079] The airtightness test of the protected area model was conducted using a fan pressurization method. For example... Figure 1 As shown in (a), fan 7 is mounted on a specially designed fan mounting frame and skin 6. The dimensions of the fan mounting frame and skin 6 are strictly matched to the dimensions of the door frame of door 2. During testing, door 2 is opened, and the fan mounting frame and skin 6 are tightly pressed into the door frame. The sealing strip around them completely isolates the airflow inside and outside the protected area model, ensuring that all airflow entering and exiting the model must pass through fan 7. Fan 7 can be a variable frequency speed-regulating axial flow fan, with the airflow direction set to blow air into the protected area model (positive pressure mode for fan testing). Fan 7 is connected to control terminal 10 via a data cable, and control terminal 10 automatically adjusts the speed according to the test requirements. In order to measure the pressure difference inside and outside the protected area model when fan 7 is working, the system is also equipped with electronic differential pressure gauge 9 and pressure connecting pipe 8. After completing the leakage rate test in step S2, fan 7, fan mounting frame and skin 6, and electronic differential pressure gauge 9 need to be removed from the protected area model to eliminate any flow field interference or thermal interference that they may cause in the subsequent extinguishing agent discharge test, ensuring the purity of the data during the discharge stage. One end of the pressure connecting pipe 8 passes through the fan mounting frame and skin 6 and extends into the interior of the protected area model. This port is designed to be located in the static pressure zone away from the jet area of ​​the fan 7. The other end is connected to an externally placed electronic differential pressure gauge 9. The electronic differential pressure gauge 9 needs to have high-precision measurement capabilities and be able to feed back minute pressure difference changes to the control terminal 10 in real time.

[0080] To replicate the ambient temperature and extinguishing agent release process during a fire, the device integrates a global heating and extinguishing agent release linkage system. For example... Figure 2 (a) and Figure 2The system includes a fire extinguishing agent storage tank 11 installed above the ceiling 1-1, heating assemblies covering each outer surface of the protective zone model, and related control actuators. The fire extinguishing agent storage tank 11 is of an internal pressure storage structure, placed on an electronic scale 17 for real-time monitoring of the weight change of the fire extinguishing agent storage tank 11 during spraying, thereby accurately calculating the mass flow of the fire extinguishing agent. The fire extinguishing agent storage tank 11 is connected to the atomizing nozzle 14 located at the geometric center of the ceiling 1-1 inside the protective zone model through a metal braided hose 13. The metal braided hose 13 can be of DN32 specification with a pressure resistance of 10 MPa. A spraying control electromagnetic valve 12 is also provided in the pipeline, which receives instructions from the control terminal 10 to control the start and stop of fire extinguishing agent spraying. The atomizing nozzle 14 can be designed with a multi-hole cyclone to rapidly atomize and uniformly distribute the liquid fire extinguishing agent into the test space.

[0081] In order to study the influence of different environmental temperatures on air tightness and fire extinguishing agent maintenance time, the heating assembly is designed as a full wrap. As shown in Figure 2 (a) to Figure 2 (c), the electric heating film 15 is independently attached to each outer surface of the protective zone model, including: ceiling heating film 15-1 attached to the outer surface of the ceiling 1-1, door body heating film 15-2 attached to the outer surface of the door body 2, door side wall heating film 15-3 attached to the outer surface of the door side wall 1-2, door windowless No. 1 wall heating film 15-4 attached to the outer surface of the door windowless No. 1 wall 1-3, window side wall heating film 15-5 attached to the outer surface of the window side wall 1-4, door windowless No. 2 wall heating film 15-6 attached to the outer surface of the door windowless No. 2 wall 1-5, and bottom plate heating film 15-7 attached to the lower surface of the bottom plate 1-6. The power density of these electric heating films 15 is designed to be 0.2 W / cm 2 to 0.3 W / cm 2 , and the total power can meet the rapid heating demand. The temperature measurement and control integrator 16 is matched therewith, which is connected to each electric heating film 15 through a cable and can be internally provided with multiple PT-100 temperature sensors for monitoring the temperature of each wall surface. The temperature measurement and control integrator 16 receives the target temperature instruction (for example, 70℃) from the control terminal 10, independently controls the on-off of each electric heating film 15 through the PID algorithm, thereby achieving uniform and accurate control of the overall temperature of the protective zone model.

[0082] The data monitoring system is the key to verify the experimental results, as shown in Figure 2 (c) and Figure 3As shown, the system includes thermocouples 22, static pressure sensors 23 and concentration sensors 21 arranged in the internal space of the protection zone model. In order to obtain data representative of the space, these sensors are not placed randomly, but are arranged in a stereoscopic grid through the multi-layer support cables 20 and the fixed corner points 19 arranged on the support cables 20. Optionally, the support cables 20 are provided with 4 layers, respectively located at the horizontal planes with a height of 480mm, 960mm, 1440mm and 1920mm from the bottom plate 1-6. On each layer of support cables 20, according to the geometric symmetry of the protection zone space, there are 4 fixed corner points 19. On each fixed corner point 19, a thermocouple 22 (such as a T-type thermocouple), a static pressure sensor 23 (such as a piezoresistive pressure sensor) and a concentration sensor 21 (such as a thermal conductivity type concentration sensor) are fixed in groups. This symmetrical or global coverage arrangement enables the sensor network to capture the three-dimensional distribution of the temperature field, pressure field and concentration field in the protection zone. All sensors are connected to the external data logger 18 through signal lines, and the data logger 18 is responsible for high-frequency acquisition of channel data and real-time transmission of data stream to the control terminal 10 for processing.

[0083] Finally, the control terminal 10 as the center of the whole device is electrically connected with the above-mentioned air tightness adjustment and test system (opening adjustment electromagnetic valve 5, fan 7, electronic differential pressure gauge 9), global heating and extinguishing agent spraying linkage system (spraying control electromagnetic valve 12, temperature control integrator 16, electronic balance 17) and data monitoring system (data logger 18). The control terminal 10 internally runs a special measurement and control software, which is configured to perform the following core functions:

[0084] Firstly, it can send a unified opening command to all 32 opening adjustment electromagnetic valves 5, thereby constructing at least five air tightness modes with gradients (for example, the openings are 0.05, 0.25, 0.45, 0.65, 0.85) in the protection zone model;

[0085] Secondly, under each air tightness mode, it can automatically control the fan 7 to perform multi-point differential pressure test to obtain flow and differential pressure data;

[0086] Then, it can link control heating and extinguishing agent spraying, and trigger data recording synchronously;

[0087] Finally, using the built-in calculation module, the control terminal 10 can calculate the air leakage rate parameter based on the fan 7 test data, calculate the real-time compensation amount of the extinguishing agent based on the sensor data, and finally fit the quantitative relationship model between the air leakage rate parameter and the quality compensation amount of the extinguishing agent.

[0088] Example Two:

[0089] The embodiment is based on the test device described in embodiment one, and provides a fire extinguishing agent quality compensation test method for a full-submersion gas fire extinguishing protection zone. The method solves the problem of lacking quantitative compensation basis for gas tightness degradation in the prior art by conducting systematic physical tests in a controlled experimental model and combining mathematical fitting methods. The method includes steps S1 to S5 in logical order, which will be described in detail one by one.

[0090] First, step S1 is performed: the control terminal 10 adjusts the opening degree of the electromagnetic valve 5 to a preset opening degree, so that the protection zone model forms a specific gas tightness mode. Before the experiment starts, in order to ensure that the actual air leakage area is only controlled by the sharp edge circular hole 4 and the opening degree adjustment electromagnetic valve 5, the protection zone model needs to be pre-inspected and leak-stopped. The specific operation is as follows: install the fan mounting frame and the skin 6 in place, instruct all opening degree adjustment electromagnetic valves 5 to be completely closed by the control terminal 10, start the fan 7 to inject colored smoke into the model, and check whether the smoke leaks from the weld gap, door and window joint, etc. under the condition of maintaining a certain positive pressure. If a leak is found, use pressure-resistant structural adhesive to seal it until the basic gas tightness of the model meets the experimental requirements. Then, the gradient mode construction stage is entered. The control terminal 10 sends a first group of preset opening degree instructions to all opening degree adjustment electromagnetic valves 5, for example, the opening degree is set to 0.05. At this time, the actual air leakage area of the protection zone model is accurately set, forming the first gas tightness mode. According to the experimental design, the preset opening degree usually includes five gradient levels of 0.05, 0.25, 0.45, 0.65 and 0.85, which represent five working conditions of the gas tightness of the protection zone model from best to worst.

[0091] After the construction of the current gas tightness mode is completed, step S2 is performed: under the current gas tightness mode, the fan 7 is used for pressure increase test to obtain the air leakage rate function coefficient. This step aims to quantify the current leakage characteristics through aerodynamic test. The specific process includes: the control terminal 10 drives the fan 7 to start and continuously supplies air to the inside of the protection zone model. In order to obtain a reliable fitting curve, the control terminal 10 selects at least 5 target pressure difference values , for example 20Pa, 30Pa, 40Pa, 50Pa and 60Pa, in a preset pressure interval (usually 10Pa to 60Pa). The control terminal 10 adjusts the speed of the fan 7 so that the indoor and outdoor pressure difference values fed back by the electronic pressure difference meter 9 are stabilized at each of the above target values in turn. When the pressure difference is stable, the system records the speed of the fan 7 at the current time and the corresponding fan flow (calculated by the function relationship , which is calibrated by the fan factory characteristic curve). After collecting a group of , After the data is collected, the control terminal 10 uses a built-in algorithm to perform a regression analysis of the data using the least squares method (e.g., the Levenberg-Marquardt estimation method). According to the principles of fluid mechanics, the flow rate and the pressure difference follow a power function relationship, i.e. . Through fitting, the current flow rate coefficient and the pressure exponent can be calculated. The fitting process can be expressed as: the fan flow rate as the dependent variable , the pressure difference as the independent variable , and the fitting as a power function , where and , and the complete form of the function is .

[0092] In order to make the test results under different environments comparable, the flow rate coefficient also needs to be corrected to the standard state (20℃, 101.325kPa) according to the current air temperature and atmospheric pressure, to obtain the standard flow rate coefficient . The correction formula is as follows:

[0093] ;

[0094] wherein is the flow rate coefficient under the standard state, is the indoor static temperature of the protective zone model, is the indoor static pressure of the protective zone model, is the environmental static temperature, is the environmental static pressure, 293 is the Kelvin temperature value corresponding to 20℃, and 273 is the unit conversion constant.

[0095] Further, the standard air leakage rate function under the air tightness mode can be constructed as: wherein is the volume of the protective zone model (in this example, 15m 3 ), is the air leakage rate under the pressure difference , i.e., the number of air changes per second, which is the core physical quantity representing the air tightness of the protective zone, is the volume of the protective zone model.

[0096] Then, step S3 is performed: Under the current airtightness mode, the extinguishing agent storage tank 11 is controlled to release the extinguishing agent. Data from the release and impregnation stages is collected using a data monitoring system to calculate the extinguishing agent mass compensation. Before this step, as a preferred implementation method that more closely resembles a real fire scenario, a step of heating the protected area model to the target temperature using a heating component is also included. For example, the control terminal 10 sets the target temperature to 70°C, and the temperature control integrator 16 immediately closes the circuit of the electric heating element 15 to heat the model wall until the feedback temperature of the internal thermocouple 22 reaches the set value. At this time, the system enters standby mode. The control terminal 10 sends an opening signal to the release control solenoid valve 12, and the extinguishing agent (such as heptafluoropropane or perfluorohexanone) is instantly sprayed into the protected area model through the atomizing nozzle 14 under nitrogen drive. The electronic balance 17 records the decrease in the weight of the storage tank in real time. When the weight data stabilizes, the release is determined to be over, and the release duration is recorded. In the subsequent impregnation and holding phase (duration set to...), For example, 10 minutes), the thermocouple 22, static pressure sensor 23 and concentration sensor 21 in the data monitoring system synchronously collect temperature, pressure and extinguishing agent concentration data at various points in the protected area at a high frequency.

[0097] Step S3, which calculates the extinguishing agent mass compensation, employs the grid integration method. This method is chosen to address the calculation bias issues introduced by the traditional "simple arithmetic mean method." The specific calculation logic is as follows:

[0098] 1. Spatial Mapping and Mesh Discretization: Mapping the physical geometric space of the protected area model (considered as a hexahedron) to a unit cube parameter space. Define the mapping function. For the hexahedron model of the protected area, its mapping function can be a shape function. Represented as:

[0099] ;

[0100] in, These are the coordinates of the eight vertices of the protected area model.

[0101] Constructing the Jacobian matrix of the mapping The volume scaling factor is The parameter mapping space is discretized into Direction share, Direction portions, and Direction The orthogonal grid of portions, specifically represented as , , ,in , , , grid node coordinates .

[0102] 2. Physical quantity interpolation: the volume of each discrete element is , and the discrete element volume is approximated as when it is small enough, where , , . The measured data of sensors (thermocouple, static pressure sensor, concentration sensor) on the discrete element nodes (representing temperature, pressure or concentration) are interpolated to the entire spatial domain by a cubic linear shape function:

[0103] ;

[0104] where is the parameter index, all of which are taken in , in addition, is the shape function, , , and in the shape function is the normalized parameter, with a value range ;

[0105] 3. Volume-weighted average calculation: using numerical integration (such as the trapezoidal rule) to calculate the volume-weighted average of physical quantities in the entire space :

[0106] ;

[0107] Thus, the volume-weighted average of the extinguishing agent volume fraction , the average static temperature and the average static pressure are obtained.

[0108] Here, the significant advantages of using volume-weighted average algorithm are particularly explained. As shown in the CFD numerical simulation and experimental results Figure 5 , during the extinguishing agent immersion retention stage, due to the temperature difference and gas density difference between the inside and outside of the protection zone, fresh air from the outside usually enters through the upper air leakage channel, resulting in obvious concentration stratification phenomenon in the protection zone (i.e. low concentration in the upper part and high concentration in the lower part). If a conventional simple arithmetic average (i.e. only the readings of a few sensors are averaged) is used, Figure 6As shown, the calculation results tend to be lower than the real volume-weighted average. This means that the simple arithmetic average method will underestimate the average concentration level of extinguishing agent in the protection zone, and thus lead to an underestimation of the remaining extinguishing agent mass, and finally cause the calculated extinguishing agent compensation to be overestimated (i.e. "false" compensation). The volume-weighted average method based on the dense sensor network and grid discretization used in this embodiment can accurately capture the concentration field distribution in the space, effectively avoiding calculation errors caused by concentration stratification, and ensuring the scientificity and economy of the compensation calculation.

[0109] 4. Extinguishing agent remaining mass and compensation calculation: using the gas state equation to estimate the extinguishing agent remaining mass in the protection zone at the end of the immersion stage If the extinguishing agent and air mixture is regarded as an ideal gas, then:

[0110] ,

[0111] wherein, is the molar mass of the extinguishing agent, is the universal gas constant.

[0112] Finally, the extinguishing agent mass compensation is calculated by the following formula:

[0113] wherein, is the extinguishing agent design filling amount set at the beginning of the experiment (i.e. the ideal amount under the condition of no leakage).

[0114] Finally, step S5 is performed: fitting based on multiple sets of air leakage rate function coefficients and extinguishing agent mass compensation data to construct an extinguishing agent mass compensation model. In this embodiment, the model constructed is based on dimensional analysis and experimental data regression, and its mathematical expression is:

[0115] ;

[0116] wherein, represents the standard air leakage rate of the protection zone under a pressure difference of 50 Pa measured by the fan test; represents a natural exponential function; , are dimensionless empirical coefficients, which reflect the comprehensive influence of the protection zone geometry and the extinguishing agent physical properties on the leakage process; is an empirical constant used to correct the boundary conditions of the model.

[0117] The control terminal 10 uses the Levenberg-Marquardt algorithm or other nonlinear least squares algorithm to fit the five sets of data obtained in step S4, thereby solving , and The specific value.

[0118] To verify the reliability of this empirical model, numerous verification experiments were conducted in this embodiment. In a typical verification example, for a 15m... 3 A protective zone model was sprayed with 15 kg of perfluorohexanone extinguishing agent to construct four sets of standard leakage rates with different values ​​(the standard leakage rate was 1.27 h under a pressure difference of 50 Pa). -1 ~3.98h -1 (between). For example Figure 7 As shown, the experimental data were substituted into the above model for dimensionless fitting. The results show that the fitted curve is in high agreement with the experimental data, and the coefficient of determination R0 is [value missing]. 2 The value reaches 1. Under this specific working condition, the dimensionless empirical coefficient is calculated. , and dimensionless constants related to empirical constants. This confirms that the empirical model proposed in this embodiment can describe the nonlinear relationship between airtightness degradation and extinguishing agent loss very well, and has extremely high prediction accuracy and engineering practical value.

[0119] Once the above model parameters are determined, the extinguishing agent mass compensation coefficient can be further derived. The calculation formula is used to guide practical engineering applications. Based on the compensation model, the compensation coefficient... Defined as the ratio of the actual required filling amount to the designed amount, the derived formula is:

[0120] ;

[0121] In this formula, It is related to the empirical constant The relevant dimensionless constants (specific relationships are as follows) The physical meaning of this formula is that, for any actual protected area with similar geometric features and extinguishing agent type to the test model, engineers only need to obtain its... and The value is substituted into the formula to obtain the compensation coefficient. In the original design quantity Multiply by a coefficient This allows for the direct calculation of the actual extinguishing agent charge required to maintain the specified duration. This method significantly improves the reliability of total flooding gas extinguishing systems throughout their entire lifecycle, representing a technological leap from "passive detection" to "active compensation."

Claims

1. A testing device for extinguishing agent mass compensation in a total flooded gas extinguishing protection zone, characterized in that, include: The protective zone model consists of a ceiling (1-1), a base plate (1-6), and side walls that enclose a confined space. Multiple sharp-edged circular holes (4) are distributed on the side walls. The side wall structure includes a door side wall (1-2) with a door (2) installed, a window side wall (1-4) with an observation window (3) installed, and a doorless and windowless first wall (1-3) and a doorless and windowless second wall (1-5) arranged opposite to each other. The sharp-edged circular holes (4) are evenly arranged on the door side wall (1-2), the doorless and windowless first wall (1-3), the window side wall (1-4), and the doorless and windowless second wall (1-5). The airtightness adjustment and testing system includes an opening adjustment solenoid valve (5) installed on each of the sharp-edged circular holes (4), and a fan (7) and an electronic differential pressure gauge (9) installed on the door frame of the protected area model. The global heating and extinguishing agent discharge linkage system includes an extinguishing agent storage tank (11) connected to an atomizing nozzle (14), and a heating component covering the outer surface of the protected area model; The data monitoring system includes thermocouples (22), a static pressure sensor (23), and a concentration sensor (21) arranged inside the protected area model; and a control terminal (10) which is communicatively connected to the data monitoring system and is configured as follows: All opening adjustment solenoid valves (5) are controlled to operate synchronously to construct at least five airtightness modes with gradients in the protected area model, and based on the fan (7) test data and extinguishing agent discharge data in each mode, the quantitative relationship between the air leakage rate parameter and the extinguishing agent mass compensation amount is obtained by fitting.

2. The extinguishing agent mass compensation testing device for a total flooded gas extinguishing protection zone according to claim 1, characterized in that: One side of the opening adjustment solenoid valve (5) is fixed to the sharp-edged circular hole (4) by a sealing thread, and the other side is connected to the external atmospheric environment; The opening adjustment solenoid valve (5) can adjust the cross-sectional area ratio of its internal pipe according to the instructions of the control terminal (10).

3. The extinguishing agent mass compensation testing device for a total flooded gas extinguishing protection zone according to claim 1, characterized in that: The heating assembly includes electric heating elements (15) that are independently attached to the outer surfaces of the ceiling (1-1), the base plate (1-6), the door (2), and each side wall; and a temperature measurement and control integrator (16) which is used to receive the target temperature command from the control terminal (10) and independently control the on / off state of each electric heating element (15).

4. The extinguishing agent mass compensation testing device for a total flooded gas extinguishing protection zone according to claim 1, characterized in that: The data monitoring system also includes multi-layer support cables (20) and fixed corner points (19) set on the support cables (20). The thermocouple (22), static pressure sensor (23) and concentration sensor (21) are fixed in groups on the fixed corner point (19) and arranged symmetrically or in full coverage within the space of the protected area model.

5. A method for testing the extinguishing agent mass compensation in a total flooded gas extinguishing protection zone based on the testing apparatus described in any one of claims 1 to 4, characterized in that, Includes the following steps: Step S1: The control terminal (10) adjusts the opening adjustment solenoid valve (5) to the preset opening to make the protected area model form a specific airtightness mode; Step S2: Under the current airtightness mode, use the fan (7) to perform a pressurization test and obtain the leakage rate function coefficient; Step S3: Under the current airtightness mode, control the fire extinguishing agent storage tank (11) to release the fire extinguishing agent, use the data monitoring system to collect data on the release and impregnation stages, and calculate the fire extinguishing agent mass compensation amount; Step S4: Change the preset opening degree and repeat steps S1 to S3 at least five times to obtain data under different airtightness modes; Step S5: Fit multiple sets of leakage rate function coefficients with extinguishing agent mass compensation data to construct an extinguishing agent mass compensation model; Step S2 specifically includes: Control the fan (7) to deliver air into the protected area model, and select at least 5 pressure difference values ​​within the preset pressure range. ; Adjust the fan (7) speed to stabilize the indoor and outdoor pressure difference at the respective pressure difference values, and record the corresponding fan (7) flow rate. ; The pressure difference value and the fan (7) flow rate were fitted to a power function using the least squares method. ,in, For flow coefficient, Stress index; Flow coefficient Corrected to standard state This leads to the standard air leakage rate function: ,in For the volume of the protected area model, The standard flow coefficient, In order to achieve differential pressure The air leakage rate is below; The fire extinguishing agent mass compensation model constructed in step S5 is as follows: ； in, The standard air leakage rate is given under a pressure difference of 50 Pa. This refers to the duration of the extinguishing agent release. For soaking time, , These are dimensionless empirical coefficients. Let be an empirical constant, where Design the filling volume for the extinguishing agent. This is the amount of extinguishing agent mass compensation.

6. The method for testing the extinguishing agent mass compensation in a total flooded gas fire extinguishing protection zone according to claim 5, characterized in that, The method for calculating the extinguishing agent mass compensation in step S3 is as follows: The geometric space of the protected area model is mapped to the unit cube spatial domain and then discretized into a mesh. The discrete data collected by thermocouple (22), static pressure sensor (23) and concentration sensor (21) are interpolated into the entire spatial domain using shape functions; The volume-weighted average of indoor static temperature, static pressure, and extinguishing agent concentration was calculated by numerical integration. Estimate the remaining mass of extinguishing agent at the end of the impregnation stage using the gas law. And according to the formula Calculate the mass compensation amount.

7. The method for testing the mass compensation of extinguishing agent in a total flooded gas fire extinguishing protection zone according to claim 5, characterized in that, Extinguishing agent mass compensation coefficient determined based on compensation model The calculation formula is: ； in, To and The relevant dimensionless constants.

8. The method for testing the extinguishing agent mass compensation in a total flooded gas fire protection zone according to claim 5, characterized in that: In step S1, the preset opening includes five gradient levels: 0.05, 0.25, 0.45, 0.65, and 0.

85. Furthermore, before step S3, the process includes heating the protected area model to the target temperature using a heating component.

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