Fire environment prediction and analysis system

Abstract

The invention relates to a fire environment prediction and analysis system. The system comprises an input module used for inputting comburent predicted to burn and environment parameters; the project library module is internally pre-stored with projects, needing to be predicted and analyzed, of comburent, and the project library module matches combustion parameters corresponding to the comburent which is predicted to be combusted with environmental parameters; the calculation module calculates the carbon monoxide output, the flame height and the emission rate generated after combustion of the comburent through a preset formula, automatically matches the physicochemical properties of the carbon monoxide by taking the carbon monoxide as a risk substance, calculates the maximum toxic concentration and the farthest influence distance, and sends the maximum toxic concentration and the farthest influence distance to the control module; if the maximum toxicity concentration is greater than the atmospheric toxicity end point concentration, the graph drawing module draws a risk influence range graph and outputs the risk influence range graph through the output module; if the concentration is less than the atmospheric toxicity endpoint concentration, the output module outputs a prediction analysis report. The workload is greatly reduced; and the working efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of fire prediction, and in particular to a fire environment prediction and analysis system. Background Art

[0002] With the continuous improvement of environmental protection efforts, the accuracy requirements for fire accident risk analysis in environmental impact assessments and fire accident risk analysis in emergency plans for sudden environmental events are becoming higher and higher. However, since the prediction and analysis involve a large number of parameter values ​​and calculation demonstrations, such as boiling point, specific heat capacity at constant pressure, heat of vaporization, etc., which require sub-parameter query and analysis and calculation based on the characteristics of the material, it brings a large workload and reduces work efficiency. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a fire environment prediction and analysis system.

[0004] The technical solution of the present invention to solve the above technical problem is as follows: a fire environment prediction and analysis system, including an input module, a project library module, a control module, a graphics drawing module and an output module;

[0005] The input module is used to input the combustion materials predicted to be burned and the environmental parameters, and the input module is in communication connection with the project library module;

[0006] The project library module has pre-stored items of combustion objects that need to be predicted and analyzed, and the project library module matches the combustion parameters corresponding to the combustion objects predicted to be burned with the environmental parameters, and the project library module is in communication connection with the calculation module;

[0007] The calculation module is communicatively connected with the graphics drawing module, and the graphics drawing module is communicatively connected with the output module. The calculation module calculates the amount of carbon monoxide produced, the flame height and the emission rate after the combustion of the combustible material through a preset formula, and takes carbon monoxide as a risk substance, automatically matches the physical and chemical properties of carbon monoxide, calculates the maximum toxicity concentration and the farthest impact distance, and compares the maximum toxicity concentration with the atmospheric toxicity endpoint concentration. If it is greater than the atmospheric toxicity endpoint concentration, the graphics drawing module draws a risk impact range map according to the farthest impact distance and outputs it through the output module; if it is less than the atmospheric toxicity endpoint concentration, the graphics drawing module does not need to draw, and the output module outputs a prediction analysis report.

[0008] On the basis of the above technical solution, the present invention can also make the following improvements to the above technical solution:

[0009] Furthermore, the environmental parameters include ambient temperature, liquid pool area and predicted extinguishing time.

[0010] Furthermore, the combustion parameters include heat of combustion, specific heat capacity at constant pressure, boiling point and heat of vaporization.

[0011] Furthermore, the projects pre-stored in the project library module include project names, project boundaries and risk source locations.

[0012] Further, the preset formula includes sulfur dioxide emission rate kg / h: G 二氧化硫 =2BS, B—combustion amount of substance, kg / h; S—sulfur content in substance, %.

[0013] Furthermore, the preset formula also includes the amount of carbon monoxide produced kg / s: G 一氧化碳 =2330qCQ, C—carbon content in the substance, taken as 85%; q—chemical incomplete combustion value, taken as 1.5%-6.0%; Q—mass of substance participating in combustion, t / s.

[0014] Furthermore, the preset formula also includes the puff stability index Ri:

[0015] Furthermore, the physical and chemical properties of the carbon monoxide include molecular weight, boiling point, density, saturated vapor pressure and toxicity concentration.

[0016] The beneficial effects of the present invention are: by organically integrating parameters such as the amount of risk substances involved in combustion, the amount of carbon monoxide associated with fire accidents, and flame height, automatic identification and matching of other required parameters can be achieved through the input of a small number of parameters, and the fire accident risk prediction analysis and risk impact range map drawing can be completed simultaneously, thereby achieving the purpose of greatly reducing workload and improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a block diagram of the prediction and analysis system of the present invention.

[0018] The reference numerals are recorded as follows: 1. Input module; 2. Project library module; 3. Calculation module; 4. Graphics drawing module; 5. Output module. DETAILED DESCRIPTION

[0019] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0020] like Figure 1 As shown, the present invention discloses a fire environment prediction and analysis system, including an input module 1, a project library module 2, a control module, a graphics drawing module 4 and an output module 5;

[0021] The input module 1 is used to input the predicted combustible material and environmental parameters. The combustible material is carbon monoxide or sulfur dioxide. The input module 1 is connected to the project library module 2 in communication. The environmental parameters include ambient temperature, liquid pool area and predicted extinguishing time. The ambient temperature affects the ignition rate and combustion efficiency of the combustible material. In a high temperature environment, the combustible material is more likely to reach the ignition point and the fire spreads faster. The ambient temperature will also affect the effect of the fire extinguishing agent. For example, high temperature may accelerate the evaporation of water and reduce its cooling effect. In fires involving flammable liquids, the liquid pool area determines the scale of the fire and the range of heat radiation. A larger liquid pool area will result in a higher heat release rate and a larger flame, which increases the difficulty of extinguishing the fire. The liquid pool area also affects the distribution and usage of the fire extinguishing agent, requiring more fire extinguishing resources to cover the entire fire source.

[0022] The project library module 2 pre-stores projects of combustibles that need to be predicted and analyzed. The project library module 2 matches the combustion parameters corresponding to the combustibles predicted to burn with the environmental parameters, because different substances have different property parameters under different environmental parameters (such as temperature), such as specific heat capacity at constant pressure, heat of vaporization, etc., and different parameters need to be matched before being brought into the formula for calculation. The project library module 2 is communicated with the calculation module 3; wherein, the combustion parameters include heat of combustion, specific heat capacity at constant pressure, boiling point and heat of vaporization. The heat of combustion refers to the energy released when 1 mole of a substance is completely burned to form a stable oxide under standard conditions (usually 25°C and 1 atmosphere). The specific heat capacity at constant pressure refers to the amount of heat required to absorb for each 1K increase in temperature of a unit mass of a substance under constant pressure. The heat of vaporization is the heat required to convert a unit mass of liquid into a gas under constant temperature and pressure.

[0023] The project includes the project name, project boundary and risk source location. The project boundary includes the geographical boundary, that is, the project area boundary, which is used to compare whether the fire risk prediction affects the environment outside the project area and sensitive targets.

[0024] Risk sources include technical risks, economic risks, human resource risks and external environmental risks. Technical risks include sensor failure, data transmission interruption and algorithm failure; economic risks include project overspending and capital chain breaks; human resource risks include the departure of key personnel and insufficient team skills; and external environmental risks include natural disasters.

[0025] The calculation module 3 is communicatively connected with the graphics drawing module 4, and the graphics drawing module 4 is communicatively connected with the output module 5. The calculation module 3 calculates the amount of carbon monoxide produced, the flame height h and the emission rate after the combustion of the combustion material through a preset formula. In this embodiment, carbon monoxide is taken as a risk substance, and the physical and chemical properties of carbon monoxide are automatically matched, wherein the physical and chemical properties of carbon monoxide include molecular weight, boiling point, density, saturated vapor pressure and toxicity concentration. The above parameters and the stability index Ri of the smoke puff are brought into the State Environmental Protection Key Laboratory of Numerical Simulation for Environmental Impact Assessment (SLAB) or AFTOX and other models, wherein the AFTOX (Air Force TOXicant) model is a computer simulation tool for evaluating the environmental impact of atmospheric pollutant emissions, the maximum toxic concentration and the farthest impact distance are calculated, and the maximum toxic concentration is compared with the atmospheric toxicity endpoint concentration. If it is greater than the atmospheric toxicity endpoint concentration, the graphics drawing module 4 draws the risk impact range map according to the farthest impact distance and outputs it through the output module 5; if it is less than the atmospheric toxicity endpoint concentration, the graphics drawing module 4 does not need to draw, and the output module 5 outputs a prediction analysis report, which includes risk level, process risk identification, risk material identification and risk prediction results, etc. The risk impact range map is part of the prediction analysis report. Among them, the atmospheric toxicity endpoint concentration refers to the concentration of atmospheric pollutants that may cause health effects or death to personnel in the short term. The setting of the atmospheric toxicity endpoint concentration is based on the study of the acute toxicity of pollutants to determine a threshold value. Under this threshold value, the exposed population will not suffer irreversible health damage or life threats in a short period of time (generally 1 hour).

[0026] Assuming the liquid pool is circular, the flame height h is calculated as: Where r is the radius of the liquid pool; dm / dt is the burning rate per unit surface area, kg / (m 2 .s); ρ0-air density; kg / m3; g-gravitational acceleration, m / s3 。

[0027] in,

[0028] Hc-heat of combustion of liquid, J / kg; Cp-specific heat capacity of liquid at constant pressure, J / (kg.k); Tb-boiling point of liquid, K; T0-ambient temperature, K; Hvap-heat of vaporization of liquid, J / kg.

[0029] Among them, when the combustion material is sulfur dioxide, the preset formula includes sulfur dioxide emission rate kg / h: G 二氧化硫 =2BS, B—combustion amount of substance, kg / h; S—sulfur content in substance, %. The sulfur content in substance is calculated based on the amount of substance in molecular formula.

[0030] When the combustion product is carbon monoxide, the preset formula includes the production of carbon monoxide kg / s: G 一氧化碳 =2330qCQ, C—carbon content in the substance, taken as 85%; q—chemical incomplete combustion value, taken as 1.5%-6.0%; Q—mass of substance participating in combustion, t / s.

[0031] The preset formula also includes the puff stability index Ri: It is a parameter used to measure the stability of the smoke puff relative to the surrounding environment. When Ri is large, it means that the smoke puff is relatively unstable and easily dispersed by turbulence; on the contrary, when Ri is small, it means that the smoke puff is relatively stable and not easily affected by turbulence.

[0032] Determining whether it is continuous emission or instantaneous emission can be determined by comparing the emission time Td and the time T when the pollutant reaches the nearest receptor point (grid point or sensitive point).

[0033] T=2X / Ur

[0034] Where X is the distance between the accident site and the calculation point, m;

[0035] Ur-10m height wind speed, m / s. Assume that wind speed and direction remain unchanged in the T time period. When Td>T, it is considered as continuous emission; when Td≤T, it can be considered as instantaneous emission.

[0036] When discharging continuously:

[0037] When instantaneous discharge occurs:

[0038] Where: rel - Initial density of the emitted substance entering the atmosphere, kg / m 3 ;

[0039] ρ a -Ambient air density, kg / m 3 ;

[0040] Q-emission rate of continuous emission plume, kg / s;

[0041] Qt-mass of substance emitted instantaneously, kg;

[0042] Drel-initial puff width, i.e. source diameter, m;

[0043] Ur-wind speed at 10m height, m / s.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fire environment prediction and analysis system, characterized in that: It includes input module, project library module, control module, graphics drawing module and output module; The input module is used to input the combustion materials predicted to be burned and the environmental parameters, and the input module is in communication connection with the project library module; The project library module has pre-stored items of combustion objects that need to be predicted and analyzed, and the project library module matches the combustion parameters corresponding to the combustion objects predicted to be burned with the environmental parameters, and the project library module is in communication connection with the calculation module; The calculation module is communicatively connected with the graphics drawing module, and the graphics drawing module is communicatively connected with the output module. The calculation module calculates the amount of carbon monoxide produced, the flame height and the emission rate after the combustion of the combustible material through a preset formula, and takes carbon monoxide as a risk substance, automatically matches the physical and chemical properties of carbon monoxide, calculates the maximum toxicity concentration and the farthest impact distance, and compares the maximum toxicity concentration with the atmospheric toxicity endpoint concentration. If it is greater than the atmospheric toxicity endpoint concentration, the graphics drawing module draws a risk impact range map according to the farthest impact distance and outputs it through the output module; if it is less than the atmospheric toxicity endpoint concentration, the graphics drawing module does not need to draw, and the output module outputs a prediction analysis report.

2. The fire environment prediction and analysis system according to claim 1, characterized in that: The environmental parameters include ambient temperature, liquid pool area and predicted extinguishing time.

3. The fire environment prediction and analysis system according to claim 1, characterized in that: The combustion parameters include heat of combustion, specific heat capacity at constant pressure, boiling point and heat of vaporization.

4. The fire environment prediction and analysis system according to claim 1, characterized in that: The pre-stored projects in the project library module include project names, project boundaries and risk source locations.

5. The fire environment prediction and analysis system according to claim 1, characterized in that: The preset formula includes sulfur dioxide emission rate kg / h: G 二氧化硫 =2BS, B—combustion amount of substance, kg / h; S—sulfur content in substance, %.

6. The fire environment prediction and analysis system according to claim 1, characterized in that: The preset formula also includes the amount of carbon monoxide produced kg / s: G 一氧化碳 =2330qCQ, C—carbon content in the substance, taken as 85%; q—chemical incomplete combustion value, taken as 1.5%-6.0%; Q—mass of substance participating in combustion, t / s.

7. The fire environment prediction and analysis system according to claim 6, characterized in that: The preset formula also includes the puff stability index Ri:

8. The fire environment prediction and analysis system according to claim 1, characterized in that: The physical and chemical properties of carbon monoxide include molecular weight, boiling point, density, saturated vapor pressure and toxic concentration.

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