CN111401715B - Aviation accurate fire extinguishing evaluation method and evaluation system thereof - Google Patents
Aviation accurate fire extinguishing evaluation method and evaluation system thereof Download PDFInfo
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Abstract
The application discloses an aviation accurate fire extinguishing evaluation method and an aviation accurate fire extinguishing evaluation system, wherein the method comprises the steps of acquiring internal parameters of an aviation fire extinguishing device and external parameters of a fire scene; calculating the landing dosage of the fire extinguishing agent in the unit area of the fire scene by combining the internal parameters and the external parameters; evaluating the fire extinguishing effect according to the landing dosage of the fire extinguishing agent in the unit area of the fire scene; and adjusting the internal parameters according to the fire extinguishing effect until the fire extinguishing effect is maximized. According to the application, the time for the fire extinguishing agent to fall to the ground is calculated by establishing a stress analysis model for the water agent to fall, so that the displacement of the fire extinguishing agent in the horizontal direction is further obtained; combining the interaction of the fire extinguishing agent and high-temperature air, and calculating the evaporation capacity of the fire extinguishing agent in the falling process; according to parameters such as mountain fire type, vegetation density, fire extinguishing agent concentration and the like, the shielding amount of the aviation fire extinguishing agent reaching a fire scene is calculated, so that the area and unit area dosage of the fire extinguishing agent falling to the fire scene are calculated, and the mountain fire extinguishing accuracy and effect of the power transmission line are improved.
Description
Technical Field
The application belongs to the technical field of forest fire prevention and control of power transmission lines, and particularly relates to an aviation accurate fire extinguishing evaluation method and an evaluation system thereof.
Background
In recent years, under the influence of continuous drought weather and production and living of residents nearby a power transmission line, forest fire accidents frequently occur in a power transmission line corridor, and the safe and stable operation of a power grid is seriously threatened. The helicopter is adopted to extinguish fire, so that the helicopter is not limited by external conditions such as road blockage and the like, and can quickly reach a fire scene to extinguish fire. However, the mountain fire scene environment of the power transmission line is complex, the fire extinguishing agent for aviation fire extinguishment depends on pilot experience, but factors such as scene wind speed, scene smoke plume speed, scene temperature and the like have great influence on the accuracy of the fire extinguishing agent, and a large amount of fire extinguishing agent is wasted due to low-accuracy fire extinguishment. Meanwhile, the mountain fire site temperature of the power transmission line is high, and the evaporation capacity of the fire extinguishing agent reaches 60% -80% in the falling process, so that the mountain fire aviation fire extinguishing evaluation of the power transmission line is carried out, and the evaporation capacity of the fire extinguishing agent must be considered. In addition, on-site vegetation is dense, and when the fire extinguishing agent is sprayed to the top combustible, the fire extinguishing agent possibly cannot reach the surface combustible, and factors such as flow characteristics, vegetation density and the like after the fire extinguishing agent reaches a fire scene are also key factors influencing the forest fire extinguishing effect of the power transmission line. Therefore, in most cases, the fire extinguishing experience of pilots is very different from the fire extinguishing site, so that the fire extinguishing flow has to be increased in order to achieve the purpose of fire extinguishing, so that the fire extinguishing flow is particularly large, a large amount of fire extinguishing water agent is wasted, and the fire extinguishing system is a waste of a large amount of manpower and material resources for aviation fire extinguishing with precious load space. In addition, the fire extinguishing effect of the aviation fire extinguishing device needs to be adjusted along with the fire scene state, and instruction basis is needed. Therefore, an aviation accurate fire extinguishing calculation method is urgently needed.
At present, no aviation fire extinguishing guidance method exists.
Disclosure of Invention
The application aims to provide an aviation accurate fire extinguishing evaluation method and an aviation accurate fire extinguishing evaluation system, which are used for solving the technical defects in the prior art.
In order to achieve the above purpose, the application provides an aviation accurate fire extinguishing evaluation method, which comprises the following steps:
acquiring internal parameters of the aviation fire extinguishing device and external parameters of a fire scene;
calculating the landing dosage of the fire extinguishing agent in the unit area of the fire scene by combining the internal parameters and the external parameters;
evaluating the fire extinguishing effect according to the landing dosage of the fire extinguishing agent in the unit area of the fire scene;
preferably, the internal parameters include the ejection speed of the fire extinguishing agent, the flow rate of the fire extinguishing agent, the proportion of the fire extinguishing agent, the flying speed of the aviation fire extinguishing device and the number of nozzles of the aviation fire extinguishing device, and the external parameters include the fire scene wind speed, the fire scene wind direction, the fire scene temperature and the vegetation type.
Preferably, calculating the landing dosage of the fire extinguishing agent in the unit area of the fire scene by combining the internal parameter and the external parameter comprises the following steps:
calculating the speed and acceleration of the fire extinguishing agent at different heights and different times according to the ejection speed of the fire extinguishing agent and the wind speed of a fire scene;
calculating the total evaporation amount of the fire extinguishing agent in the falling process according to the ambient temperature, the contact area of the fire extinguishing agent, the dispersion state of the fire extinguishing agent and the evaporation latent heat of the fire extinguishing agent; calculating the drifting total amount of the fire extinguishing agent which does not fall into a forest fire area in the falling process according to the speeds and accelerations of the fire extinguishing agent at different heights and at different times; calculating to obtain the shielded quantity of the fire extinguishing agent according to the vegetation type of the fire scene, the flow rate and the evaporation total quantity of the fire extinguishing agent;
and calculating the landing dosage of the fire extinguishing agent in the unit area of the fire scene according to the flow rate of the fire extinguishing agent, the evaporation total amount of the fire extinguishing agent, the drifting total amount of the fire extinguishing agent and the shielded amount of the fire extinguishing agent.
Preferably, the speed and acceleration calculation method of the fire extinguishing agent at different heights and different times comprises the following steps:
decomposing the injection speed of the fire extinguishing agent into horizontal speedAnd vertical speed->The method comprises the steps of carrying out a first treatment on the surface of the The wind speed of the fire scene is decomposed into horizontal wind speed->And vertical plume velocity +>；
Divide into two-layer with fire extinguishing agent, be projection cone angle layer and projection rectangle layer respectively, wherein, the acceleration and the speed that projection cone angle layer horizontal wind speed acted on fire extinguishing agent are:
in the method, in the process of the application,the air resistance coefficient is 0.5-1.0%>Is the diameter of the bottom round surface of the cone angle layer, +.>For the horizontal velocity of the extinguishing agent at the end of the projection cone angle layer, < >>For air density->Is the density of the fire extinguishing agent;
the acceleration and the speed of the horizontal wind speed of the projected rectangular layer acting on the fire extinguishing agent are as follows:
in the method, in the process of the application,side length of bottom square of projected rectangular layer, +.>The horizontal speed of the fire extinguishing agent at the tail end of the projected rectangular layer;
the wind resistance in the vertical direction of the projection cone angle layer and the acceleration and the speed of gravity acting on the water body are as follows:
wherein the vertical wind resistance of the projection cone angle layer is as follows:
in the method, in the process of the application,for the vertical height of the projection cone angle layer, +.>Is a fire extinguishing agentVertical speed (vertical speed)>Acceleration of gravity, ++>Is an air resistance coefficient, wherein the air resistance coefficient is +.>Related to the reynolds number of the fluid:
for a characteristic length linked to the cross-sectional area of the object, +.>For fluid density->As the viscosity of the fluid, then:
thereby calculating and obtaining the wind resistance in the vertical direction of the projection cone angle layer and the acceleration and the speed of gravity acting on the water body;
the wind resistance of the projected rectangular layer in the vertical direction and the acceleration and speed of gravity acting on the water body are as follows:
wherein the vertical wind resistance of the projected rectangular layer is:
then:
thereby calculating the wind resistance in the vertical direction of the projected rectangular layer and the acceleration and the speed of gravity acting on the water body.
Preferably, the total evaporation amount of the fire extinguishing agent in the falling process is calculated according to an evaporation model, wherein the evaporation model is as follows:
below the water level of the fire extinguishing agent, namely，/>：
In a water body of fire-extinguishing agent, i.e，/>：
Above the water level of the fire extinguishing agent, i.e，/>：
In the method, in the process of the application,，/>wherein->For time (I)>For life cycle of fire extinguishing agent>For the temperature of the fire scene>Is the heat conduction coefficient of the fire extinguishing agent +.>，/>Is the heat conductivity of the fire extinguishing agent>Is the specific heat capacity of the fire extinguishing agent.
Preferably, the method for calculating the shielded quantity of the fire extinguishing agent according to the vegetation type of the fire scene, the flow quantity of the fire extinguishing agent and the evaporation total quantity comprises the following steps:
acquiring vegetation types, including shielding coefficients corresponding to the vegetation types and vegetation space density;
calculating the shielded quantity according to the shielding coefficient, the vegetation space density, the evaporation total quantity and the proportion of the fire extinguishing agent:
in the method, in the process of the application,for shading coefficient->For the flow of fire extinguishing agent->The mixture ratio of the fire extinguishing agent is->For evaporating total amount->Is vegetation space density->Takes the value of +.>。
Preferably, before the floor dosage of the fire extinguishing agent is calculated, the horizontal displacement of the fire extinguishing agent is required to be determined, and the calculation mode of the horizontal displacement of the fire extinguishing agent is as follows:
the whole area is regarded as the length of the water bandAnd diameter of circular area>A rectangular region formed;
length of water bandIs the straight-line driving distance of the aviation fire extinguishing device in the whole water throwing process +.>Diffusion radius +.about.of water body at moment of starting and ending water throwing in helicopter sailing direction>The sum is that:
wherein the straight-line driving distance of the aviation fire extinguishing device in the water throwing processThe method comprises the following steps:
in the method, in the process of the application,for the flying speed of the aviation fire extinguishing device, +.>Wind speed is>Wind direction, the->For the course correction value,the time for throwing water for the fire-extinguishing helicopter, wherein ++>，/>The number of the nozzles.
Preferably, the floor dosage of the fire extinguishing agent is:
in the method, in the process of the application,for water dosage, add->Is the water throwing area, wherein,
。
preferably, the Reynolds number。
The application also discloses an aviation accurate fire extinguishing evaluation system which comprises a processor, a memory and a computer program stored on the memory, wherein the processor realizes any one of the methods when executing the computer program.
The application has the following beneficial effects:
according to the application, the horizontal displacement of the fire extinguishing agent is accurately calculated by taking the flight speed of the aviation fire extinguishing device and the acceleration vector sum of the fire extinguishing agent under the action of on-site environmental wind and fire scene smoke plumes into consideration; the contact area and the evaporation capacity of the fire extinguishing agent under different fire scene temperatures are calculated, so that the fire extinguishing agent dosage of the mountain fire unit area of the power transmission line is accurately obtained, and an evaluation basis is provided for fire extinguishment of an aviation helicopter.
The application will be described in further detail with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the application. In the drawings:
FIG. 1 is a schematic illustration of an aerial fire suppression device according to a preferred embodiment of the present application;
fig. 2 is a schematic view of a position scale of the fire extinguishing agent in the falling process according to the preferred embodiment of the present application;
fig. 3 is a schematic illustration of an aviation precise fire extinguishing method and a fire extinguishing system according to a preferred embodiment of the present application.
Detailed Description
Embodiments of the application are described in detail below with reference to the attached drawings, but the application can be implemented in a number of different ways, which are defined and covered by the claims.
The application firstly provides an aviation accurate fire extinguishing evaluation method, which is shown in fig. 3 and comprises the following steps:
s1: acquiring internal parameters of the aviation fire extinguishing device and external parameters of a fire scene.
The internal parameters comprise the ejection speed of the fire extinguishing agent, the flow rate of the fire extinguishing agent, the proportion of the fire extinguishing agent, the flight speed of the aviation fire extinguishing device and the number of nozzles of the aviation fire extinguishing device, and the external parameters comprise the fire scene wind speed, the fire scene wind direction, the fire scene temperature and the vegetation type.
Referring to fig. 1, the present embodiment assumes that the fire-extinguishing agent is uniformly sprayed from the water outlet at a certain initial velocity. When Reynolds numberThe jet is a turbulent jet, and the value range of Reynolds number is +.>. Therefore, the Reynolds number +.>Set to be greater than 30. The injection speed of the fire extinguishing agent can be decomposed into horizontal speed +.>And vertical speed->The method comprises the steps of carrying out a first treatment on the surface of the The wind speed of the fire scene can be decomposed into horizontal wind speed +.>And vertical plume velocity +>The method comprises the steps of carrying out a first treatment on the surface of the The temperature of the fire scene can be obtained by measuring the ambient temperature at the height of the aviation fire extinguishing device and then by correction calculation. The obtained fire temperature includes the fire temperature at each level of the fire. Furthermore, the flying pitch angle of the aerial fire device may also be obtained directly from the aerial fire device or from a remote system in communication therewith.
S2: and calculating the landing dosage of the fire extinguishing agent in the unit area of the fire scene by combining the internal parameters and the external parameters.
The landing dosage of the fire extinguishing agent is a key factor for evaluating the fire extinguishing effect, so that the landing dosage of the fire extinguishing agent in the unit area of a fire scene needs to be calculated. The method comprises the following steps:
s21: and calculating the speed and acceleration of the fire extinguishing agent at different heights and different times according to the ejection speed of the fire extinguishing agent and the wind speed of a fire scene.
The method comprises the steps of calculating the stress of the fire extinguishing agent according to the wind speed of the site environment, and obtaining the acceleration and the speed of the water body in the horizontal and vertical directions at different heights and different time points.
Divide into two-layer with fire extinguishing agent, be projection cone angle layer and projection rectangle layer respectively, wherein, the acceleration and the speed that projection cone angle layer horizontal wind speed acted on fire extinguishing agent are:
in the method, in the process of the application,the air resistance coefficient is 0.5-1.0%>Is the diameter of the bottom round surface of the cone angle layer, +.>For the horizontal velocity of the extinguishing agent at the end of the projection cone angle layer, < >>For air density->Is the density of the fire extinguishing agent;
the acceleration and the speed of the horizontal wind speed of the projected rectangular layer acting on the fire extinguishing agent are as follows:
in the method, in the process of the application,side length of bottom square of projected rectangular layer, +.>The horizontal speed of the fire extinguishing agent at the tail end of the projected rectangular layer;
the wind resistance in the vertical direction of the projection cone angle layer and the acceleration and the speed of gravity acting on the water body are as follows:
wherein the vertical wind resistance of the projection cone angle layer is as follows:
in the method, in the process of the application,for the vertical height of the projection cone angle layer, +.>For the vertical velocity of the fire suppression agent at the end of the projected rectangular layer,acceleration of gravity, ++>Is an air resistance coefficient, wherein the air resistance coefficient is +.>Related to the reynolds number of the fluid:
for a characteristic length linked to the cross-sectional area of the object, +.>For fluid density->As the viscosity of the fluid, then:
thereby calculating and obtaining the wind resistance in the vertical direction of the projection cone angle layer and the acceleration and the speed of gravity acting on the water body;
the wind resistance of the projected rectangular layer in the vertical direction and the acceleration and speed of gravity acting on the water body are as follows:
wherein the vertical wind resistance of the projected rectangular layer is:
then:
thereby calculating the acceleration and the speed of the vertical wind resistance of the projected rectangular layer and the gravity acting on the extinguishing agent,is the vertical speed of the fire extinguishing agent at the end of the projected rectangular layer.
The acceleration and the speed of the natural wind of the projection cone angle layer acting on the extinguishing agent of the projection cone angle layer are the acceleration and the speed of the extinguishing agent; similarly, the acceleration and the speed of the natural wind of the projected rectangular layer acting on the fire extinguishing agent are the acceleration and the speed of the fire extinguishing agent of the projected rectangular layer.
The falling time of the fire extinguishing agent can be calculated according to the acceleration and the speed of the fire extinguishing agent.
In calculating the falling time, the coverage area is reduced to a circular area with the center falling point as the center and the average distance of the center falling point from the boundary as the radius.
S22: calculating the total evaporation amount of the fire extinguishing agent in the falling process according to the ambient temperature, the contact area of the fire extinguishing agent, the dispersion state of the fire extinguishing agent and the evaporation latent heat of the fire extinguishing agent; calculating the drifting total amount of the fire extinguishing agent which does not fall into a forest fire area in the falling process according to the speeds and accelerations of the fire extinguishing agent at different heights and at different times; and calculating the shielded quantity of the fire extinguishing agent according to the vegetation type of the fire scene, the flow quantity of the fire extinguishing agent and the evaporation total quantity.
The dispersion state of the fire extinguishing agent is defined as the cone angle of the projection cone angle layerThe method comprises the steps of carrying out a first treatment on the surface of the The contact area of the fire extinguishing agent is +.>Surface area of the projected rectangular layer +.>Wherein->For projection cone angle layer cone height, +.>The height of the rectangular layer cuboid is projected; the evaporation latent heat of the fire-extinguishing water agent is an inherent property of the fire-extinguishing water agent, and when the formula and the proportion of the fire-extinguishing water agent are determinedThe latent heat of evaporation is also determined at this time, and can be determined by ordinary physical methods before addition.
S221: and calculating the total evaporation amount of the fire extinguishing agent in the falling process according to the ambient temperature, the contact area of the fire extinguishing agent, the dispersion state of the fire extinguishing agent and the evaporation latent heat of the fire extinguishing agent.
The method for calculating the evaporation capacity of the fire extinguishing agent in the falling process is as follows:
temperature distribution at different heights according to fire sceneThe contact area of the fire-extinguishing agent, the dispersion state of the fire-extinguishing agent and the evaporation latent heat of the fire-extinguishing agent, the evaporation capacity of the fire-extinguishing agent at different heights is calculated, and the evaporation total capacity of the fire-extinguishing agent in the falling process is calculated by adopting an integration method>. The evaporation total amount of the fire extinguishing agent in the falling process is calculated according to an evaporation model.
Referring to fig. 2, it is assumed that the water body is divided into 2 stages during the falling process, the 1 st stage is an overall water column stage, the 2 nd stage is a scattering water body stage, wherein the scattering water body in the 2 nd stage is divided into 10 stages according to the diameter of the water drops.
The evaporation model is then:
below the height of the fire extinguishing agent，/>：
In fire-extinguishing water, i.e. in，/>：
Above the height of the fire extinguishing agent，/>：
In the method, in the process of the application,，/>wherein->For time (I)>For life cycle of fire extinguishing agent>For the temperature of the fire scene>Is the heat conduction coefficient of the fire extinguishing agent +.>，/>Is the heat conductivity of the fire extinguishing agent>To be turned offSpecific heat capacity of the fire water agent.
The application considers that evaporation only occurs on the surface of the water body, and therefore, the evaporation surface is a conical surface in the stage of integral water column and three rectangular surfaces in the stage of scattering the water body.
Boundary conditions:
in the water column stage:
for the evaporation heat absorption (J/kg) of extinguishing agent, -for extinguishing agent>Is the evaporation rate of the fire extinguishing agent. />Is the falling speed of the fire extinguishing agent.
S222: and calculating the drifting total amount of the fire extinguishing agent which does not fall into the forest fire area in the falling process according to the speeds and the accelerations of the fire extinguishing agent at different heights and at different times.
According to the integral and the speed of the acceleration of the fire extinguishing agent in the horizontal direction, the horizontal displacement of the fire extinguishing agent is obtained by adopting an integral method, and the area of the fire extinguishing agent reaching the ground is drawn, wherein the fire extinguishing dose which does not fall into the mountain fire burning area is the drift amount。
When calculating the horizontal displacement, the whole area is regarded as the length of the water bandAnd diameter of circular area>A rectangular region formed;
length of water bandIs the straight-line driving distance of the aviation fire extinguishing device in the whole water throwing process +.>Diffusion radius of fire extinguishing agent in helicopter sailing direction at moment of starting and ending water throwing +.>The sum is that:
wherein the straight-line driving distance of the aviation fire extinguishing device in the water throwing processThe method comprises the following steps:
in the method, in the process of the application,for the flying speed of the aviation fire extinguishing device, +.>Wind speed is>Wind direction, the->For the course correction value,the time for throwing water for the fire-extinguishing helicopter, wherein ++>，/>Namely, the initial spraying speed of the fire extinguishing water agent is the square sum of the horizontal initial speed and the vertical initial speed, and the root opening number is +.>The number of the nozzles.
S223: calculating the shielded quantity of the fire extinguishing agent according to the vegetation type of the fire scene, the flow rate and the evaporation total quantity of the fire extinguishing agent
Calculating the shielding amount of the fire extinguishing agent according to the type of mountain fire vegetation, the vegetation transmission coefficient, the type of mountain fire, the viscosity and the concentration of the fire extinguishing agent of the power transmission line
S2231: and obtaining vegetation types, wherein the vegetation types comprise shading coefficients corresponding to the vegetation types and vegetation space density.
The vegetation combustible species in the mountain fire scene of the power transmission line are numerous, and the vegetation type, the mountain fire type and the fire extinguishing water agent parameter are required to be calculated in a classified mode. Table 1 below shows the fire shielding factorA distribution table.
Table 1 fire field shading coefficient of aeronautical fire extinguishing device
S2232: and calculating the shielded quantity according to the shielding coefficient, the vegetation space density, the evaporation total quantity and the proportion of the fire extinguishing agent.
The fire extinguishing agent is prepared fromAccording to the total evaporation amount, the concentration of the fire-extinguishing agent when the fire-extinguishing agent reaches the vegetation combustible is obtained to be +.>
As the concentration of the fire-extinguishing agent increases, the viscosity of the fire-extinguishing agent increases, so that the fluidity of the fire-extinguishing agent decreases, and the more the fire-extinguishing agent is shielded. Experiments show that the concentration and the viscosity of the fire extinguishing agent are in direct proportion, so that the concentration of the fire extinguishing agent in the fire extinguishing agent is directly used as a key parameter for calculating the shielding amount.
Although the fire extinguishing agent has fluidity, when the shielding density of the vegetation combustible is large, the blocking effect on the fire extinguishing agent is increased, so that the fire extinguishing agent cannot reach the burning area of a fire scene at the same time, and the fire extinguishing effect is reduced. Thus, the application uses the space density of the field combustibleAs a influencing factor influencing the shielding amount of the extinguishing agent.
In the method, in the process of the application,for shading coefficient->For the flow of fire extinguishing agent->The mixture ratio of the fire extinguishing agent is->For evaporating total amount->Is vegetation space density->Takes the value of +.>。
S23: and calculating the landing dosage of the fire extinguishing agent in the unit area of the fire scene according to the flow rate of the fire extinguishing agent, the evaporation total amount of the fire extinguishing agent, the drifting total amount of the fire extinguishing agent and the shielded amount of the fire extinguishing agent.
According to the flow rate of the aviation fire extinguishing deviceDrift amount->And evaporation amount->Calculating the effective fire extinguishing dose of the fire extinguishing agent reaching the ground>。
S3: and evaluating the fire extinguishing effect according to the landing dosage of the fire extinguishing agent in the unit area of the fire scene.
Crossing area of area where fire extinguishing agent reaches ground and actual mountain fire combustion area of power transmission lineIn an effective extinguishing dose +.>Divided by the cross-over area->And obtaining the sprinkling dose of the unit area of the fire scene.
The floor dosage of the fire extinguishing agent is as follows:
in the method, in the process of the application,for water dosage, add->Is the water throwing area, wherein,
。
s4: and adjusting internal parameters according to the fire extinguishing effect until the fire extinguishing effect is maximized.
The application also discloses an aviation accurate fire extinguishing evaluation system which comprises a processor, a memory and a computer program stored on the memory, wherein the processor realizes any one of the methods when executing the computer program.
According to the application, the time for the fire extinguishing agent to fall to the ground is calculated by establishing a stress analysis model for the falling of the fire extinguishing agent of the aviation fire extinguishing device, so that the displacement of the fire extinguishing agent in the horizontal direction is further obtained; combining the interaction of the fire extinguishing agent and high-temperature air, and calculating the evaporation capacity of the fire extinguishing agent in the falling process; and calculating the shielding amount of the aviation fire-extinguishing agent reaching the fire scene according to parameters such as the mountain fire type, vegetation density, fire extinguishing agent concentration and the like of the mountain fire scene of the power transmission line. On the basis, the area and unit area dosage of the fire extinguishing agent falling to a fire scene are calculated, and the accuracy and effect of mountain fire extinguishment of the power transmission line are improved.
The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.
Claims (7)
1. The aviation accurate fire extinguishing evaluation method is characterized by comprising the following steps of:
acquiring internal parameters of the aviation fire extinguishing device and external parameters of a fire scene;
calculating the landing dosage of the fire extinguishing agent in the unit area of the fire scene by combining the internal parameters and the external parameters;
evaluating the fire extinguishing effect according to the landing dosage of the fire extinguishing agent in the unit area of the fire scene;
the internal parameters comprise the ejection speed of the fire extinguishing agent, the flow rate of the fire extinguishing agent, the proportion of the fire extinguishing agent, the flight speed of the aviation fire extinguishing device and the number of nozzles of the aviation fire extinguishing device, and the external parameters comprise the fire scene wind speed, the fire scene wind direction, the fire scene temperature and the vegetation type;
the step of calculating the floor dosage of the fire extinguishing agent in the unit area of the fire scene by combining the internal parameters and the external parameters comprises the following steps:
calculating the speed and acceleration of the fire extinguishing agent at different heights and different times according to the ejection speed of the fire extinguishing agent and the wind speed of a fire scene;
calculating the total evaporation amount of the fire extinguishing agent in the falling process according to the environment temperature of the aviation fire extinguishing device, the dispersion state of the fire extinguishing agent, the contact area of the fire extinguishing agent and the evaporation latent heat of the fire extinguishing agent; calculating the drifting total amount of the fire extinguishing agent which does not fall into a forest fire area in the falling process according to the speeds and accelerations of the fire extinguishing agent at different heights and at different times; calculating to obtain the utilization amount of the fire extinguishing agent according to the vegetation type of the fire scene, the flow rate of the fire extinguishing agent and the evaporation total amount;
according to the flow rate of the fire-extinguishing agent, the evaporation total amount of the fire-extinguishing agent, the drifting total amount of the fire-extinguishing agent and the utilization amount of the fire-extinguishing agent, the landing dosage of the fire-extinguishing agent in the unit area of a fire scene is calculated;
the total evaporation amount of the fire extinguishing agent in the falling process is calculated according to an evaporation model, wherein the evaporation model is as follows:
below the water level of the fire extinguishing agent, namely，/>：
In a water body of fire-extinguishing agent, i.e， />：
Above the water level of the fire extinguishing agent, i.e， />：
In the method, in the process of the application,，/>wherein->For time (I)>For life cycle of fire extinguishing agent>For the temperature of the fire scene>Is the heat conduction coefficient of the fire extinguishing agent +.>，/>Is the heat conductivity of the fire extinguishing agent>To achieve the specific heat capacity of the fire extinguishing agent,is the density of the fire extinguishing agent.
2. The method for evaluating the precise fire extinguishing of the aviation according to claim 1, wherein the method for calculating the speed and the acceleration of the fire extinguishing agent at different heights and different times is as follows:
decomposing the injection speed of the fire extinguishing agent into horizontal speedAnd vertical speed->The method comprises the steps of carrying out a first treatment on the surface of the The wind speed of the fire scene is decomposed into horizontal wind speedAnd vertical plume velocity +>；
Dividing the fire extinguishing agent into two layers, namely a projection cone angle layer and a projection rectangular layer, wherein the horizontal wind speed of the projection cone angle layer acts on the acceleration of the fire extinguishing agentAnd speed->The method comprises the following steps:
in the method, in the process of the application,the air resistance coefficient is 0.5-1.0%>Is the diameter of the bottom round surface of the cone angle layer, +.>For the horizontal velocity of the extinguishing agent at the end of the projection cone angle layer, < >>For air density->Is the density of the fire extinguishing agent;
acceleration of horizontal wind speed of projected rectangular layer acting on fire extinguishing agentAnd speed->The method comprises the following steps:
in the method, in the process of the application,side length of bottom square of projected rectangular layer, +.>The horizontal speed of the fire extinguishing agent at the tail end of the projected rectangular layer;
wind resistance in vertical direction of projection cone angle layer and acceleration of gravity acting on water bodyAnd speed->The method comprises the following steps:
wherein the vertical wind resistance of the projection cone angle layer is as follows:
in the method, in the process of the application,for the vertical height of the projection cone angle layer, +.>For the vertical speed of the fire extinguishing agent at the end of the projection cone angle layer, < >>Acceleration of gravity, ++>Is an air resistance coefficient, wherein the air resistance coefficient is +.>Reynolds number of fluid->The following are related:
for a characteristic length linked to the cross-sectional area of the object, +.>For fluid density->As the viscosity of the fluid, then:
thereby calculating and obtaining the wind resistance in the vertical direction of the projection cone angle layer and the acceleration of gravity acting on the water bodyAnd speed->；
Wind resistance in vertical direction of projected rectangular layer and acceleration of gravity acting on water bodyAnd speed->The method comprises the following steps:
wherein the vertical wind resistance of the projected rectangular layer is:
then:
thereby calculating and obtaining the wind resistance of the projected rectangular layer in the vertical direction and the acceleration of gravity acting on the water bodyAnd speed->，/>Is the vertical speed of the fire extinguishing agent at the end of the projected rectangular layer.
3. The method for evaluating the aviation precision fire extinguishing according to claim 1, wherein the fire extinguishing agent utilization amount calculated according to the fire scene vegetation type, the flow rate of the fire extinguishing agent and the evaporation total amount comprises the following steps:
acquiring vegetation types, including shielding coefficients corresponding to the vegetation types and vegetation space density;
calculating the utilization amount of the fire extinguishing agent according to the shielding coefficient, the vegetation space density, the evaporation total amount and the proportion of the fire extinguishing agent:
in the method, in the process of the application,for shading coefficient->For the flow of fire extinguishing agent->The mixture ratio of the fire extinguishing agent is->For evaporating total amount->Is vegetation space density->Takes the value of +.>。
4. The method for evaluating the precise fire extinguishing of the aviation according to claim 1, wherein the horizontal displacement of the fire extinguishing agent is required to be determined before the floor dosage of the fire extinguishing agent is calculated, and the calculation mode of the horizontal displacement of the fire extinguishing agent is as follows:
the whole area is regarded as the length of the water bandAnd diameter of circular area>A rectangular region formed;
length of water bandIs the straight-line driving distance of the aviation fire extinguishing device in the whole water throwing process +.>Diffusion radius +.about.of water body at moment of starting and ending water throwing in helicopter sailing direction>The sum is that:
wherein the straight-line driving distance of the aviation fire extinguishing device in the water throwing processThe method comprises the following steps:
in the method, in the process of the application,for the flying speed of the aviation fire extinguishing device, +.>Wind speed is>Wind direction, the->For course correction value->The time for throwing water for the fire-extinguishing helicopter, wherein ++>，/>The initial spraying speed of the fire extinguishing agent is horizontal initial speed +.>And vertical initial speed +.>Sum of squaresRoot number of JavaScript>For the number of spouts>Is the water feeding amount.
5. The method for evaluating the precise fire extinguishing of aviation according to claim 4, wherein the landing dosage of the fire extinguishing agent is:
in the method, in the process of the application,for water dosage, add->Is the water throwing area, wherein->。
6. An aviation accurate fire suppression assessment method according to claim 2, characterized in that said reynolds number。
7. An aviation precision fire extinguishing evaluation system comprising a processor, a memory and a computer program stored on said memory, characterized in that the processor implements the method according to any of claims 1-6 when executing said computer program.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000334057A (en) * | 1999-03-19 | 2000-12-05 | Fujitsu Fip Corp | Tree accumulation system and storage medium |
| CN101927068A (en) * | 2010-07-05 | 2010-12-29 | 中国航空无线电电子研究所 | Airline extinguishment auxiliary device and airline extinguishment method |
| CN109045541A (en) * | 2018-06-22 | 2018-12-21 | 国网湖南省电力有限公司 | Overcome unmanned plane extinguishing device control method, system and the storage medium of scene of a fire plume stream |
| RU190538U1 (en) * | 2019-03-27 | 2019-07-03 | Общество С Ограниченной Ответственностью Нпо "Современные Пожарные Технологии" | Device for preventing and extinguishing forest, industrial and emergency transport fires and laying of barrier strips with air-mechanical foam |
| CN110755769A (en) * | 2019-10-30 | 2020-02-07 | 湖南省湘电试研技术有限公司 | Helicopter fire extinguishing system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20100036549A1 (en) * | 2008-07-18 | 2010-02-11 | Honeywell International Inc. | Methods and systems for displaying a predicted distribution of fire retardant material from an aircraft |
-
2020
- 2020-03-10 CN CN202010160985.XA patent/CN111401715B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2000334057A (en) * | 1999-03-19 | 2000-12-05 | Fujitsu Fip Corp | Tree accumulation system and storage medium |
| CN101927068A (en) * | 2010-07-05 | 2010-12-29 | 中国航空无线电电子研究所 | Airline extinguishment auxiliary device and airline extinguishment method |
| CN109045541A (en) * | 2018-06-22 | 2018-12-21 | 国网湖南省电力有限公司 | Overcome unmanned plane extinguishing device control method, system and the storage medium of scene of a fire plume stream |
| RU190538U1 (en) * | 2019-03-27 | 2019-07-03 | Общество С Ограниченной Ответственностью Нпо "Современные Пожарные Технологии" | Device for preventing and extinguishing forest, industrial and emergency transport fires and laying of barrier strips with air-mechanical foam |
| CN110755769A (en) * | 2019-10-30 | 2020-02-07 | 湖南省湘电试研技术有限公司 | Helicopter fire extinguishing system |
Non-Patent Citations (5)
| Title |
|---|
| Olga V. Vysokomornaya et al..Experimental investigation of atomized water droplet initial parameters influence on evaporation intensity in flaming combustion zone.Fire Safety Journal.2014,第70卷第61-70页. * |
| 周特军.输电线路山火无人机监测与灭火技术研究.消防科学与技术.2020,第39卷(第2期),第239-242页. * |
| 孙迎春 等.基础物理实验.东北师范大学出版社,2015,第104-113页. * |
| 徐文祥 ; 袁健威 ; .高压细水雾不同空间位置灭火效果的数值模拟.农村经济与科技.2017,(13),第274-275页. * |
| 王永亮.大型灭火飞机投水算法研究.中国优秀硕士学位论文全文数据库（工程科技Ⅱ辑）.2013,(第1期),C031-56 11-27页. * |
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