CN111401715A - Aviation accurate fire extinguishing assessment method and assessment system thereof - Google Patents

Aviation accurate fire extinguishing assessment method and assessment system thereof Download PDF

Info

Publication number
CN111401715A
CN111401715A CN202010160985.XA CN202010160985A CN111401715A CN 111401715 A CN111401715 A CN 111401715A CN 202010160985 A CN202010160985 A CN 202010160985A CN 111401715 A CN111401715 A CN 111401715A
Authority
CN
China
Prior art keywords
fire extinguishing
agent
fire
water
speed
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202010160985.XA
Other languages
Chinese (zh)
Other versions
CN111401715B (en
Inventor
周特军
吴传平
刘毓
潘碧宸
陈宝辉
周天念
孙易成
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
State Grid Corp of China SGCC
State Grid Hunan Electric Power Co Ltd
Disaster Prevention and Mitigation Center of State Grid Hunan Electric Power Co Ltd
Original Assignee
State Grid Corp of China SGCC
State Grid Hunan Electric Power Co Ltd
Disaster Prevention and Mitigation Center of State Grid Hunan Electric Power Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by State Grid Corp of China SGCC, State Grid Hunan Electric Power Co Ltd, Disaster Prevention and Mitigation Center of State Grid Hunan Electric Power Co Ltd filed Critical State Grid Corp of China SGCC
Priority to CN202010160985.XA priority Critical patent/CN111401715B/en
Publication of CN111401715A publication Critical patent/CN111401715A/en
Application granted granted Critical
Publication of CN111401715B publication Critical patent/CN111401715B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q10/00—Administration; Management
    • G06Q10/06—Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
    • G06Q10/063—Operations research, analysis or management
    • G06Q10/0639—Performance analysis of employees; Performance analysis of enterprise or organisation operations
    • G06Q10/06393—Score-carding, benchmarking or key performance indicator [KPI] analysis
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
    • G06Q50/00—Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
    • G06Q50/10—Services
    • G06Q50/26—Government or public services

Landscapes

  • Business, Economics & Management (AREA)
  • Human Resources & Organizations (AREA)
  • Engineering & Computer Science (AREA)
  • Strategic Management (AREA)
  • Educational Administration (AREA)
  • Economics (AREA)
  • Development Economics (AREA)
  • Tourism & Hospitality (AREA)
  • General Business, Economics & Management (AREA)
  • Marketing (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Entrepreneurship & Innovation (AREA)
  • Primary Health Care (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Game Theory and Decision Science (AREA)
  • Operations Research (AREA)
  • Quality & Reliability (AREA)
  • Fire-Extinguishing By Fire Departments, And Fire-Extinguishing Equipment And Control Thereof (AREA)

Abstract

The invention discloses an aviation accurate fire extinguishing assessment method and an assessment system thereof, which comprises the steps of obtaining internal parameters of an aviation fire extinguishing device and external parameters of a fire scene; calculating the falling dosage of the fire extinguishing water agent in the unit area of the fire scene by integrating the internal parameters and the external parameters; evaluating the fire extinguishing effect according to the falling 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 invention, by establishing a stress analysis model of the drop of the water agent, the time of the fire extinguishing water agent dropping to the ground is calculated, and the displacement of the fire extinguishing water agent in the horizontal direction is further obtained; calculating the evaporation capacity of the fire extinguishing water agent in the falling process by combining the interaction of the fire extinguishing water agent and high-temperature air; according to the parameters such as the type of the forest fire, the vegetation density, the concentration of the fire extinguishing agent and the like, the shielding amount of the aerial fire extinguishing agent reaching the 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 accuracy and the effect of the forest fire extinguishing of the power transmission line are improved.

Description

Aviation accurate fire extinguishing assessment method and assessment system thereof
Technical Field
The invention belongs to the technical field of forest fire prevention and control of power transmission lines, and particularly relates to an aviation accurate fire extinguishing assessment method and an assessment system thereof.
Background
In recent years, due to the influence of continuous drought weather and production and life of residents nearby an electric transmission line, the frequent occurrence of mountain fire accidents in a corridor of the electric transmission line seriously threatens the safe and stable operation of a power grid. The helicopter is adopted for fire extinguishing, so that the helicopter is not limited by external conditions such as ground road blockage and the like, and can quickly reach a fire scene for fire extinguishing. However, the mountain fire field environment of the power transmission line is complex, the fire extinguishing water agent for aviation fire extinguishment depends on the experience of a pilot, but factors such as field wind speed, fire field smoke plume speed and fire field temperature have great influence on the accuracy of the fire extinguishing water agent, and low-accuracy fire extinguishment wastes a large amount of fire extinguishing water agent. Meanwhile, the temperature of the forest fire site of the power transmission line is high, and the evaporation capacity of the fire extinguishing water agent in the falling process reaches 60% -80%, so that the evaporation capacity of the fire extinguishing water agent must be considered when the aviation fire extinguishing evaluation of the forest fire of the power transmission line is carried out. In addition, the vegetation on the site is dense, when the fire extinguishing water agent is sprayed to the combustible on the top, the fire extinguishing water agent can not reach the ground surface combustible, and the factors such as the flow characteristic and the vegetation density of the fire extinguishing water agent after reaching the fire scene are also key factors influencing the fire extinguishing effect of the forest fire of the power transmission line. Therefore, in most cases, the fire extinguishing experience of pilots is greatly different from that of fire extinguishing sites, so that the fire extinguishing flow has to be increased for achieving the purpose of fire extinguishing, the fire extinguishing flow is extremely large, a large amount of fire extinguishing water agent is wasted, and the waste of a large amount of manpower and material resources is caused 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 guidance basis needs to be provided. Therefore, an aviation accurate fire extinguishing calculation method is urgently needed.
At the present stage, no aviation fire extinguishing guidance method exists.
Disclosure of Invention
The invention aims to provide an aviation accurate fire extinguishing assessment method and an assessment system thereof, so as to solve the technical defects in the prior art.
In order to achieve the purpose, the invention provides an aviation accurate fire extinguishing assessment method, which comprises the following steps:
acquiring internal parameters of the aviation fire extinguishing device and external parameters of a fire scene;
calculating the falling dosage of the fire extinguishing water agent in the unit area of the fire scene by integrating the internal parameters and the external parameters;
evaluating the fire extinguishing effect according to the falling 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 flight 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 field wind speed, the fire field wind direction, the fire field temperature and the vegetation type.
Preferably, the step of calculating the landing dosage of the fire extinguishing water agent in the unit area of the fire scene by integrating 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 contact area of the fire extinguishing agent, the dispersion state of the fire extinguishing agent and the latent heat of evaporation of the fire extinguishing agent; calculating the total drift amount of the fire extinguishing agent which does not fall into the forest fire area in the falling process according to the speed and the acceleration of the fire extinguishing agent at different heights and different times; calculating the shielded amount of the fire extinguishing water agent according to the vegetation type of the fire scene, the flow rate of the fire extinguishing water agent and the total evaporation amount;
and calculating the falling dosage of the fire extinguishing agent in the unit area of the fire scene according to the flow of the fire extinguishing agent, the total evaporation amount of the fire extinguishing agent, the total drift amount of the fire extinguishing agent and the shielded amount of the fire extinguishing agent.
Preferably, the calculation method of the speed and the acceleration of the fire extinguishing water agent at different heights and different times comprises the following steps:
decomposing the ejection speed of the fire extinguishing agent into a horizontal speed vx0And a vertical velocity vy0(ii) a Decomposition of fire field wind speed into horizontal wind speed vw1And vertical plume velocity vw2；
Divide into two-layer with the water agent of putting out a fire, be projection cone angle layer and projection rectangle layer respectively, wherein, the acceleration and the speed that the horizontal wind speed of projection cone angle layer acted on the water agent of putting out a fire are:
Figure BDA0002405772680000021
vx1＝vx0-∫αx1dt
in the formula, L1Radius of the bottom round surface of the cone angle layer, v1xFor horizontal velocity of water agent for fire extinguishing, rhoaIs the air density, pjThe density of the fire extinguishing water agent;
the acceleration and the speed of the projection rectangular layer horizontal wind speed acting on the fire extinguishing water agent are as follows:
Figure BDA0002405772680000022
vx2＝vx1-∫αx2dt
in the formula, L2The side length of a square at the bottom of the projection rectangular layer is shown;
the acceleration and the speed of the projection cone angle layer in the vertical direction wind resistance and the gravity acting on the water body are as follows:
wherein the wind resistance in the vertical direction of the projection cone angle layer is as follows:
Figure BDA0002405772680000023
wherein H is the vertical height of the projection cone angle layer, v1yVertical velocity of water agent for fire extinguishing, g is gravitational acceleration, CdIs the coefficient of air resistance, wherein the coefficient of air resistance CdRelated to the reynolds number of the fluid:
Figure BDA0002405772680000031
Figure BDA0002405772680000032
l is the characteristic length associated with the cross-sectional area of the object, ρ is the fluid density, η is the viscosity of the fluid, then:
Figure BDA0002405772680000033
thereby calculating the acceleration and the speed of the wind resistance and the gravity acting on the water body in the vertical direction of the projection cone angle layer;
the acceleration and the speed of the wind resistance and the gravity acting on the water body in the vertical direction of the rectangular projection layer are as follows:
wherein the wind resistance in the vertical direction of the rectangular projection layer is as follows:
Figure BDA0002405772680000034
then:
Figure BDA0002405772680000035
thereby calculating and obtaining the acceleration and the speed of the wind resistance and the gravity of the projection rectangular layer in the vertical direction acting on the water body.
Preferably, the total evaporation amount of the fire extinguishing water agent in the falling process is calculated according to an evaporation model, wherein the evaporation model is as follows:
under the water height of the fire extinguishing water agent, namely x is more than 0 and less than H, Y2＜y＜L：
Figure BDA0002405772680000036
In the water body of the fire extinguishing water agent, namely x is more than 0 and less than H, Y1＜y＜Y2：
Figure BDA0002405772680000037
Above the water body height of the fire extinguishing water agent, namely x is more than 0 and less than H, Y is more than 0 and less than Y1：
Figure BDA0002405772680000038
In the formula, Y1＝Vd·t，Y2＝Ld+VdT, where t is time, VdThe life cycle of the fire extinguishing agent is shown, T is the temperature of a fire scene, gamma is the heat conduction coefficient of the fire extinguishing agent, gamma is lambda/Crho, lambda is the heat conduction coefficient of the fire extinguishing agent, and C is the specific heat capacity of the fire extinguishing agent.
Preferably, the step of calculating the shielded quantity of the fire extinguishing water agent according to the vegetation type of the fire scene, the flow rate of the fire extinguishing water agent and the total evaporation quantity comprises the following steps:
acquiring vegetation types including a shading coefficient and vegetation space density corresponding to the vegetation types;
calculating the shielding amount according to the shielding coefficient, the vegetation space density, the total evaporation amount and the proportion of the fire extinguishing water agent:
Figure BDA0002405772680000041
wherein β is the shading coefficient, Q0Is the flow of the fire extinguishing water agent, p is the proportion of the fire extinguishing water agent, QvapFor total amount of evaporation, pveIs the spatial density of vegetation.
Preferably, before the floor-falling dose of the fire-extinguishing water agent is calculated, the horizontal displacement of the fire-extinguishing water agent needs to be determined, and the calculation mode of the horizontal displacement of the fire-extinguishing water agent is as follows:
the whole area is a rectangular area consisting of the length D of the water belt and the diameter 2b of the circular area;
the length D of the water belt is the straight running distance D of the aviation fire extinguishing device in the whole water supply processaAnd the sum of the diffusion radius b of the water body on the helicopter course at the moment of starting and finishing water throwing, namely:
D＝Da+2b
wherein the aviation extinguishing device is thrown the water course and is gone straight line distance DaComprises the following steps:
Da＝[V0+Ucos(-ΔK)]T0
in the formula, V0The flying speed of the aviation fire extinguishing device is U, the wind speed and the wind direction are U, delta K is a course correction value, and T is0Time taken for fire-extinguishing helicopter to throw water, wherein, T0＝M*/nπd2u0And n is the number of the nozzles.
Preferably, the drop dose of the fire extinguishing water agent is:
Figure BDA0002405772680000042
in the formula, M*The water feeding amount is S is the water feeding area, wherein,
Figure BDA0002405772680000043
Figure BDA0002405772680000044
preferably, the Reynolds number Re > 30.
Based on the method, the invention also discloses an aviation accurate fire-extinguishing assessment system which comprises a processor, a memory and a computer program stored in the memory, wherein the processor executes the computer program to realize any one of the methods.
The invention has the following beneficial effects:
the method considers the sum of the flight speed of the aviation fire extinguishing device and the acceleration vector of the fire extinguishing agent under the action of the wind of the site environment and the smoke plume of the fire scene, and accurately calculates the horizontal displacement of the fire extinguishing agent; the contact area and the evaporation capacity of the fire extinguishing agent at different fire field temperatures are calculated, so that the fire extinguishing agent dosage of the power transmission line forest fire unit area is accurately obtained, and an evaluation basis is provided for fire extinguishing of the aviation helicopter.
The present invention will be described in further detail below with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic diagram of fire suppression of an aviation fire suppression unit according to a preferred embodiment of the present invention;
FIG. 2 is a schematic diagram illustrating the position scale of the fire-extinguishing water agent in the falling process according to the preferred embodiment of the invention;
fig. 3 is a fire extinguishing method and a fire extinguishing system thereof for aviation according to the preferred embodiment of the invention.
Detailed Description
The embodiments of the invention will be described in detail below with reference to the drawings, but the invention can be implemented in many different ways as defined and covered by the claims.
The invention firstly provides an aviation accurate fire extinguishing assessment method, which comprises the following steps of:
s1: and 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 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 field wind speed, the fire field wind direction, the fire field temperature and the vegetation type.
See the figureIn this embodiment, it is assumed that the fire extinguishing agent is uniformly sprayed from the water outlet at a certain initial speed. When the Reynolds number Re is more than 3, the jet flow is turbulent, and the Reynolds number value range is 0-Re-105. Therefore, the reynolds number Re is set to be larger than 30 in the present embodiment. The ejection speed of the fire extinguishing agent can be decomposed into a horizontal speed vx0And a vertical velocity vy0(ii) a The wind speed of the fire scene can be decomposed into a horizontal wind speed vw1And vertical plume velocity vw2(ii) a The fire scene temperature 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 field temperatures include the fire field temperature at each height of the fire field. Furthermore, the flight pitch angle of the aerial fire-extinguishing device can also be directly obtained from the aerial fire-extinguishing device or a remote system communicating with the aerial fire-extinguishing device.
S2: and calculating the falling dosage of the fire extinguishing water agent in the unit area of the fire scene by integrating the internal parameters and the external parameters.
The landing dosage of the fire extinguishing water agent is a key factor for evaluating the fire extinguishing effect, so that the landing dosage of the fire extinguishing water agent in a unit area of a fire scene needs to be calculated. The method comprises the following steps:
s21: and calculating the speed and the 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 the fire scene.
The stress of the fire extinguishing water aqua is calculated according to the wind speed of the site environment, and the acceleration and the speed of the water body in the horizontal direction and the vertical direction at different heights and different time points are obtained.
Divide into two-layer with the water agent of putting out a fire, be projection cone angle layer and projection rectangle layer respectively, wherein, the acceleration and the speed that the horizontal wind speed of projection cone angle layer acted on the water agent of putting out a fire are:
Figure BDA0002405772680000051
vx1＝vx0-∫αx1dt
wherein C is air resistance coefficient, and its value is 0.5-1.0, L1Radius of the bottom round surface of the cone angle layer, vx1For extinguishing water agent in the projection cone angle layerEnd horizontal velocity of paIs the air density, pjThe density of the fire extinguishing water agent;
the acceleration and the speed of the projection rectangular layer horizontal wind speed acting on the fire extinguishing water agent are as follows:
Figure BDA0002405772680000061
vx2＝vx1-∫αx2dt
in the formula, L2For projecting the side length, v, of a square at the bottom of a rectangular layerx2The horizontal speed of the fire extinguishing agent at the tail end of the projection rectangular layer is adopted;
the acceleration and the speed of the projection cone angle layer in the vertical direction wind resistance and the gravity acting on the water body are as follows:
wherein the wind resistance in the vertical direction of the projection cone angle layer is as follows:
Figure BDA0002405772680000062
wherein H is the vertical height of the projection cone angle layer, v1yVertical velocity of fire extinguishing agent at the end of the projection rectangular layer, g is gravity acceleration, CdIs the coefficient of air resistance, wherein the coefficient of air resistance CdRelated to the reynolds number of the fluid:
Figure BDA0002405772680000063
Figure BDA0002405772680000064
l is the characteristic length associated with the cross-sectional area of the object, ρ is the fluid density, η is the viscosity of the fluid, then:
Figure BDA0002405772680000065
thereby calculating the acceleration and the speed of the wind resistance and the gravity acting on the water body in the vertical direction of the projection cone angle layer;
the acceleration and the speed of the wind resistance and the gravity acting on the water body in the vertical direction of the rectangular projection layer are as follows:
wherein the wind resistance in the vertical direction of the rectangular projection layer is as follows:
Figure BDA0002405772680000066
then:
Figure BDA0002405772680000067
thereby calculating the acceleration and the speed v of the projection rectangular layer in the vertical direction of the wind resistance and the gravity acting on the fire extinguishing agent2yThe vertical speed of the fire extinguishing agent at the tail end of the projection rectangular layer.
The acceleration and the speed of the fire extinguishing water agent acting on the projection cone angle layer by the natural wind of the projection cone angle layer are the acceleration and the speed of the fire extinguishing water agent per se; in the same way, the acceleration and the speed of the fire extinguishing water agent acted by the natural wind of the projection rectangular layer are the acceleration and the speed of the fire extinguishing water agent of the projection rectangular layer.
The falling time of the fire extinguishing water agent can be calculated according to the acceleration and the speed of the fire extinguishing water agent.
When the falling time is calculated, the coverage area is simplified into a circular area which takes the center falling point as the center of a circle and the average distance between the center falling point and the boundary as the radius.
S22: 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 contact area of the fire extinguishing agent, the dispersion state of the fire extinguishing agent and the latent heat of evaporation of the fire extinguishing agent; calculating the total drift amount of the fire extinguishing agent which does not fall into the forest fire area in the falling process according to the speed and the acceleration of the fire extinguishing agent at different heights and different times; and calculating the shielded amount of the fire extinguishing water agent according to the vegetation type of the fire scene, the flow rate of the fire extinguishing water agent and the total evaporation amount.
The dispersion state of the fire extinguishing agent is defined as the cone angle theta of the projection cone angle layer; the contact area of the fire extinguishing water agent is that the fire extinguishing water agent is put into useShadow cone angle layer surface area
Figure BDA0002405772680000071
And surface area of projected rectangular layer 4L2H2In which H is1For projection of cone angle layer cone height, H2The height of the rectangular body of the rectangular projection layer is set; the latent heat of evaporation of the fire extinguishing water agent is the inherent property of the fire extinguishing water agent, and when the formula and the proportion of the fire extinguishing water agent are determined, the latent heat of evaporation is also determined, and the latent heat of evaporation can be determined by adopting a common physical method before the fire extinguishing water agent is added.
S221: and 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 contact area of the fire extinguishing agent, the dispersion state of the fire extinguishing agent and the latent heat of evaporation of the fire extinguishing agent.
The method for calculating the evaporation capacity of the fire extinguishing agent in the falling process comprises the following steps:
according to the temperature distribution T of the fire field at different heightsyCalculating the evaporation capacity of the fire extinguishing agent at different heights by using the contact area of the fire extinguishing agent, the dispersion state of the fire extinguishing agent and the latent heat of evaporation of the fire extinguishing agent, and calculating the total evaporation quantity Q of the fire extinguishing agent in the falling process by adopting an integral methodvap. And the total evaporation 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 in the falling process, the 1 st stage is an integral water column stage, and the 2 nd stage is a scattering water body stage, wherein the scattering water body in the 2 nd stage is divided into 10 grades according to the diameter of water drops.
The evaporation model is then:
below the height of the fire extinguishing agent, namely x is more than 0 and less than H, Y2＜y＜L：
Figure BDA0002405772680000072
In the fire extinguishing water agent, i.e. x is more than 0 and less than H, Y1＜y＜Y2：
Figure BDA0002405772680000073
Above the height of the fire extinguishing agent, namely x is more than 0 and less than H, Y is more than 0 and less than Y1：
Figure BDA0002405772680000074
In the formula, Y1＝Vd·t，Y2＝Ld+VdT, where t is time, VdThe life cycle of the fire extinguishing agent is shown, T is the temperature of a fire scene, gamma is the heat conduction coefficient of the fire extinguishing agent, gamma is lambda/Crho, lambda is the heat conduction coefficient of the fire extinguishing agent, and C is the specific heat capacity of the fire extinguishing agent.
The invention considers that evaporation can be only carried out on the surface of the water body, so that the evaporation surfaces are a conical surface in the integral water column stage and three rectangular surfaces in the scattering water body stage.
Boundary conditions:
in the water column stage:
Figure BDA0002405772680000081
Figure BDA0002405772680000082
Qjw is the evaporation heat absorption (J/kg) of the fire extinguishing water agentjThe evaporation rate of the fire extinguishing water agent. VdThe falling speed of the fire extinguishing water agent is adopted.
S222: and calculating the total drift amount of the fire extinguishing agent which does not fall into the forest fire area in the falling process according to the speed and the acceleration of the fire extinguishing agent at different heights and different times.
According to the acceleration integral and the speed of the fire extinguishing agent in the horizontal direction, the horizontal displacement of the fire extinguishing agent is obtained by an integral method, the area where the fire extinguishing agent reaches the ground is drawn, and the fire extinguishing agent dose which does not fall into the area where the forest fire burns is the drift amount Qsh。
When calculating the horizontal displacement, the whole area is a rectangular area consisting of the length D of the water band and the diameter 2b of the circular area;
the length D of the water belt is the straight running distance D of the aviation fire extinguishing device in the whole water supply processaAnd the sum of the diffusion radius b of the fire extinguishing water agent on the helicopter course at the moment of starting and finishing water feeding, namely:
D＝Da+2b
wherein the aviation extinguishing device is thrown the water course and is gone straight line distance DaComprises the following steps:
Da＝[V0+Ucos(-ΔK)]T0
in the formula, V0The flying speed of the aviation fire extinguishing device is U, the wind speed and the wind direction are U, delta K is a course correction value, and T is0Time taken for fire-extinguishing helicopter to throw water, wherein, T0＝M*/nπd2u0，
Figure BDA0002405772680000083
Namely the initial spraying speed of the fire extinguishing agent is the square sum of the horizontal initial speed and the vertical initial speed, and n is the number of the nozzles.
S223: calculating the shielding amount of the fire extinguishing water agent according to the vegetation type of the fire scene, the flow rate of the fire extinguishing water agent and the total evaporation amount
Calculating the shielding amount of the fire extinguishing water agent according to the forest fire vegetation type, the vegetation transmission coefficient, the forest fire type, the viscosity and the concentration of the fire extinguishing water agent of the power transmission line
S2231: and acquiring the vegetation type, wherein the vegetation type comprises a shading coefficient corresponding to the vegetation type and vegetation space density.
Due to the fact that the variety of vegetation combustibles on the electric transmission line forest fire site is large, classification calculation needs to be conducted according to the vegetation type, the forest fire type and the fire extinguishing agent parameter, and the following table 1 is a fire scene shading coefficient β distribution table.
TABLE 1 fire scene shading coefficient β of aviation fire extinguishing device
Figure BDA0002405772680000091
S2232: and calculating the shielded amount according to the shielding coefficient, the vegetation space density, the total evaporation amount and the proportion of the fire extinguishing water agent.
The proportion of the fire extinguishing water agent is p, and the concentration of the fire extinguishing water agent when the fire extinguishing water agent reaches vegetation combustible substances is obtained according to the total evaporation amount
Figure BDA0002405772680000092
With the increase of the concentration of the fire extinguishing agent, 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. Through experiments, the concentration and the viscosity of the fire extinguishing agent are in direct proportion, and therefore, the concentration of the fire extinguishing agent in the fire extinguishing water agent is directly used as a key parameter for calculating the shielding amount.
Although the fire extinguishing water agent has fluidity, when the shielding density of vegetation combustible substances is high, the blocking effect on the fire extinguishing water agent is increased, so that the fire extinguishing water agent cannot reach a combustion area of a fire scene at the same time, and the fire extinguishing effect is reduced. Thus, the present invention uses the in situ combustible space density ρveAs an influence factor that influences the shielding amount of the water agent for fire extinguishing.
Figure BDA0002405772680000093
Wherein β is the shading coefficient, Q0Is the flow of the fire extinguishing water agent, p is the proportion of the fire extinguishing water agent, QvapFor total amount of evaporation, pveη is a correction coefficient, which takes the value of
Figure BDA0002405772680000094
S23: and calculating the falling dosage of the fire extinguishing agent in the unit area of the fire scene according to the flow of the fire extinguishing agent, the total evaporation amount of the fire extinguishing agent, the total drift amount of the fire extinguishing agent and the shielded amount of the fire extinguishing agent.
Flow Q according to an aerial fire extinguishing device0Drift amount QshAnd evaporation capacity QvapCalculating the effective fire extinguishing dose Q of the fire extinguishing agent reaching the groundex。
S3: and evaluating the fire extinguishing effect according to the falling dosage of the fire extinguishing agent in the unit area of the fire scene.
Intersection area S of area where fire extinguishing agent reaches ground and actual forest fire burning area of power transmission linefIn an effective extinguishing dose QexDivided by the cross-over area SfAnd obtaining the amount of the scattered fire field in unit area.
The falling dosage of the fire extinguishing water agent is as follows:
Figure BDA0002405772680000101
in the formula, M*The water feeding amount is S is the water feeding area, wherein,
Figure BDA0002405772680000102
Figure BDA0002405772680000103
s4: and adjusting internal parameters according to the fire extinguishing effect until the fire extinguishing effect is maximized.
By means of the method, the invention further discloses an aviation accurate fire extinguishing assessment system which comprises a processor, a memory and a computer program stored in the memory, wherein any one of the methods is realized when the processor executes the computer program.
According to the method, the time of the fire extinguishing water agent falling to the ground is calculated by establishing a stress analysis model of the aviation fire extinguishing device, so that the displacement of the fire extinguishing water agent in the horizontal direction is further obtained; calculating the evaporation capacity of the fire extinguishing water agent in the falling process by combining the interaction of the fire extinguishing water agent and high-temperature air; and calculating the shielding amount of the aerial fire-extinguishing water agent reaching the fire scene according to the parameters of the forest fire type, the vegetation density, the concentration of the fire-extinguishing agent and the like of the power transmission line forest fire scene. On the basis, the area and unit area dosage of the fire extinguishing water agent falling to the fire scene are calculated, and the forest fire extinguishing accuracy and effect of the power transmission line are improved.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. An aviation accurate fire extinguishing assessment method is characterized by comprising the following steps:
acquiring internal parameters of the aviation fire extinguishing device and external parameters of a fire scene;
calculating the falling dosage of the fire extinguishing water agent in the unit area of the fire scene by integrating the internal parameters and the external parameters;
and evaluating the fire extinguishing effect according to the falling dosage of the fire extinguishing agent in the unit area of the fire scene.
2. The aviation accurate fire extinguishing assessment method according to claim 1, wherein 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 field wind speed, the fire field wind direction, the fire field temperature and the vegetation type.
3. The aviation precise fire extinguishing assessment method according to claim 2, wherein the step of calculating the landing dose of the fire extinguishing water agent in the unit area of the fire scene by integrating 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 latent heat of evaporation of the fire extinguishing agent; calculating the total drift amount of the fire extinguishing agent which does not fall into the forest fire area in the falling process according to the speed and the acceleration of the fire extinguishing agent at different heights and different times; calculating the utilization amount of the fire extinguishing water agent according to the vegetation type of the fire scene, the flow of the fire extinguishing water agent and the total evaporation amount;
and calculating the falling dosage of the fire extinguishing agent in the unit area of the fire scene according to the flow of the fire extinguishing agent, the total evaporation amount of the fire extinguishing agent, the total drift amount of the fire extinguishing agent and the utilization amount of the fire extinguishing agent.
4. The aviation accurate fire extinguishing assessment method according to claim 3, wherein the calculation method of the speed and acceleration of the fire extinguishing water agent at different heights and different times comprises the following steps:
decomposing the ejection speed of the fire extinguishing agent into a horizontal speed vx0And a vertical velocity vy0(ii) a Decomposition of fire field wind speed into horizontal wind speed vw1And vertical plume velocity vw2；
Divide into two-layer with the water agent of putting out a fire, be projection cone angle layer and projection rectangle layer respectively, wherein, the acceleration and the speed that the horizontal wind speed of projection cone angle layer acted on the water agent of putting out a fire are:
Figure FDA0002405772670000011
vx1＝vx0-∫αx1dt
wherein C is air resistance coefficient, and its value is 0.5-1.0, L1Radius of the bottom round surface of the cone angle layer, vx1Horizontal velocity rho of fire extinguishing agent at the end of projection cone angle layeraIs the air density, pjThe density of the fire extinguishing water agent;
the acceleration and the speed of the projection rectangular layer horizontal wind speed acting on the fire extinguishing water agent are as follows:
Figure FDA0002405772670000021
vx2＝vx1-∫αx2dt
in the formula, L2For projecting the side length, v, of a square at the bottom of a rectangular layerx2The horizontal speed of the fire extinguishing agent at the tail end of the projection rectangular layer is adopted;
the acceleration and the speed of the projection cone angle layer in the vertical direction wind resistance and the gravity acting on the water body are as follows:
wherein the wind resistance in the vertical direction of the projection cone angle layer is as follows:
Figure FDA0002405772670000022
wherein H is the vertical height of the projection cone angle layer, v1yVertical velocity of fire extinguishing agent at the end of projection cone angle layer, g is gravity acceleration, CdIs the coefficient of air resistance, wherein the coefficient of air resistance CdRelated to the reynolds number of the fluid:
Figure FDA0002405772670000023
Figure FDA0002405772670000024
l is the characteristic length associated with the cross-sectional area of the object, ρ is the fluid density, η is the viscosity of the fluid, then:
Figure FDA0002405772670000025
thereby calculating the acceleration and the speed of the wind resistance and the gravity acting on the water body in the vertical direction of the projection cone angle layer;
the acceleration and the speed of the wind resistance and the gravity acting on the water body in the vertical direction of the rectangular projection layer are as follows:
wherein the wind resistance in the vertical direction of the rectangular projection layer is as follows:
Figure FDA0002405772670000026
then:
Figure FDA0002405772670000027
thereby calculating the wind resistance of the projection rectangular layer in the vertical direction,Acceleration and velocity of gravity acting on a body of water, v2yThe vertical speed of the fire extinguishing agent at the tail end of the projection rectangular layer.
5. The aviation precise fire extinguishing assessment method according to claim 3, wherein 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:
under the water height of the fire extinguishing water agent, namely x is more than 0 and less than H, Y2＜y＜L：
Figure FDA0002405772670000028
In the water body of the fire extinguishing water agent, namely x is more than 0 and less than H, Y1＜y＜Y2：
Figure FDA0002405772670000031
Above the water body height of the fire extinguishing water agent, namely x is more than 0 and less than H, Y is more than 0 and less than Y1：
Figure FDA0002405772670000032
In the formula, Y1＝Vd·t，Y2＝Ld+VdT, where t is time, VdThe life cycle of the fire extinguishing agent is shown, T is the temperature of a fire scene, gamma is the heat conduction coefficient of the fire extinguishing agent, gamma is lambda/Crho, lambda is the heat conduction coefficient of the fire extinguishing agent, and C is the specific heat capacity of the fire extinguishing agent.
6. The aviation accurate fire extinguishing assessment method according to claim 3, wherein the step of calculating the utilization amount of the fire extinguishing water agent according to the type of vegetation in the fire scene, the flow rate of the fire extinguishing water agent and the total evaporation amount comprises the following steps:
acquiring vegetation types including a shading coefficient and vegetation space density corresponding to the vegetation types;
calculating the utilization amount of the fire extinguishing water agent according to the shielding coefficient, the vegetation space density, the total evaporation amount and the proportion of the fire extinguishing water agent:
Figure FDA0002405772670000033
wherein β is the shading coefficient, Q0Is the flow of the fire extinguishing water agent, p is the proportion of the fire extinguishing water agent, QvapFor total amount of evaporation, pveIs the spatial density of vegetation, w is the correction coefficient, and the value is
Figure FDA0002405772670000034
7. The aviation accurate fire extinguishing assessment method according to claim 3, wherein the horizontal displacement of the fire extinguishing water agent is further determined before the ground falling dose of the fire extinguishing water agent is calculated in a manner that:
the whole area is a rectangular area consisting of the length D of the water belt and the diameter 2b of the circular area;
the length D of the water belt is the straight running distance D of the aviation fire extinguishing device in the whole water supply processaAnd the sum of the diffusion radius b of the water body on the helicopter course at the moment of starting and finishing water throwing, namely:
D＝Da+2b
wherein the aviation extinguishing device is thrown the water course and is gone straight line distance DaComprises the following steps:
Da＝[V0+Ucos(-ΔK)]T0
in the formula, V0The flying speed of the aviation fire extinguishing device is U, the wind speed and the wind direction are U, delta K is a course correction value, and T is0Time taken for fire-extinguishing helicopter to throw water, wherein, T0＝4M*/nπd2u0，
Figure FDA0002405772670000035
Namely the initial speed of the fire extinguishing agent is the square sum of the horizontal initial speed and the vertical initial speed, and n is the nozzleThe number of (2).
8. The aviation precise fire extinguishing assessment method according to claim 7, wherein the falling dosage of the fire extinguishing water agent is as follows:
Figure FDA0002405772670000041
in the formula, M*The water feeding amount is S is the water feeding area, wherein,
Figure FDA0002405772670000042
Figure FDA0002405772670000043
9. the aviation precise fire extinguishing assessment method according to claim 3, wherein the Reynolds number Re > 30.
10. An airborne fire-fighting assessment system comprising a processor, a memory and a computer program stored on the memory, wherein the processor, when executing the computer program, implements the method of any of claims 1-9.
CN202010160985.XA 2020-03-10 2020-03-10 Aviation accurate fire extinguishing evaluation method and evaluation system thereof Active CN111401715B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010160985.XA CN111401715B (en) 2020-03-10 2020-03-10 Aviation accurate fire extinguishing evaluation method and evaluation system thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010160985.XA CN111401715B (en) 2020-03-10 2020-03-10 Aviation accurate fire extinguishing evaluation method and evaluation system thereof

Publications (2)

Publication Number Publication Date
CN111401715A true CN111401715A (en) 2020-07-10
CN111401715B CN111401715B (en) 2023-10-10

Family

ID=71428694

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010160985.XA Active CN111401715B (en) 2020-03-10 2020-03-10 Aviation accurate fire extinguishing evaluation method and evaluation system thereof

Country Status (1)

Country Link
CN (1) CN111401715B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111882811A (en) * 2020-07-27 2020-11-03 安徽九洲农业科技有限公司 Fire-fighting unmanned aerial vehicle for identifying fire point
CN115826619A (en) * 2022-11-30 2023-03-21 航宇救生装备有限公司 Accurate fire extinguishing auxiliary device of helicopter fire-fighting bucket
CN116007643A (en) * 2022-11-30 2023-04-25 航宇救生装备有限公司 Intelligent auxiliary method for accurate fire extinguishment of helicopter fire-fighting bucket

Citations (6)

* Cited by examiner, † Cited by third party
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
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
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

Patent Citations (6)

* Cited by examiner, † Cited by third party
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
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
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 (4)

* Cited by examiner, † Cited by third party
Title
OLGA V. VYSOKOMORNAYA ET AL.: "Experimental investigation of atomized water droplet initial parameters influence on evaporation intensity in flaming combustion zone" *
周特军: "输电线路山火无人机监测与灭火技术研究" *
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" *
王永亮: "大型灭火飞机投水算法" *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111882811A (en) * 2020-07-27 2020-11-03 安徽九洲农业科技有限公司 Fire-fighting unmanned aerial vehicle for identifying fire point
CN115826619A (en) * 2022-11-30 2023-03-21 航宇救生装备有限公司 Accurate fire extinguishing auxiliary device of helicopter fire-fighting bucket
CN116007643A (en) * 2022-11-30 2023-04-25 航宇救生装备有限公司 Intelligent auxiliary method for accurate fire extinguishment of helicopter fire-fighting bucket

Also Published As

Publication number Publication date
CN111401715B (en) 2023-10-10

Similar Documents

Publication Publication Date Title
CN111401715A (en) Aviation accurate fire extinguishing assessment method and assessment system thereof
Zhou et al. Effects of droplet formation patterns on the atomization characteristics of a dust removal spray in a coal cutter
KR101955780B1 (en) Automatic high-speed rotary atomizing device, use thereof and a fire extinguishing method by using same
CN113325735B (en) Particle swarm algorithm-based rapid water-feeding fire-extinguishing strategy planning method
US11666788B2 (en) Wide-area fire-retardant system using distributed dense water fogger
Wadhwani et al. A review of firebrand studies on generation and transport
CN111388908B (en) Aviation fire extinguishing parameter obtaining method and system
Yang et al. Numerical study on water curtain system for fire evacuation in a long and narrow tunnel under construction
CN109045541B (en) Control method and system for unmanned aerial vehicle fire extinguishing device for overcoming fire field smoke plume and storage medium
dos Santos et al. Effects of urban boundary layer turbulence on firebrand transport
Wadhwani et al. Simulated transport of short-range embers in an idealised bushfire
Yen et al. Evaluation of wetting measures and capture efficiencies of fugitive dust emitted from a limestone pile: Experiments and artificial neural network
Fesal et al. A numerical analysis of flat fan aerial crop spray
CN104863631B (en) The optimization method that reduction uranium ore gaseous effluent is endangered surrounding enviroment
CN107349540A (en) A kind of unmanned plane extinguishing method based on the division of fire of high-rise building spatial domain
Cramer A brief survey of the meteorological aspects of atmospheric pollution
Teske et al. A simulation of boom length effects for drift minimization
Santos et al. Effects of Urban Boundary Layer Turbulence on Firebrand Transport
Hall et al. Deposition of large particles from warehouse fire plumes—a small-scale wind tunnel model study
CN118410307A (en) Fire extinguishing treatment method and device for mountain fire area of irregularly-shaped power transmission line
CN111317941B (en) Cooperative control method and system for insulation and evaporation prevention performance based on aviation fire extinguishing
Chen Establishment and Simulation Analysis of Aviation Sprinkler Model
Satoh et al. Experiments and Numerical Simulations of Flow Patterns of Water Droplets From Fire-Fighting Helicopters
Ellis et al. Human exposure to spray drift: investigations into modelling the spray exposure of residents and bystanders and its variability.
Genii et al. Disintegration of Free-falling Liquid Droplets, Jets, and Arrays in Air

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant