A method for calculating the intensity of water jet drop from fire monitors based on multivariate linear regression

Abstract

The invention discloses a method for calculating the falling point strength of a water jet of a fire cannon based on multiple linear regression, and relates to the field of water jets of fire cannons. The method uses the structural parameters of the fire cannon to calculate the cross-sectional parameters, obtains the working pressure of the fire cannon, determines the calculation formula of the initial velocity of the water jet at the muzzle of the fire cannon according to the Bernoulli equation, calculates the initial velocity of the water jet at the muzzle of the fire cannon according to the structural parameters of the fire cannon, uses the relationship between the flow rate and the flow velocity, and combines the working pressure of the fire cannon to calculate the actual falling point strength of the water jet of the fire cannon according to the flow rate and the actual falling point area of ​​the water jet of the fire cannon, and establishes a calculation formula for the falling point strength of the water jet of the fire cannon based on the multiple linear regression method by dimensionlessly converting the inclination angle, working pressure, initial velocity of the water jet at the muzzle and the actual falling point strength of the fire cannon, and verifies its accuracy; the invention realizes the quantitative calculation of the falling point strength of the water jet of the fire cannon, and lays a foundation for the accurate layout of fire fighting tactics.

Description

Technical Field

[0001] The invention belongs to the field of fire-fighting water monitors, and in particular relates to a method for calculating the intensity of water jets falling points of fire-fighting monitors based on multiple linear regression. Background Art

[0002] As one of the most widely used fire-fighting equipment in actual firefighting, fire monitors can implement long-distance firefighting and cooling protection in safe areas outside the fire scene heat radiation, explosion hazards, and toxic smoke areas. They have the characteristics of high firefighting efficiency and great power, and have become essential equipment in mobile firefighting equipment such as fire trucks and fire boats. Petrochemical fires are characterized by violent combustion, high radiant heat, and difficulty for firefighters to approach. Therefore, fire monitors can be seen everywhere in key dangerous places in the petrochemical industry. Fire monitors play an irreplaceable role in regional fire fighting in petrochemicals, airports, docks, etc. In my country's current oil terminal design specifications, hangar design specifications, and low-multiple foam design specifications, it is clearly stipulated that fire monitors are the main means of fire protection.

[0003] With the rapid development of my country's national economy, the application of fire monitors will be more extensive, and their advantages will become more prominent. As an important factor in determining the efficiency of fire monitor water jet fire extinguishing, especially in special and complex fire scenes, the prediction of the water jet landing point strength of fire monitors is the key to fire extinguishing. Therefore, research on the jet landing point strength of fire monitors will help deepen the understanding of fire monitor performance and improve the application level of fire monitors.

[0004] However, there are few literatures on the quantitative calculation of the intensity of the water jet landing point of fire cannons, and most of them focus on the study of the water jet trajectory. For example, Wan Feng et al. proposed to derive the fire cannon water jet trajectory equation based on the experimental trajectory according to the particle kinematics theory. The jet trajectory calculated by this method is basically consistent with the experimental trajectory, which laid a theoretical foundation for the subsequent study of jet trajectories; Yao Bin, Shu Ya et al. conducted a qualitative study on the distribution characteristics and laws of the water spray intensity of fire cannon water jets through experiments, but none of the existing studies involved the quantitative calculation of the intensity of the water jet landing point of fire cannons.

[0005] Therefore, it is urgent to propose a method for calculating the strength of the water jet landing point of a fire monitor and quantitatively calculate the strength of the water jet landing point of a fire monitor. Summary of the invention

[0006] In order to achieve quantitative calculation of the intensity of water jets falling from fire monitors and provide a more accurate reference for fire fighting tactical layout, the present invention proposes a method for calculating the intensity of water jets falling from fire monitors based on multivariate linear regression.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] A method for calculating the intensity of water jet drop points of fire monitors based on multiple linear regression specifically comprises the following steps:

[0009] Step 1: Dimensionless processing of various parameters of fire monitors, specifically including the following steps:

[0010] Step 1.1, calculate the cross-sectional parameters of the fire monitor according to the structural parameters of the fire monitor;

[0011] Step 1.2, obtaining the gun seat pressure of the fire monitor and determining the working pressure of the fire monitor;

[0012] Step 1.3, based on the Bernoulli equation, determine the calculation formula for the initial velocity of the water jet at the muzzle of the fire monitor;

[0013] Step 1.4, according to the structural parameters of the fire monitor, using the relationship between the flow rate and the flow velocity in the fire monitor, respectively determine the speed of the water jet at the bottom and the muzzle of the fire monitor, and calculate the initial speed of the water jet at the muzzle of the fire monitor in combination with the working pressure of the fire monitor;

[0014] Step 1.5, calculating the actual landing point intensity of the fire monitor water jet according to the flow rate and actual landing point area of ​​the fire monitor water jet;

[0015] Step 1.6, respectively non-dimensionalize the inclination angle, working pressure, initial velocity of the water jet at the muzzle, and actual landing point intensity of the water jet of the fire monitor;

[0016] Step 2, by analyzing the dimensionless fire monitor inclination angle, working pressure, actual water jet landing intensity and initial water jet velocity at the muzzle, determine the relationship between the parameters of the fire monitor, establish a multiple linear regression equation of the fire monitor water jet landing intensity based on the multiple linear regression method, and calculate the predicted value of the fire monitor water jet landing intensity;

[0017] Step 3, based on the predicted value of the fire monitor water jet landing intensity and the measured value of the fire monitor water jet landing intensity in the actual experiment, verify the accuracy of the multivariate linear regression equation of the fire monitor water jet landing intensity.

[0018] Preferably, in step 1.1, the structural parameters of the fire monitor include the diameter of the mount and the diameter of the muzzle, and the cross-sectional parameters of the fire monitor include the cross-sectional area of ​​the mount and the cross-sectional area of ​​the muzzle.

[0019] Preferably, the cross-sectional area of ​​the gun mount is calculated according to the gun mount diameter of the fire monitor, as shown in formula (1):

[0020]

[0021] Where A represents the cross-sectional area of ​​the fire monitor mount, in m 2 ; d represents the diameter of the fire monitor's mount, in m.

[0022] Preferably, the muzzle cross-sectional area is calculated according to the muzzle diameter of the fire monitor, as shown in formula (2):

[0023]

[0024] Where A0 represents the muzzle cross-sectional area of ​​the fire monitor, in m 2 ; d0 represents the muzzle diameter of the fire monitor, in m.

[0025] Preferably, in step 1.2, a pressure gauge is provided on the fire cannon mount. Since the pressure loss inside the fire cannon is negligible, the working pressure of the fire cannon is the same as the mount pressure. The working pressure of the fire cannon can be obtained by reading the pressure indication on the fire cannon mount.

[0026] Preferably, in step 1.3, the initial velocity of the water jet at the muzzle of the fire monitor is as shown in formula (3):

[0027]

[0028] Where p represents the working pressure of the fire monitor, in kPa; ρ represents the density of the fluid in the fire monitor, in kg / m 3 ; v represents the velocity of the water jet at the bottom of the fire monitor, in m / s; v0 represents the initial velocity of the water jet at the muzzle of the fire monitor, in m / s.

[0029] Preferably, in step 1.3, when the water jet of the fire monitor enters the air, the constraint of the water jet by the wall of the fire monitor barrel disappears, and the pressure on the water jet of the fire monitor is completely converted into speed.

[0030] Preferably, in step 1.4, the velocity of the water jet at the bottom of the fire monitor is expressed by formula (4):

[0031]

[0032] Where Q represents the flow rate of the water jet in the fire monitor, in m 3 / s;

[0033] The initial velocity of the water jet at the muzzle of the fire monitor is expressed by formula (5):

[0034]

[0035] Substituting equations (4) and (5) into equation (3), we can obtain the relationship between the water jet flow rate in the fire monitor and the working pressure of the fire monitor, as shown in equation (6):

[0036]

[0037] According to the relationship between the water jet flow rate in the fire monitor and the working pressure of the fire monitor, the initial velocity of the water jet at the muzzle of the fire monitor is calculated, as shown in formula (7):

[0038]

[0039] Preferably, in step 1.5, the calculation formula for the actual landing point intensity of the fire monitor water jet is:

[0040]

[0041] In the formula, r represents the actual landing point intensity of the fire monitor water jet, the unit is m 3 / (m 2 ·s); S represents the actual area of ​​the water jet when it lands, in m 2 ; Q represents the flow rate of the water jet in the fire monitor, in m 3 / s.

[0042] Preferably, in step 1.6, the dimensionless calculation formula of the fire monitor inclination angle is:

[0043]

[0044] In the formula, α represents the elevation angle of the fire monitor, in degrees; θ represents the dimensionless tilt angle;

[0045] The dimensionless calculation formula for the working pressure of fire monitor is:

[0046]

[0047] Where, p represents the working pressure of the fire monitor, in kPa; p 标 represents standard atmospheric pressure, p 标 =101kPa; P represents the dimensionless working pressure;

[0048] The dimensionless calculation formula for the initial velocity of the water jet at the muzzle of the fire monitor is:

[0049]

[0050] In the formula, Re represents the dimensionless initial velocity of the water jet; μ represents the viscosity of the fluid in the fire monitor, in Pa·s; the dimensionless calculation formula for the actual landing point intensity of the fire monitor water jet is:

[0051]

[0052] Where R represents the dimensionless intensity of the water jet falling point of the fire monitor.

[0053] Preferably, in step 2, the relationship between the parameters of the fire monitor is as shown in formula (13):

[0054] R = a Re b θ c P d (13)

[0055] In the formula, a, b, c, and d are regression coefficients;

[0056] Based on the multivariate linear regression method, by taking the logarithm of both ends of equation (13), we get:

[0057] ln R=ln a+bln Re+c lnθ+d ln P+ε (14)

[0058] In the formula, ε represents the error;

[0059] Let y = ln R, γ = ln a, x1 = ln Re, x2 = lnθ, x3 = ln P, and the calculation formula of the water jet landing point intensity of the fire monitor based on multivariate linear regression is:

[0060] y=γ+bx1+cx2+dx3+ε (15)

[0061] In the formula, the regression coefficients γ, b, c, and d are determined by multiple linear regression analysis.

[0062] Preferably, in step 3, according to the structural parameters of the fire cannon, the working pressure and the initial velocity of the water jet at the muzzle of the fire cannon in the experiment, the predicted value of the fire cannon water jet landing intensity is calculated using the multivariate linear regression equation of the fire cannon water jet landing intensity, and then combined with the measured value of the fire cannon water jet landing intensity, the average absolute error between the predicted value and the measured value is calculated.

[0063] Preferably, the mean absolute error calculation formula is as follows:

[0064]

[0065] Where N is the total number of measured data points; r i Represents the predicted value corresponding to the i-th data point; r iexp represents the measured value of the i-th data point; MAE represents the mean absolute error between the predicted value and the measured value of the water jet landing intensity of the fire monitor.

[0066] Beneficial technical effects brought by the present invention:

[0067] The present invention proposes a method for calculating the intensity of water jets from fire cannons based on multiple linear regression. The method takes the structural parameters of the fire cannon, the working pressure and the initial velocity of the water jet at the muzzle of the fire cannon as independent variables, takes the intensity of water jets from the fire cannons as dependent variables, and establishes a formula for calculating the intensity of water jets from fire cannons based on the multiple linear regression method, thereby achieving accurate prediction of the intensity of water jets from fire cannons. The present invention fills the technical gap in the field of water jets from fire cannons regarding the method for calculating the intensity of water jets from fire cannons, helps to formulate more accurate firefighting tactics, guide firefighting site work, and lays a foundation for the development of the firefighting field. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 This is a comparison chart of the calculated value and experimental value of the water jet landing point intensity of the fire monitor in this embodiment. DETAILED DESCRIPTION

[0069] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0070] The present invention proposes a method for calculating the intensity of water jet drop points of fire monitors based on multiple linear regression, which specifically includes the following steps:

[0071] Step 1: Dimensionless processing of various parameters of fire monitors, specifically including the following steps:

[0072] Step 1.1, calculate the cross-sectional area of ​​the mount and the cross-sectional area of ​​the muzzle of the fire monitor according to the mount diameter and the muzzle diameter of the fire monitor;

[0073] The calculation formula for the cross-sectional area of ​​the gun mount of a fire monitor is shown in formula (1):

[0074]

[0075] Where A represents the cross-sectional area of ​​the fire monitor mount, in m 2 ; d represents the diameter of the fire monitor’s mount, in m;

[0076] The calculation formula of the muzzle cross-sectional area of ​​the fire monitor is shown in formula (2):

[0077]

[0078] Where A0 represents the muzzle cross-sectional area of ​​the fire monitor, in m 2 ; d0 represents the muzzle diameter of the fire monitor, in m.

[0079] Step 1.2, when the fire monitor is not in use, the gun mount pressure and muzzle pressure of the fire monitor are equal to the atmospheric pressure. A pressure gauge is provided on the gun mount of the fire monitor. The gun mount pressure of the fire monitor is obtained by reading the pressure indication on the gun mount. Since the pressure loss inside the fire monitor is negligible, the working pressure of the fire monitor is the same as the gun mount pressure, and the working pressure of the fire monitor is obtained.

[0080] Step 1.3: When the water jet of the fire monitor is ejected from the muzzle, the constraint of the barrel wall of the fire monitor on the water jet disappears, and the pressure on the water jet of the fire monitor is completely converted into velocity. Based on the Bernoulli equation, the calculation formula for the initial velocity of the water jet at the muzzle of the fire monitor is:

[0081]

[0082] Where p represents the working pressure of the fire monitor, in kPa; ρ represents the density of the fluid in the fire monitor, in kg / m 3 In this embodiment, the fluid in the fire monitor is water, and the density of the fluid in the fire monitor is ρ = 1000 kg / m 3 ; v represents the velocity of the water jet at the bottom of the fire monitor, in m / s; v0 represents the initial velocity of the water jet at the muzzle of the fire monitor, in m / s.

[0083] Step 1.4, based on the structural parameters of the fire monitor and the relationship between the flow rate and flow velocity in the fire monitor, the velocity of the water jet at the bottom of the fire monitor is calculated as:

[0084]

[0085] Where Q represents the flow rate of the water jet in the fire monitor, in m 3 / s;

[0086] The initial velocity of the water jet at the muzzle of the fire monitor is:

[0087]

[0088] Substituting equations (4) and (5) into equation (3), we can obtain the relationship between the water jet flow rate in the fire monitor and the working pressure of the fire monitor, as shown in equation (6):

[0089]

[0090] According to the flow rate of the water jet in the fire monitor, the initial velocity of the water jet at the muzzle of the fire monitor is calculated as:

[0091]

[0092] Step 1.5, according to the flow rate and actual landing area of ​​the fire monitor water jet, calculate the actual landing intensity of the fire monitor water jet, as shown in formula (8):

[0093]

[0094] In the formula, r represents the actual landing point intensity of the fire monitor water jet, the unit is m 3 / (m 2 ·s); S represents the actual area of ​​the water jet when it lands, in m 2 ; Q represents the flow rate of the water jet in the fire monitor, in m 3 / s.

[0095] Step 1.6, respectively, the fire monitor's inclination angle, working pressure, initial velocity of the water jet at the muzzle, and the actual landing intensity of the water jet are dimensionless. During the parameter dimensionless process, the dimensionless calculation formula for the fire monitor's inclination angle is:

[0096]

[0097] In the formula, α represents the elevation angle of the fire monitor, in degrees; θ represents the dimensionless tilt angle;

[0098] The dimensionless calculation formula for the working pressure of fire monitor is:

[0099]

[0100] Where, p represents the working pressure of the fire monitor, in kPa; p 标 represents standard atmospheric pressure, p 标 =101kPa; P represents the dimensionless working pressure;

[0101] The dimensionless calculation formula for the initial velocity of the water jet at the muzzle of the fire monitor is:

[0102]

[0103] Where Re represents the dimensionless initial velocity of the water jet; μ represents the viscosity of the fluid in the fire monitor, in Pa·s; in this embodiment, the fluid in the fire monitor is water, and the fluid viscosity μ=1.005×10 -3 Pa·s, fluid density ρ=1000kg / m 3 ;

[0104] The dimensionless calculation formula for the actual landing point intensity of the fire monitor water jet is:

[0105]

[0106] Where R represents the dimensionless intensity of the water jet falling point of the fire monitor.

[0107] Step 2, by analyzing the dimensionless fire monitor inclination angle, working pressure, actual water jet landing intensity and initial water jet velocity at the muzzle, the functional relationship between the parameters of the fire monitor is determined as follows:

[0108] R = a Re b θ c P d (13)

[0109] In the formula, a, b, c, and d are regression coefficients;

[0110] Based on the multivariate linear regression method, the parameters in formula (13) are analyzed. By taking the logarithm of both ends of formula (13), formula (13) is transformed into a linear regression equation of the form y=xβ+e. After deformation, it is shown in formula (14):

[0111] ln R=ln a+bln Re+c lnθ+d ln P+ε (14)

[0112] In the formula, ε represents the error;

[0113] Therefore, the functional relationship between ln R and ln Re, lnθ, and ln P was determined;

[0114] In formula (14), let y = ln R, γ = ln a, x1 = ln Re, x2 = lnθ, x3 = ln P, and the calculation formula of the water jet impact point intensity of the fire monitor based on multivariate linear regression is obtained as follows:

[0115] y=γ+bx1+cx2+dx3+ε (15)

[0116] In the formula, the regression coefficients γ, b, c, and d are determined by multiple linear regression analysis.

[0117] The regression coefficients in formula (15) are obtained by obtaining the logarithm of the actual landing point strength experimental data of the dimensionless fire monitor water jet under different working conditions, and the logarithm calculation results are substituted into y in the form of a column vector. Then, the logarithm of the dimensionless initial velocity of the water jet at the muzzle, the fire monitor inclination angle, and the fire monitor working pressure are obtained respectively, and the logarithm calculation results are substituted into x1, x2, and x3 in the form of a column vector;

[0118] Import the x1, x2, x3, and y data into MATLAB software, use MATLAB software to process the data, select the regress function in the MATLAB software function library to perform multiple linear regression analysis on the data x1, x2, x3, and y, and obtain the values ​​of the regression coefficients in this embodiment as γ=-23.865, b=1.130, c=-0.0444, and d=-0.883 after multiple linear regression analysis and calculation;

[0119] According to the values ​​of each regression coefficient, the values ​​of each regression coefficient are substituted into formula (14) to determine the multivariate linear regression equation of the water jet landing point intensity of the fire monitor in this embodiment:

[0120] y=-23.865+1.130x1-0.0444x2-0.883x3 (17)

[0121] Therefore, a calculation formula for the intensity of water jet landing point of fire monitors based on multivariate linear regression was established to calculate the predicted value of the intensity of water jet landing point of fire monitors.

[0122] Step 3, based on the predicted value of the fire monitor water jet landing point intensity and the actual fire monitor water jet landing point experimental results, verify the accuracy of the multivariate linear regression equation of the fire monitor water jet landing point intensity.

[0123] Any experimental result determined by measurement means has a certain error. The experimental error is a reflection of whether the experimental measurement result is accurate and reliable. Error analysis is an indispensable part of the accuracy verification of the fire monitor water jet landing intensity calculation method based on the multivariate linear regression method of the present invention. It is an important basis for verifying whether the multivariate linear regression equation of the fire monitor water jet landing intensity established by the method of the present invention is reliable and whether the result is accurate.

[0124] In the actual experiment, according to the structural parameters, working pressure and initial velocity of the water jet at the muzzle of the fire monitor in the experiment, the established multivariate linear regression equation of the water jet landing point intensity of the fire monitor was used to substitute the actual parameter values ​​to calculate the water jet landing point intensity of the fire monitor, and the predicted value of the water jet landing point intensity of the fire monitor was obtained. Combined with the measured value of the water jet landing point intensity of the fire monitor in the experiment, the average absolute error between the predicted value and the measured value of the water jet landing point intensity of the fire monitor was calculated. The calculation formula of the average absolute error between the predicted value and the measured value is as follows:

[0125]

[0126] Where N is the total number of measured data points; r i Represents the predicted value corresponding to the i-th data point; r iexprepresents the measured value of the i-th data point; MAE represents the mean absolute error between the predicted value and the measured value of the water jet landing intensity of the fire monitor.

[0127] The calculation results are as follows Figure 1 As shown, Figure 1 The figure is a comparison chart of the predicted value and measured value of the water jet landing point intensity of the fire monitor, in which the horizontal axis represents the predicted value of the water jet landing point intensity of the fire monitor, and the vertical axis represents the measured value of the water jet landing point intensity of the fire monitor; Figure 1 The results were analyzed and it was found that the measured data points were processed by a fire cannon water jet landing point intensity calculation method based on multivariate linear regression proposed in the present invention, and the predicted value of the fire cannon water jet landing point intensity was calculated to be in good agreement with the experimental value. The average absolute error MAE between the predicted value and the measured value of the fire cannon water jet landing point intensity was 11.3%. The average absolute error calculation result proved that the calculation method proposed in the present invention has good generalization ability and can accurately predict the size of the fire cannon water jet landing point intensity.

[0128] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A method for calculating the intensity of water jets from fire monitors based on multiple linear regression, characterized in that: The specific steps include: Step 1: Dimensionless processing of various parameters of fire monitors, specifically including the following steps: Step 1.1, calculate the cross-sectional parameters of the fire monitor according to the structural parameters of the fire monitor; Step 1.2, obtaining the gun seat pressure of the fire monitor and determining the working pressure of the fire monitor; Step 1.3, based on the Bernoulli equation, determine the calculation formula for the initial velocity of the water jet at the muzzle of the fire monitor; Step 1.4, according to the structural parameters of the fire monitor, using the relationship between the flow rate and the flow velocity in the fire monitor, respectively determine the speed of the water jet at the bottom and the muzzle of the fire monitor, and calculate the initial speed of the water jet at the muzzle of the fire monitor in combination with the working pressure of the fire monitor; Step 1.5, calculating the actual landing point intensity of the fire monitor water jet according to the flow rate and actual landing point area of ​​the fire monitor water jet; Step 1.6, respectively non-dimensionalize the inclination angle, working pressure, initial velocity of the water jet at the muzzle, and actual landing point intensity of the water jet of the fire monitor; Step 2, by analyzing the dimensionless fire monitor inclination angle, working pressure, actual water jet landing intensity and initial water jet velocity at the muzzle, determine the relationship between the parameters of the fire monitor, establish a multiple linear regression equation of the fire monitor water jet landing intensity based on the multiple linear regression method, and calculate the predicted value of the fire monitor water jet landing intensity; Step 3, based on the predicted value of the fire monitor water jet landing point strength and the measured value of the fire monitor water jet landing point strength in the actual experiment, verify the accuracy of the multivariate linear regression equation of the fire monitor water jet landing point strength; In the step 1.1, the structural parameters of the fire monitor include the diameter of the gun seat and the diameter of the gun mouth, and the cross-sectional parameters of the fire monitor include the cross-sectional area of ​​the gun seat and the cross-sectional area of ​​the gun mouth; The cross-sectional area of ​​the fire monitor mount is calculated based on the mount diameter of the fire monitor, as shown in formula (1): Where A represents the cross-sectional area of ​​the fire monitor mount, in m 2 ; d represents the diameter of the fire monitor’s mount, in m; The muzzle cross-sectional area is calculated based on the muzzle diameter of the fire monitor, as shown in formula (2): Where A0 represents the muzzle cross-sectional area of ​​the fire monitor, in m 2 ; d0 represents the muzzle diameter of the fire monitor, in m; In step 1.3, the initial velocity of the water jet at the muzzle of the fire monitor is as shown in formula (3): Where p represents the working pressure of the fire monitor, in kPa; ρ represents the density of the fluid in the fire monitor, in kg / m 3 ; v represents the velocity of the water jet at the bottom of the fire monitor, in m / s; v0 represents the initial velocity of the water jet at the muzzle of the fire monitor, in m / s; In the step 1.3, when the water jet of the fire monitor enters the air, the constraint of the water jet by the wall of the fire monitor barrel disappears, and the pressure on the water jet of the fire monitor is completely converted into speed; In step 1.4, the velocity of the water jet at the bottom of the fire monitor is expressed by formula (4): Where Q represents the flow rate of the water jet in the fire monitor, in m 3 / s; The initial velocity of the water jet at the muzzle of the fire monitor is expressed by formula (5): Substituting equations (4) and (5) into equation (3), we can obtain the relationship between the water jet flow rate in the fire monitor and the working pressure of the fire monitor, as shown in equation (6): According to the relationship between the water jet flow rate in the fire monitor and the working pressure of the fire monitor, the initial velocity of the water jet at the muzzle of the fire monitor is calculated, as shown in formula (7): In step 1.5, the calculation formula for the actual landing point intensity of the fire monitor water jet is: In the formula, r represents the actual landing point intensity of the fire monitor water jet, the unit is m 3 / (m 2 ·s); S represents the actual area of ​​the water jet when it lands, in m 2 ; Q represents the flow rate of the water jet in the fire monitor, in m 3 / s; In step 1.6, the dimensionless calculation formula for the fire monitor inclination angle is: In the formula, α represents the elevation angle of the fire monitor, in degrees; θ represents the dimensionless tilt angle; The dimensionless calculation formula for the working pressure of fire monitor is: Where, p represents the working pressure of the fire monitor, in kPa; p 标 represents standard atmospheric pressure, p 标 =101kPa; P represents the dimensionless working pressure; The dimensionless calculation formula for the initial velocity of the water jet at the muzzle of the fire monitor is: In the formula, Re represents the dimensionless initial velocity of the water jet; μ represents the viscosity of the fluid in the fire monitor, in Pa·s; The dimensionless calculation formula for the actual landing point intensity of the fire monitor water jet is: In the formula, R represents the dimensionless fire monitor water jet impact point intensity; In step 2, the relationship between the parameters of the fire monitor is as shown in formula (13): R=aRe b θ c P d (13) In the formula, a, b, c, and d are regression coefficients; Based on the multivariate linear regression method, by taking the logarithm of both ends of equation (13), we get: lnR=lna+blnRe+clnθ+dlnP+ε (14) In the formula, ε represents the error; Let y = lnR, γ = lna, x1 = lnRe, x2 = lnθ, x3 = lnP, and the calculation formula of the water jet landing point intensity of the fire monitor based on multivariate linear regression is: y=γ+bx1+cx2+dx3+ε (15) In the formula, the regression coefficients γ, b, c, and d are determined by multiple linear regression analysis.

2. The method for calculating the intensity of water jets from fire monitors based on multiple linear regression according to claim 1 is characterized in that: In step 1.2, a pressure gauge is provided on the fire cannon mount. Since the pressure loss inside the fire cannon is negligible, the working pressure of the fire cannon is the same as the mount pressure. The working pressure of the fire cannon is obtained by reading the pressure indication on the fire cannon mount.

3. The method for calculating the intensity of water jets from fire monitors based on multiple linear regression according to claim 1 is characterized in that: In step 3, according to the structural parameters, working pressure and initial velocity of the water jet at the muzzle of the fire monitor in the experiment, the predicted value of the water jet landing point intensity of the fire monitor is calculated using the multivariate linear regression equation of the water jet landing point intensity of the fire monitor, and then combined with the measured value of the water jet landing point intensity of the fire monitor, the average absolute error between the predicted value and the measured value is calculated.

4. The method for calculating the intensity of water jets from fire monitors based on multiple linear regression according to claim 3 is characterized in that: The mean absolute error calculation formula is as follows: Where N is the total number of measured data points; r i Represents the predicted value corresponding to the i-th data point; r iexp represents the measured value of the i-th data point; MAE represents the mean absolute error between the predicted value and the measured value of the water jet landing intensity of the fire monitor.

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