Icebreaking impact vibration noise load fitting method and device, electronic equipment and storage medium

Abstract

The invention provides an icebreaking impact vibration noise load fitting method and device, electronic equipment and a storage medium, and belongs to the field of icebreaking impact load forecast analysis. The problem that the ice load time-domain curve distribution rule is not obvious and difficult to analyze is solved. The invention discloses an icebreaking impact vibration noise load fitting method. The method comprises the following steps: acquiring a first ice-induced load time-calendar curve with a certain ice thickness and different navigational speeds and a second ice-induced load time-calendar curve with a certain navigational speed and different ice thicknesses; substations are carried out on the first ice-induced load time history curve and the second ice-induced load time history curve; fitting the first ice-induced load frequency domain curve of each station and the second ice-induced load frequency domain curve of each station through an exponential function; performing curved surface fitting on the first function relationship and the second function relationship of each station; using a polynomial curved surface equation to parameterize the relationship between the fitting function coefficient and the navigational speed and the ice thickness to obtain a general formula; and comparing a result obtained by the general formula with a simulation calculation result to verify the effectiveness of the general formula. The method is mainly used for fitting the icebreaking load.

Description

Technical Field

[0001] The present invention belongs to the field of icebreaking impact load prediction and analysis, and in particular relates to an icebreaking impact vibration noise load fitting method, device, electronic equipment and storage medium. Background Art

[0002] Ships are subject to a variety of complex loads during icebreaking, including extrusion failure, shear failure, and bending failure, which are closely related to the physical process of ship-ice interaction. Ice loads have an important impact on the safety and durability of ship structures. Especially in the design and operation of ships operating in ice areas, accurate prediction of ice loads is crucial to ensure ship safety. With the development of computing technology, numerical simulation methods (such as the finite element method) have been able to simulate complex ship-ice interaction processes, providing a reliable data basis for experiments.

[0003] Ice load has the characteristics of temporal and spatial randomness, and its time domain curve distribution law is not obvious, which makes it difficult to simplify and analyze directly. However, there is a certain relationship between load data and speed and ice thickness. In order to obtain the frequency domain trend curve of ice load under any ice thickness and any speed conditions, it is particularly important to develop a fitting method to obtain the trend curve. Summary of the invention

[0004] In view of this, the present invention aims to propose an icebreaking impact vibration noise load fitting method, device, electronic device and storage medium to solve the problem that the distribution law of the ice load time domain curve is not obvious and difficult to analyze.

[0005] To achieve the above object, the present invention adopts the following technical scheme. According to a first aspect of the present invention, a method for fitting icebreaking impact vibration noise load is provided, comprising the following steps:

[0006] The first ice-induced load time history curve at different speeds and the second ice-induced load time history curve at different speeds are obtained from the ice load data between the two extreme working conditions;

[0007] The first ice load time history curve and the second ice load time history curve are divided into stations in the same way, and the first ice load time history curve of each station is processed to obtain the first ice load frequency domain curve of each station, and the second ice load time history curve of each station is processed to obtain the second ice load frequency domain curve of each station;

[0008] The first ice load frequency domain curve and the second ice load frequency domain curve of each station are fitted by exponential function, and the first functional relationship between the first ice load frequency domain fitting function coefficient and the ship speed and the second functional relationship between the second ice load frequency domain fitting function coefficient and the ice thickness are obtained.

[0009] The relationship between the first function relationship of each station and the second function relationship of the corresponding station is fitted to obtain the relationship between the fitting function coefficient and the speed and ice thickness;

[0010] The relationship between the fitting function coefficients and the ship speed and ice thickness is parameterized using polynomial surface equations to obtain a general formula.

[0011] The results obtained by the general formula are compared with the simulation calculation results to verify the validity of the general formula.

[0012] Furthermore, the ice-induced load frequency domain curve is obtained by performing a fast Fourier transform on the ice-induced load time history curve to obtain the ice-induced load frequency domain curve.

[0013] Furthermore, when obtaining the ice-induced load history curve, data whose maximum value is less than a certain proportion of the average maximum load value of the impact load data and / or data whose zero load item is greater than a set threshold are eliminated.

[0014] Furthermore, the substation processing method is to set a station at a certain distance in the X-axis direction.

[0015] Furthermore, the distance is 5m or 10m.

[0016] Furthermore, through the exponential function F = af -b The frequency domain curve of the first ice load at each station is fitted to obtain the relationship between a, b and ship speed. The exponential function y = ax -b The frequency domain curve of the second ice-induced load at each station was fitted to obtain the relationship between a, b and ice thickness, where F and y are loads, f and x are frequencies, and a and b are coefficients.

[0017] Furthermore, the polynomial surface equation is y(v,h)=p00+p10*v+p01*h+p20*v 2 +p11*vh+p02*h 2 +p30*v 3 +p21*v 2 h+p12*vh 2 +p40*v 4 +p31*v 3 h+p22*v 2 h 2 +p50*v 5 +p41*v 4 h+p32*v 3 h 2 , where:

[0018] p00, p10, p01, p20, p11, p02, p30, p21, p12, p40, p31, p22, p50, p41, p32 are constant values, v is the ship speed, and h is the ice thickness.

[0019] According to a second aspect of the present invention, there is provided an icebreaking impact vibration noise load fitting device, comprising:

[0020] A time history curve acquisition module is used to acquire a first ice-induced load time history curve at different speeds with a certain ice thickness and a second ice-induced load time history curve at different speeds with a certain ice thickness from ice load data between two extreme working conditions;

[0021] A substation processing module is used to perform substation processing on the first ice load time history curve and the second ice load time history curve in the same manner, and to process the first ice load time history curve of each station to obtain the first ice load frequency domain curve of each station, and to process the second ice load time history curve of each station to obtain the second ice load frequency domain curve of each station;

[0022] A frequency domain curve fitting module is used to fit the first ice load frequency domain curve and the second ice load frequency domain curve of each station through an exponential function, and obtain the first functional relationship between the frequency domain fitting function coefficient of the first ice load and the ship speed, and the second functional relationship between the frequency domain fitting function coefficient of the second ice load and the ice thickness.

[0023] A surface fitting module is used to fit the first function relationship of each station to the second function relationship of the corresponding station to obtain the relationship between the fitting function coefficient and the speed and ice thickness;

[0024] A general formula acquisition module is used to parameterize the relationship between the fitting function coefficients and the ship speed and ice thickness using a polynomial surface equation to obtain a general formula;

[0025] The verification module is used to compare the results obtained by the general formula with the simulation calculation results to verify the validity of the general formula.

[0026] According to a third aspect of the present invention, there is provided an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the above-mentioned icebreaking impact vibration noise load fitting method.

[0027] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and when the program is executed by a processor, the above-mentioned icebreaking impact vibration noise load fitting method is implemented.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] 1. The fitting method can accurately simulate the complex loads in the ship-ice interaction process based on numerical simulation and experimental data;

[0030] 2. After fitting by this method, the obtained equation can reduce the dependence on field tests, reduce costs and environmental impacts, provide more accurate load data for ship structure design, enhance the safety and reliability of ships sailing in ice areas, and obtain the frequency domain change trend curve of ice load under any ice thickness and any speed conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 It is a flow chart of a method for fitting ice-breaking impact vibration noise load according to the present invention;

[0033] Figure 2 It is a block diagram of an ice-breaking impact vibration noise load fitting device according to the present invention;

[0034] Figure 3 is a schematic structural diagram of the electronic device of the present invention;

[0035] Figure 4 It is a schematic diagram of the location of the substation of the present invention;

[0036] Figure 5 The ice-induced load time history curves for different ship speeds with 1m ice thickness from the first to the fifth station;

[0037] Figure 6 The fitting curves of ice loads at different speeds with 1m ice thickness from the first to the fifth station;

[0038] Figure 7-Figure 11 These are the fitting coefficient curves of ice-induced loads at different speeds with 1m ice thickness from the first to the fifth stations;

[0039] Fig.12 The ice load time history curves of different ice thicknesses at 3kn speed from the first station to the fifth station;

[0040] Fig.13 The fitting curves of ice loads with different ice thicknesses at 3kn speed from the first to the fifth station;

[0041] Figure 14-18 They are the fitting coefficient curves of ice load at different ice thicknesses at 3kn speed from the first station to the fifth station;

[0042] Figure 19-Figure 23 These are the curves of the relationship between the coefficients of the first to fifth stations and the ship speed and ice thickness;

[0043] Fig.24 Finite element model for ice breaking;

[0044] Fig.25 For icebreaker models;

[0045] Fig.26 is the finite element model of the fluid domain;

[0046] Fig. 27 This is the comparison chart between simulation and fitting in the x-direction at a speed of 2.25 kn and an ice thickness of 1.5 m;

[0047] Fig.28 This is a comparison chart between simulation and fitting in the x-direction for a ship speed of 3 kn and an ice thickness of 2.5 m. DETAILED DESCRIPTION

[0048] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0049] The following describes an icebreaking impact vibration noise load fitting method, device, electronic device and storage medium according to an embodiment of the present invention with reference to the accompanying drawings. In view of the problem that the distribution law of the ice load time domain curve is not obvious and difficult to analyze mentioned in the background technology center, the present invention provides an icebreaking impact vibration noise load fitting method. In this method, a surface fitting is performed after fitting the relationship between the fitting coefficient and the speed and the relationship with the ice thickness, and the fitting surface is parameterized by a polynomial to obtain a general formula. In this way, the problem that the distribution law of the ice load time domain curve is not obvious and difficult to analyze is solved.

[0050] Specifically, Figure 1 A schematic flow chart of a method for fitting icebreaking impact vibration noise loads provided in an embodiment of the present invention.

[0051] like Figure 1 As shown, the ice-breaking impact vibration noise load fitting method includes the following steps:

[0052] In step S101, a first ice-induced load time history curve at different speeds and a second ice-induced load time history curve at different speeds are obtained from ice load data between two extreme working conditions;

[0053] Ice load fitting is to obtain ice load curves of different working conditions more quickly. It is necessary to interpolate within a certain working condition. First, ice load data (endpoint data) of two extreme working conditions are obtained, and then a certain number of working conditions are selected within the extreme working conditions to complete the ice load fitting of icebreaking impact load. Then, according to this fitting formula, a fast and accurate prediction of any point in the extreme working condition is achieved, and the effectiveness of the fitting result is verified by numerical simulation calculation to achieve the purpose of promoting and applying the target ship type. The ice-induced impact load data is obtained in the following way: after obtaining the ice-induced impact load data, the data is cleaned; the purpose of cleaning is to remove the ice-induced load with less influence, and take the statistical average of the ice load in the area with the same frequency domain change trend of the ice-induced load, and study its regional change law. Based on this cleaning idea, the impact load with spatiotemporal randomness characteristics is reasonably simplified, the load is preliminarily screened, and the threshold is set. The load with a maximum value less than the threshold or a load zero item greater than the threshold is removed. The threshold is 10% of the average value of all load maximum values ​​and the average number of non-zero items of all loads. The setting method of the threshold is reasonably set according to the requirements.

[0054] Among them, the method of obtaining ice-induced impact load data is to establish a flat ice finite element model based on the elastic fracture failure model with plastic strain failure criterion, and use the LS-Dyna fluid-solid coupling method to carry out numerical simulation of the ice load of the icebreaker model under continuous icebreaking and collision icebreaking to obtain data.

[0055] Specifically, the structure of the icebreaker model is as follows: Fig.25 As shown, the hull material is a rigid body with an elastic modulus of 2.06×10 11 N / m2, Poisson's ratio 0.3. The hull is automatically divided by 2D mesh, the basic unit mesh is about 0.4m, and the number of meshes is 29078. The finite element model of icebreaking is as follows Fig.24 As shown in the figure, all nodes of the hull move at a constant speed in the x direction. In order to ensure that the displacement of the hull finite element model is consistent with the actual hull displacement during icebreaking, the mass points are evenly distributed on the hull finite element model to ensure that the momentum of the hull finite element model is consistent with the actual hull momentum; the length of the ice is about 2 times the length between the vertical lines, the width is about 5 times the width of the ship, and the initial spacing between the flat ice and the water surface is 0.01m. The fluid domain finite element model is shown in the figure. Fig.26As shown in the figure, in order to reasonably reduce the number of grids, the air unit is meshed with variable spacing. The grid in the z direction starts from the free liquid surface and gradually increases towards both ends, which can effectively improve the ALE calculation efficiency. The outer boundary of the flow field (that is, the remaining boundary surfaces except the water-air interface and the bottom of the water area) all use non-reflecting boundary conditions (*BOUNDARY_NON_REFLECTING) to prevent the reflection problem caused by artificial boundary settings, which can achieve the simulation effect of the unbounded flow domain. The non-reflecting boundary condition is set at the top of the air domain to avoid the reverse flow of the fluid after splashing to the top, and to constrain the z-direction degree of freedom of the bottom node of the water area. When modeling, the two are treated as coplanar, and the two materials are shared nodes when dividing the grid. Null material models are used for both water and air.

[0056] The GRUNISE equation of state for water is:

[0057]

[0058] Where p is the medium pressure, ρ0 is the wavefront medium density, μ = ρ / ρ0-1, c is the shock wave velocity (1647 m / s), γ0 is the GRUNISE constant (γ0 = 0.35), b is the first-order volume correction of γ0 (b = 0), S1, S2 and S3 are the state equation coefficients (S1 = 1.92, S2 = -0.096, S3 = 0, respectively).

[0059] The air material model uses a linear polynomial state equation (LINEAR_POLYNOMIAL):

[0060] p=c0+c1μ+c2μ 2 +c3μ 3 +(c4+c5μ+c6μ 2 )E (2)

[0061] Where c0-c6 are the coefficients of the linear polynomial state equation. In this paper, c0=c1=c2=c3=c6=0, c4=c5=0.4, and E=2.5×10 5 .

[0062] The material parameters of the fluid model are shown in Table 1.

[0063] Table 1 Material parameters of fluid model

[0064]

[0065] In order to analyze the characteristics of ice-induced loads in continuous icebreaking, the impact loads of continuous icebreaking were studied under the conditions of a ship speed of 3 kn and a flat ice thickness of 1 m. The table of the impact icebreaking conditions of the icebreaker model is shown in Table 2.

[0066] Table 2 Working conditions

[0067]

[0068] There are three main damage modes when sea ice interacts with the icebreaker model:

[0069] (1) Compression damage: The ice layer is gradually broken due to compression in the affected area;

[0070] (2) Shear failure: cracks are produced when the ice layer is subjected to shear stress that reaches its strength limit;

[0071] (3) Bending failure: The ice layer moves along the inclined structure, then bends and eventually fails.

[0072] Different icebreaking modes will cause changes in the load on the icebreaker model. In general, the ice layer damage mode, ice crack growth process, ice fragments falling off, and ice fragments sliding and clearing phenomena more realistically reflect the icebreaking process of the icebreaker model in a flat ice environment, thus verifying the rationality of this method from the side.

[0073] Therefore, in order to analyze the vibration characteristics of the icebreaker model under the action of ice-induced loads, the nodal forces on the hull surface are output based on the LS-Dyna software to obtain the temporal and spatial distribution of the load of the icebreaker model, as shown in Figure 2. Figure 4 As shown, the yellow represents the position on the hull surface that is subject to the ice-induced impact load. From the numerical results, the stress area of ​​the icebreaker model during the icebreaking process is mainly concentrated near the waterline, that is, the ice-affected zone of the icebreaker model. Therefore, the substation is based on the ice-affected zone. Through the above processing, the load data of the icebreaker can be obtained, and the data can be simplified and distinguished by the above method, which provides a basis for the substation steps.

[0074] In step S102, the first ice load time history curve and the second ice load time history curve are divided into stations in the same manner, and the first ice load time history curve of each station is processed to obtain the first ice load frequency domain curve of each station, and the second ice load time history curve of each station is processed to obtain the second ice load frequency domain curve of each station; the station division method is: a certain distance is set as one station in the X-axis direction, and the certain distance is 5m or 10m. In this application, the partition method is as follows: Figure 4Specifically, from the parallel mid-body of the ship to the area 105m from the tail end, the frequency domain change curves have a high similarity, and 10m is taken as a station to divide this area into two stations: 95m-105m and 85m-95m; from 100m from the stern to the front end of the ship, the ice load is more severe, and 5m is taken as a station, and there are three stations in total: 105m-110m, 110m-115m and 115m-120m. The ice-induced impact load data after cleaning in each station is statistically averaged over time to obtain average processed data; this is used to obtain representative data for the area. Figure 5 As shown in the figure, it can be seen that with the increase of speed, the kinetic energy of the ship breaking ice increases, and the load amplitude at the front end of the bow area (110m-120m) increases with the increase of speed. However, in the 95m-110m area, due to the bending failure mode of PBC at a speed of 3kn, and the phenomenon of large pieces of broken ice falling off, this part of the load has a rapid unloading phenomenon. Therefore, the ice load amplitude under the 3kn working condition in this area is smaller than the corresponding amplitude under the 2.5kn working condition.

[0075] The first ice load time history curve of each station and the second ice load time history curve of each station after averaging are respectively subjected to fast Fourier transform to obtain the first ice load frequency domain curve corresponding to each station and the second ice load frequency domain curve corresponding to each station.

[0076] The fast Fourier transform expression is:

[0077]

[0078] X[k] is the complex representation of the kth frequency component of the sequence x[n].

[0079] x[n] is a discrete signal sequence in the time domain, and n is the index of the sequence, ranging from 0 to N-1.

[0080] N is the length of the sequence x[n].

[0081] k is the frequency index, and its value range is also from 0 to N-1.

[0082] j is an imaginary unit, satisfying j 2 =-1. Fast Fourier transform is an existing technology and is used in an existing manner to convert the time history curve into a frequency domain curve. Figure 5 The ice load time history curves of different ship speeds with 1m ice thickness from the first station to the fifth station are obtained after fast Fourier transform processing, as shown in Figure 6 The frequency domain curves of ice loads at different speeds with 1m ice thickness from the first to the fifth station. Fig.12 The ice load time history curves of different ice thicknesses at 3kn speed from the first station to the fifth station are obtained after fast Fourier transform processing. Fig.13 These are the frequency domain curves of ice-induced loads at different ice thicknesses at 3kn speed from the first to the fifth stations.

[0083] In step S103, the first ice load frequency domain curve and the second ice load frequency domain curve of each station are fitted by exponential functions to obtain a first functional relationship between the first ice load frequency domain fitting function coefficient and the ship speed and a second functional relationship between the second ice load frequency domain fitting function coefficient and the ice thickness.

[0084] Through the exponential function F = af -b The frequency domain average curve of the first ice load at each station is fitted to obtain the relationship between a, b and ship speed. The exponential function y = ax -b The frequency domain average curve of the second ice-induced load at each station was fitted to obtain the relationship between a, b and ice thickness, where F and y are loads, f and x are frequencies, and a and b are coefficients.

[0085] Specifically, using F = af -b Fit the frequency domain curves of ice loads at different speeds and ice thickness of 1 m, and fit the frequency domain functions of ice impact loads in the x direction at different speeds at each station, such as Figure 6 As shown in , in order to obtain the relationship between the ice load frequency domain fitting function coefficient and the ship speed, the ice load frequency domain fitting function coefficients at different speeds are fitted to obtain the relationship between the ice load frequency domain fitting function coefficient and the ship speed, as shown in Figure 7-Figure 11 As shown,

[0086] The first functional relationships are:

[0087] First stop: a = -7720 + 7049*x - 1338*x^2, b = -0.1196 + 0.5675*x - 0.1366*x^2;

[0088] Second stop: a=-4416+3896.4*x-652.8*x^2,b=0.4519-0.0733*x+0.013*x^2;

[0089] The third station: a = -8162 + 7393.1 * x - 1493 * x^2,

[0090] b=-0.4832+0.6981*x-0.1546*x^2;

[0091] The fourth station: a = -4428 + 3865*x-714*x^2,

[0092] b=0.5703-0.3247*x+0.0774*x^2;

[0093] Fifth station: a=1436.1-1348.1*x+349*x^2, b=0.6147-0.4784*x+0.1214*x^2.

[0094] Specifically, using y=ax -b Fitting ice-induced load curves with different ice thicknesses, frequency domain functions of ice-induced impact loads in the x-direction with different ice thicknesses at each station, and ice-induced impact loads in the x-direction with different ice thicknesses at each station are shown in Figure 2. Fig.12 As shown in the figure, in order to obtain the relationship between the ice load frequency domain fitting function coefficient and ice thickness, the ice load frequency domain fitting function coefficients under different ice thicknesses are fitted to obtain the relationship between the ice load frequency domain fitting function coefficient and ice thickness as shown in the figure. Figure 14-18 As shown, the second functional relationships are:

[0095] First stop: a=2567-2246*x+1064*x^2, b=0.5438-0.2793*x+0.089*x^2;

[0096] Second stop: a=4589-5101*x+1910*x^2, b=0.7829-0.6125*x+0.1786*x^2;

[0097] The third station: a = -1156 + 2140*x-404*x^2, b = 0.19 + 0.0323*x-0.0026*x^2;

[0098] The fourth station: a = 1567.9-1319.5*x+492.6*x^2, b = 0.7538-0.6402*x+0.1792*x^2;

[0099] Fifth station: a=1271.34-851.3*x+112.76*x^2, b=0.56838-0.3528*x+0.05832*x^2.

[0100] In step S104, the first function relationship of each station is fitted with the second function relationship of the corresponding station to obtain the relationship between the fitting function coefficient and the speed and ice thickness; the first function of each station is fitted with the function of the corresponding station in the second function, and the surface fitting method is the existing technology and will not be described in detail. Figure 19-Figure 23 , which are the relationship diagrams of the fitting function coefficients, ship speed and ice thickness from the first to the fifth station respectively.

[0101] In step S105, the relationship between the fitting function coefficients and the ship speed and ice thickness is parameterized using a polynomial surface equation to obtain a general formula;

[0102] The polynomial surface equation is: y(v,h)=p00+p10*v+p01*h+p20*v 2+p11*vh+p02*h 2 +p30*v 3 +p21*v 2 h+p12*vh 2 +p40*v 4 +p31*v 3 h+p22*v 2 h 2 +p50*v 5 +p41*v 4 h+p32*v 3 h 2 , where:

[0103] p00, p10, p01, p20, p11, p02, p30, p21, p12, p40, p31, p22, p50, p41, and p32 are constant values, v is the ship speed, and h is the ice thickness. The values ​​are shown in Table 3, where v is the ship speed and h is the ice thickness.

[0104] Table 3

[0105]

[0106]

[0107] In step S106, the results obtained by the general formula are compared with the simulation calculation results to verify the validity of the general formula. Substitute the parameters related to the coefficients a and b of each station into the fitting surface equation, and substitute the speed and ice thickness of the working condition to obtain the coefficients a and b of the fitting curve of each station under specific working conditions. Substitute the coefficients into F=af -b In the figure, the frequency domain variation trend curve of ice load under any ice thickness and any speed condition can be obtained. In order to verify the effectiveness of the fitted surface equation, the simulation results are compared with the results obtained by the surface equation. The working conditions for verifying the effectiveness of the fitting formula are shown in Table 4.

[0108] Table 4 Fitting formula validity verification working condition table

[0109]

[0110] The results are as follows Fig. 27 and Fig.28 In the figure, the blue line shows the actual curve, and the red line shows the fitting curve. The results obtained by the surface equation are basically consistent with the trends and amplitudes of the results obtained by simulation calculation. The method of using the surface equation to calculate the frequency domain variation curve of ice load under any ice thickness and any speed conditions is effective. The comparison between the simulation and fitting in the x-direction of 2.25kn speed and 1.5m ice thickness is shown in the figure. Fig. 27 For 3kn speed and 2.5m ice thickness, the simulation and fitting comparison are as follows: Fig.28,The trends and amplitudes of the results obtained by the prediction and simulation results are basically consistent, and the method of using the surface equation to calculate the frequency domain variation curve of ice load under arbitrary ice thickness and arbitrary ship speed conditions is effective.

[0111] In the above description, the x-axis direction is selected. The analysis process and fitting process of the y-axis and z-axis to obtain the empirical formula method are the same as those of the x-axis direction and will not be repeated here.

[0112] The polynomial surface equation in the y direction is given here as:

[0113] y(v,h)=p00+p10*v+p01*h+p20*v 2 +p11*vh+p02*h 2 +p30*v 3 +p21*v 2 h+p12*vh 2 +p40*v 4 +p31*v 3 h+p22*v 2 h 2 +p50*v 5 +p41*v 4 h+p32*v 3 h 2 , where:

[0114] p00, p10, p01, p20, p11, p02, p30, p21, p12, p40, p31, p22, p50, p41, and p32 are constant values, v is the ship speed, and h is the ice thickness. The values ​​are shown in Table 5. v is the ship speed, and h is the ice thickness.

[0115] Table 5 Parameters of the surface equation in the y direction

[0116]

[0117] p21 p12 p40 p31 p22 p50 p41 p32 9704 -4.96e+4 1.503e+4 -1.222e+4 1.78e+4 -1269 1961 -2086 59 4.815 -1.91 -15.12 -1.078 -0.01478 1.51 0.005526 -4.437e+4 9392 -6614 1.351e+4 -2704 646.6 -1422 233 12.89 1.385 -0.6861 -3.283 -0.2524 0.0007441 0.3284 -0.0003688 -2364 -328.9 -898.9 480.7 -63.47 99.17 -21.31 -10.2 12.13 -1.855 -0.5828 -3.557 0.335 -6.863e-05 0.3557 -2.833e-05 9492 2.563e+4 8738 1297 -1.165e+4 -646.6 -541.6 1643 -0.2491 -1.911 -0.3125 -0.206 0.3342 -0.001821 0.02045 0.0005756 -1.697e+5 9.049e+4 -4.164e+4 5.901e+4 -3.177e+4 3850 -6821 3576 -8.943 1.923 -0.1181 2.828 -0.5061 -0.01294 -0.2833 0.001563

[0118] The polynomial surface equation in the z direction is given here as:

[0119] y(v,h)=p00+p10*v+p01*h+p20*v 2 +p11*vh+p02*h 2 +p30*v 3 +p21*v 2 h+p12*vh 2 +p40*v 4 +p31*v 3 h+p22*v 2 h 2 +p50*v5 +p41*v 4 h+p32*v 3 h 2 Fitting surface, the parameter values ​​are shown in Table 6.

[0120] Table 6 Parameters of surface equation in z direction

[0121]

[0122]

[0123] Secondly, refer to the attached Figure 2 An ice-breaking impact vibration noise load fitting device 200 proposed according to an embodiment of the present invention is described.

[0124] Figure 2 It is a block diagram of an icebreaking impact vibration noise load fitting device according to an embodiment of the present invention.

[0125] like Figure 2 As shown, the ice-breaking impact vibration noise load fitting device comprises:

[0126] A time history curve acquisition module 201 is used to acquire a first ice-induced load time history curve at different speeds with a certain ice thickness and a second ice-induced load time history curve at different speeds with a certain ice thickness from ice load data between two extreme working conditions;

[0127] The substation processing module 202 is used to perform substation processing on the first ice load time history curve and the second ice load time history curve in the same manner, and to process the first ice load time history curve of each station to obtain the first ice load frequency domain curve of each station, and to process the second ice load time history curve of each station to obtain the second ice load frequency domain curve of each station;

[0128] The frequency domain curve fitting module 203 is used to fit the first ice load frequency domain curve of each station and the second ice load frequency domain curve of each station through an exponential function, and obtain the first functional relationship between the frequency domain fitting function coefficient of the first ice load of each station and the ship speed, and the second functional relationship between the frequency domain fitting function coefficient of the second ice load of each station and the ice thickness;

[0129] The surface fitting module 204 is used to fit the first function relationship of each station to the second function relationship of the corresponding station to obtain the relationship between the fitting function coefficient and the speed and ice thickness;

[0130] A general formula acquisition module 205 is used to parameterize the relationship between the fitting function coefficient and the ship speed and ice thickness using a polynomial surface equation to obtain a general formula;

[0131] The verification module 206 is used to compare the result obtained by the general formula with the simulation calculation result to verify the validity of the general formula.

[0132] It should be noted that the above explanation of an embodiment of an icebreaking impact vibration noise load fitting method is also applicable to an icebreaking impact vibration noise load fitting device of this embodiment, which will not be repeated here.

[0133] Figure 3 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. The electronic device may include:

[0134] Memory 401 , processor 402 , and a computer program stored in the memory 401 and executable on the processor 402 .

[0135] When the processor 402 executes the program, an ice-breaking impact vibration noise load fitting method provided in the above embodiment is implemented.

[0136] Furthermore, the electronic device further comprises:

[0137] The communication interface 403 is used for communication between the memory 401 and the processor 402 .

[0138] The memory 401 is used to store computer programs that can be executed on the processor 402 .

[0139] The memory 401 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0140] If the memory 401, the processor 402 and the communication interface 403 are implemented independently, the communication interface 403, the memory 401 and the processor 402 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 3 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0141] Optionally, in a specific implementation, if the memory 401, the processor 402 and the communication interface 403 are integrated on a chip, the memory 401, the processor 402 and the communication interface 403 can communicate with each other through an internal interface.

[0142] The processor 402 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present invention.

[0143] An embodiment of the present invention further provides a computer program product, and when the computer program / instructions are executed by a processor, the above-mentioned icebreaking impact vibration noise load fitting method is implemented.

[0144] An embodiment of the present invention further provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the above-mentioned icebreaking impact vibration noise load fitting method is implemented.

[0145] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0146] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0147] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present invention includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present invention belong.

[0148] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0149] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0150] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0151] In addition, each functional unit in each embodiment of the present invention may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0152] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A method for fitting ice-breaking impact vibration and noise loads, characterized in that: The following steps are involved: The first ice-induced load time history curve at different speeds and the second ice-induced load time history curve at different speeds are obtained from the ice load data between the two extreme working conditions; The first ice load time history curve and the second ice load time history curve are divided into stations in the same way, and the first ice load time history curve of each station is processed to obtain the first ice load frequency domain curve of each station, and the second ice load time history curve of each station is processed to obtain the second ice load frequency domain curve of each station; The first ice load frequency domain curve and the second ice load frequency domain curve of each station are fitted by exponential function, and the first functional relationship between the first ice load frequency domain fitting function coefficient and the ship speed and the second functional relationship between the second ice load frequency domain fitting function coefficient and the ice thickness are obtained. The relationship between the first function relationship of each station and the second function relationship of the corresponding station is fitted to obtain the relationship between the fitting function coefficient and the speed and ice thickness; The relationship between the fitting function coefficients and the ship speed and ice thickness is parameterized using polynomial surface equations to obtain a general formula. The results obtained by the general formula are compared with the simulation calculation results to verify the validity of the general formula.

2. The ice breaking impact vibration noise load fitting method according to claim 1 is characterized in that: The ice-induced load frequency domain curve is obtained by performing a fast Fourier transform on the ice-induced load time history curve to obtain the ice-induced load frequency domain curve.

3. The icebreaking impact vibration noise load fitting method according to claim 2 is characterized in that: When obtaining the ice-induced load history curve, data whose maximum value is less than a certain proportion of the average maximum load value of the impact load data and / or data whose zero load item is greater than a set threshold are eliminated.

4. The icebreaking impact vibration noise load fitting method according to claim 1 is characterized in that: The substation processing method is to set a station at a certain distance with the X-axis as the direction.

5. The icebreaking impact vibration noise load fitting method according to claim 4 is characterized by: The distance is 5m or 10m.

6. The icebreaking impact vibration noise load fitting method according to claim 1 is characterized by: Through the exponential function F = af -b The frequency domain curve of the first ice load at each station is fitted to obtain the relationship between a, b and ship speed. The exponential function y = ax -b The frequency domain curve of the second ice-induced load at each station was fitted to obtain the relationship between a, b and ice thickness, where F and y are loads, f and x are frequencies, and a and b are coefficients.

7. The ice-breaking impact vibration noise load fitting method according to claim 1 is characterized by: The polynomial surface equation is y(v,h)=p00+p10*v+p01*h+p20*v 2 +p11*vh+p02*h 2 +p30*v 3 +p21*v 2 h+p12*vh 2 +p40*v 4 +p31*v 3 h+p22*v 2 h 2 +p50*v 5 +p41*v 4 h+p32*v 3 h 2 , where: p00, p10, p01, p20, p11, p02, p30, p21, p12, p40, p31, p22, p50, p41, p32 are constant values, v is the ship speed, and h is the ice thickness.

8. An ice-breaking impact vibration noise load fitting device, characterized in that: include: A time history curve acquisition module is used to acquire a first ice-induced load time history curve at different speeds with a certain ice thickness and a second ice-induced load time history curve at different speeds with a certain ice thickness from ice load data between two extreme working conditions; A substation processing module is used to perform substation processing on the first ice load time history curve and the second ice load time history curve in the same manner, and to process the first ice load time history curve of each station to obtain the first ice load frequency domain curve of each station, and to process the second ice load time history curve of each station to obtain the second ice load frequency domain curve of each station; A frequency domain curve fitting module is used to fit the first ice load frequency domain curve and the second ice load frequency domain curve of each station through an exponential function, and obtain the first functional relationship between the frequency domain fitting function coefficient of the first ice load and the ship speed, and the second functional relationship between the frequency domain fitting function coefficient of the second ice load and the ice thickness. The surface fitting module is used to fit the first function relationship of each station with the second function relationship of the corresponding station to obtain the relationship between the fitting function coefficient and the speed and ice thickness; A general formula acquisition module is used to parameterize the relationship between the fitting function coefficients and the ship speed and ice thickness using a polynomial surface equation to obtain a general formula; The verification module is used to compare the results obtained by the general formula with the simulation calculation results to verify the validity of the general formula.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the method according to claims 1-7.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and the computer program is used to make the computer execute the method according to claims 1-7.

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