Inversion method, system and computer equipment for raindrop collision results of Meiyu front precipitation

Abstract

The present invention provides an inversion method, system and computer equipment for the collision results of raindrops in Meiyu front precipitation, which obtains multi-source observation data of raindrops and determines raindrop spectrum data; according to the raindrop spectrum data, the spontaneous breakup data of raindrops within a set height range is determined; according to the spontaneous breakup data, raindrops that meet the set collision rate threshold are determined, and their collision kinetic energy and surface potential energy are calculated; according to the collision kinetic energy and the surface potential energy, the raindrop collision results are obtained. Based on multi-source observation means, the present invention can fill the gap in the quantitative study of raindrop microphysical processes in Meiyu front precipitation, and provide technical support for further exploring the evolution mechanism of Meiyu front precipitation.

Description

Technical Field

[0001] The invention relates to the field of atmospheric science and technology, and in particular to an inversion method, system and computer equipment for raindrop collision results of plum rain front precipitation. Background Art

[0002] The study of Meiyu front precipitation has always been a hot topic in the field of atmospheric science. Meiyu front precipitation is an important source of water vapor in the middle and lower reaches of the Yangtze River in my country. Its heavy rain process has caused countless flood disasters and losses of life and property. In past studies, through the implementation of many years of field scientific experiments on heavy rain in the middle and lower reaches of the Yangtze River, the three-dimensional spatial structure data of heavy rain were obtained using various observation methods such as meteorological satellites, radars, and GPS soundings, laying a solid research foundation for the study of heavy rain mechanisms, early warning and forecasting. Although a lot of research has been done on the dynamics, thermal and cloud physical processes of Meiyu front precipitation from meteorological analysis and numerical models, it has been found that Meiyu front precipitation can be formed by warm cloud processes, among which the collision and merging process of rainwater and cloud water is the main one. With the continuous development of new detection equipment, more and more equipment can capture raindrop information, such as two-dimensional video raindrop spectrum, light rain radar, etc., which can provide raindrop diameter, falling speed, number concentration and shape, etc. These information provide strong support for further exploration of the growth changes of raindrops in precipitation clouds and precipitation mechanisms. However, in the existing technology, there is still a blank algorithm for the results of raindrop collision during the Meiyu front precipitation process, which cannot provide support for further improving the heavy rain monitoring, early warning and forecasting capabilities. Summary of the invention

[0003] The present invention provides an inversion method, system and computer equipment for raindrop collision results of Meiyu front precipitation. Based on multi-source observation means, it can fill the gap in quantitative research on raindrop microphysical processes in Meiyu front precipitation and provide technical support for further exploring the evolution mechanism of Meiyu front precipitation.

[0004] The present invention provides an inversion method for the collision results of raindrops in plum rain front precipitation, comprising:

[0005] Obtain multi-source observation data of raindrops and determine the raindrop spectrum data;

[0006] Determining the spontaneous breakup data of raindrops within a set height range according to the raindrop spectrum data;

[0007] According to the spontaneous breakup data, raindrops meeting a set collision rate threshold are determined, and their collision kinetic energy and surface potential energy are calculated;

[0008] A raindrop collision result is obtained according to the collision kinetic energy and the surface potential energy.

[0009] Furthermore, the obtaining of multi-source observation data of raindrops includes:

[0010] Multi-source observation data of raindrops are obtained based on two-dimensional video raindrop spectrometer and light rain radar.

[0011] Furthermore, the step of obtaining multi-source observation data of raindrops and determining raindrop spectrum data includes:

[0012] Acquire multi-source observation data of raindrops, retain the data that meets the set conditions, and determine the raindrop spectrum data.

[0013] Furthermore, the data that meets the set conditions is retained, including:

[0014] Keep the data with total raindrop count or precipitation rate higher than the set value.

[0015] Furthermore, the step of determining the spontaneous breakup data of raindrops within a set range from the ground according to the raindrop spectrum data includes:

[0016] Determining raindrops that meet the spontaneous breakup setting conditions according to the raindrop spectrum data;

[0017] Substitute the raindrop spectrum data of raindrops that meet the spontaneous breakup setting conditions into the spontaneous breakup calculation formula to determine the spontaneous breakup data of raindrops within the set range from the ground.

[0018] Furthermore, the step of determining raindrops meeting a set collision rate threshold according to the spontaneous breakup data and calculating their collision kinetic energy and surface potential energy includes:

[0019] According to the spontaneous breakup data, updating raindrop data within a set height range;

[0020] Obtain a set number of theoretical raindrops, calculate the collision rate between the theoretical raindrops and all raindrops within the set height range after update, and obtain raindrops with a collision rate higher than a threshold value, which are recorded as high collision rate raindrops;

[0021] Calculate the collision kinetic energy and surface potential energy between raindrops with high collision rate in each altitude layer.

[0022] Further, obtaining the raindrop collision result according to the collision kinetic energy and the surface potential energy includes:

[0023] According to the ratio of the collision kinetic energy to the surface potential energy, a raindrop collision result is obtained, and the raindrop collision result includes merging, breaking and rebounding.

[0024] The present invention also provides an inversion system for the collision results of raindrops in the plum rain front precipitation, comprising:

[0025] A data acquisition unit, used to acquire multi-source observation data of raindrops and determine raindrop spectrum data;

[0026] The inversion calculation unit is used to determine the spontaneous breakup data of raindrops within a set height range according to the raindrop spectrum data; determine the raindrops that meet the set collision rate threshold according to the spontaneous breakup data, and calculate their collision kinetic energy and surface potential energy; and obtain the raindrop collision result according to the collision kinetic energy and the surface potential energy.

[0027] The present invention also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the inversion method of the plum rain front precipitation raindrop collision result are implemented.

[0028] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the inversion method for the plum rain front precipitation raindrop collision result is implemented.

[0029] The inversion method, system and computer equipment for the Meiyu front precipitation raindrop collision results provided by the present invention can fill the gap in the quantitative study of the raindrop microphysical process in the Meiyu front precipitation based on multi-source observation means, and provide technical support for further exploring the evolution mechanism of Meiyu front precipitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 It is a flow chart of the inversion method of the plum rain front precipitation raindrop collision result provided by the present invention;

[0032] Figure 2 It is a structural schematic diagram of the inversion system of the plum rain front precipitation raindrop collision result provided by the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In one embodiment, Figure 1 As shown, the present invention provides an inversion method for the collision results of raindrops in the plum rain front precipitation, comprising:

[0035] S100, obtaining multi-source observation data of raindrops and determining raindrop spectrum data; specifically, the raindrop spectrum data includes precipitation particle size, falling speed, and number of particles.

[0036] S200: Determine the spontaneous breakup data of raindrops within a set height range according to the raindrop spectrum data.

[0037] S300: determining raindrops meeting a set collision rate threshold according to the spontaneous breakup data, and calculating their collision kinetic energy and surface potential energy.

[0038] S400: Obtain a raindrop collision result according to the collision kinetic energy and the surface potential energy.

[0039] As an optional embodiment, the obtaining of multi-source observation data of raindrops includes:

[0040] Multi-source observation data of raindrops are obtained based on two-dimensional video raindrop spectrometer and micro-rain radar. Specifically, two-dimensional video raindrop spectrometer and micro-rain radar can be set up by yourself to obtain multi-source observation data of raindrops, or two-dimensional video raindrop spectrometer and micro-rain radar data can be extracted from meteorological stations. The data obtained by the two-dimensional video raindrop spectrometer is in minutes. In order to maintain consistency, the micro-rain radar data is also processed into minute data in minutes.

[0041] As an optional embodiment, the acquiring multi-source observation data of raindrops and determining raindrop spectrum data includes:

[0042] Acquire multi-source observation data of raindrops, retain data that meets the set conditions, and determine the raindrop spectrum data. Perform quality control on the multi-source observation data of raindrops and eliminate unqualified data to ensure the accuracy of subsequent data.

[0043] Based on the above embodiment, as an optional embodiment, the retaining of data meeting the set conditions includes:

[0044] The data with the total number of raindrops or precipitation rate higher than the set value are retained. The method of Tokay et al. (2013) can be used to perform quality control on the 2D video raindrop spectrum data, that is, for every 1 minute of drop spectrum data, if the total number of raindrops is less than 10 or the precipitation rate is less than 0.1 mm h -1 , then the minute data is discarded, otherwise it is retained. To maintain consistency, the light rain radar data is also processed into minute data. If the precipitation rate detected by the raindrop spectrum at the corresponding moment of the light rain radar data is less than 0.1 mm h -1 , then remove the data.

[0045] As an optional embodiment, determining the spontaneous breakup data of raindrops within a set range from the ground according to the raindrop spectrum data includes:

[0046] According to the raindrop spectrum data, raindrops that meet the spontaneous breakup setting conditions are determined; although the phenomenon of spontaneous breakup of raindrops is relatively rare in nature, spontaneous breakup exists when the raindrops exceed 3mm. Therefore, in order to more realistically invert the collision process of raindrops in precipitation, the present invention considers the degree of spontaneous breakup of raindrops in the height range of 0-3km. The spontaneous breakup setting condition is set to an effective diameter / diameter of raindrops greater than 3mm, so as to screen out raindrops that may spontaneously break up.

[0047] Substitute the raindrop spectrum data of raindrops that meet the spontaneous breakup setting conditions into the spontaneous breakup calculation formula to determine the spontaneous breakup data of raindrops within the set range from the ground.

[0048] The calculation formula for spontaneous fragmentation is shown in formula (1):

[0049]

[0050] Where U is the falling speed of the raindrop, D is the diameter, and ρ a and σ are the air density and surface water vapor pressure, respectively.

[0051] As an optional embodiment, determining raindrops meeting a set collision rate threshold according to the spontaneous breakup data, and calculating the collision kinetic energy and surface potential energy thereof, includes:

[0052] According to the spontaneous breakage data, the raindrop data within the set height range is updated; the height range is set to 0-3km. In order to invert more realistically, the present invention considers whether the raindrops will spontaneously break and the impact of spontaneous breakage on the number of raindrops within the height range of 0-3km, and then updates the raindrop data.

[0053] Get a set number of theoretical raindrops, calculate the collision rate between the theoretical raindrops and all raindrops within the updated set height range, and obtain raindrops that are higher than the collision rate threshold, which are recorded as high collision rate raindrops; in this embodiment, the number of theoretical raindrops is 30, which is derived from wind tunnel tests, and the results are close to real raindrops in nature. Based on the detection results of nearly 70 years, the following 30 theoretical raindrops are selected, as shown in Table 1.

[0054] Table 1 Diameters and falling velocities of 30 theoretical raindrops (TR)

[0055]

[0056] After understanding the degree of spontaneous breakup of raindrops, we need to calculate the collision rate of 30 theoretical raindrops with all raindrops at an altitude of 0-3km. Since a high collision rate can promote the occurrence and maintenance of precipitation during heavy precipitation, the collision rate is divided into two groups for raindrops with high collision rates: high collision and low collision. The main calculation method is as follows:

[0057]

[0058] Where CR is the collision rate, N(D) is the number concentration of raindrops of different sizes, k(D,D e ) is the collision nucleus, D e Equivalent diameter. The calculation method of the collision core is shown in formula (3):

[0059]

[0060] Among them, ΔU(D,D e ) is the difference in the falling speed of the two raindrops, E(D,D e ) is the collision efficiency between two raindrops.

[0061] Calculate the collision kinetic energy and surface potential energy between raindrops with high collision rate in each altitude layer.

[0062] The collision kinetic energy CKE and surface potential energy SE of raindrops can be calculated using formulas (4)-(6):

[0063]

[0064]

[0065]

[0066] In the formula, ρ is the density of water, d1 and d2 represent the diameters of the two raindrops, △V is the difference in falling speed between the two raindrops, SE1 and SE2 represent the steady states of the two raindrops, and σ is the water vapor pressure on the droplet surface.

[0067] Based on the above embodiment, as an optional embodiment, obtaining the raindrop collision result according to the collision kinetic energy and the surface potential energy includes:

[0068] According to the ratio of the collision kinetic energy to the surface potential energy, a raindrop collision result is obtained, and the raindrop collision result includes merging, breaking and rebounding.

[0069] Specifically, if CKE / SE1<1 and CKE / SE2>1, it indicates that the raindrop collision is mainly merging and breaking; if CKE / SE1>1, it indicates that the raindrop collision is mainly breaking; if CKE / SE2<1, it indicates that the raindrop collision is mainly rebounding.

[0070] After obtaining the individual raindrop collision results, the proportions of all raindrop collisions, breakups, and rebounds can also be counted.

[0071] like Figure 2 As shown, the present invention also provides an inversion system for the collision results of raindrops in the plum rain front precipitation, comprising:

[0072] A data acquisition unit, used to acquire multi-source observation data of raindrops and determine raindrop spectrum data;

[0073] The inversion calculation unit is used to determine the spontaneous breakup data of raindrops within a set height range according to the raindrop spectrum data; determine the raindrops that meet the set collision rate threshold according to the spontaneous breakup data, and calculate their collision kinetic energy and surface potential energy; and obtain the raindrop collision result according to the collision kinetic energy and the surface potential energy.

[0074] The present invention also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the inversion method of the plum rain front precipitation raindrop collision result are implemented.

[0075] The present invention also provides a computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the inversion method for the plum rain front precipitation raindrop collision result is implemented.

[0076] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0077] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for inverting the collision results of raindrops from plum rain front precipitation, characterized in that: include: Obtain multi-source observation data of raindrops and determine the raindrop spectrum data; Determining the spontaneous breakup data of raindrops within a set height range according to the raindrop spectrum data; According to the spontaneous breakup data, raindrops meeting a set collision rate threshold are determined, and their collision kinetic energy and surface potential energy are calculated; A raindrop collision result is obtained according to the collision kinetic energy and the surface potential energy.

2. The inversion method of the plum rain front precipitation raindrop collision result according to claim 1 is characterized in that: The step of obtaining multi-source observation data of raindrops includes: Multi-source observation data of raindrops are obtained based on two-dimensional video raindrop spectrometer and light rain radar.

3. The inversion method of the plum rain front precipitation raindrop collision result according to claim 1 or 2 is characterized in that: The step of obtaining multi-source observation data of raindrops and determining raindrop spectrum data includes: Acquire multi-source observation data of raindrops, retain the data that meets the set conditions, and determine the raindrop spectrum data.

4. The inversion method of the plum rain front precipitation raindrop collision result according to claim 3 is characterized in that: The data that is retained and meets the set conditions includes: Keep the data with total raindrop count or precipitation rate higher than the set value.

5. The inversion method of the plum rain front precipitation raindrop collision result according to claim 1 is characterized in that: Determining the spontaneous breakup data of raindrops within a set range from the ground according to the raindrop spectrum data includes: Determining raindrops that meet the spontaneous breakup setting conditions according to the raindrop spectrum data; Substitute the raindrop spectrum data of raindrops that meet the spontaneous breakup setting conditions into the spontaneous breakup calculation formula to determine the spontaneous breakup data of raindrops within the set range from the ground.

6. The inversion method of the raindrop collision result of the plum rain front precipitation according to claim 1 is characterized in that: The step of determining raindrops meeting a set collision rate threshold according to the spontaneous breakup data and calculating the collision kinetic energy and surface potential energy thereof comprises: According to the spontaneous breakup data, updating raindrop data within a set height range; Obtain a set number of theoretical raindrops, calculate the collision rate between the theoretical raindrops and all raindrops within the set height range after update, and obtain raindrops with a collision rate higher than a threshold value, which are recorded as high collision rate raindrops; Calculate the collision kinetic energy and surface potential energy between raindrops with high collision rate in each altitude layer.

7. The inversion method of the plum rain front precipitation raindrop collision result according to claim 1 or 6, characterized in that: The step of obtaining a raindrop collision result according to the collision kinetic energy and the surface potential energy includes: According to the ratio of the collision kinetic energy to the surface potential energy, a raindrop collision result is obtained, and the raindrop collision result includes merging, breaking and rebounding.

8. An inversion system for raindrop collision results of plum rain front precipitation, characterized in that: include: A data acquisition unit, used to acquire multi-source observation data of raindrops and determine raindrop spectrum data; An inversion calculation unit, used to determine the spontaneous breakup data of raindrops within a set height range according to the raindrop spectrum data; According to the spontaneous breakup data, raindrops meeting a set collision rate threshold are determined, and their collision kinetic energy and surface potential energy are calculated; and according to the collision kinetic energy and the surface potential energy, raindrop collision results are obtained.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method for inverting the collision results of raindrops of plum rain front precipitation as described in any one of claims 1-2 and 4-6 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the inversion method for the collision results of raindrops of plum rain front precipitation as described in any one of claims 1-2 and 4-6 is implemented.

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