Method, system, medium and equipment for evaluating cooling and pollution control of street trees of urban street canyons

Abstract

The invention discloses a method, a system, a medium and equipment for evaluating cooling and pollution control of street trees of urban street canyons, and the method comprises the steps: constructing a plurality of typical street canyon tree planting models according to meteorological data, street canyon morphological parameters, street tree morphological parameters and road traffic flow data through ENVI-met microclimate simulation software, and carrying out the numerical simulation one by one; performing data processing on the numerical simulation results of the typical street canyon tree planting models, and calculating indexes representing cooling and pollution control hour by hour according to the data processing results; performing normalization according to hourly calculation indexes to obtain a corresponding average value of each index in an evaluation period, and constructing a cooling and pollution control comprehensive evaluation index corresponding to different tree form configurations through an equal weight method. Based on the data processing flow, the comprehensive influence of different forms of street tree planting schemes on street canyon pedestrian area cooling and pollution control is quantitatively evaluated, and an accurate basis is provided for street tree type selection and pruning oriented to street canyon thermal environment and air quality improvement.

Description

Technical Field

[0001] This invention relates to the field of ecological benefit assessment technology for urban street valley greening, and in particular to a method, system, medium and equipment for assessing the cooling and pollution control of street trees in urban street valleys. Background Technology

[0002] With the acceleration of urbanization, the urban heat island effect is becoming increasingly pronounced, leading to more prominent urban high-temperature and air pollution problems, posing a dual threat to human health. Urban street canyons (street valleys) are an important component of the urban underlying surface, playing a vital role in the transportation and daily life of urban residents. The unique spatial structure of street valleys hinders airflow, causing heat and pollutant accumulation, increasing health risks for people living in the canyons. There is an urgent need to improve the environmental quality within street valleys through scientific planning and management measures, thereby reducing health risks for pedestrians. Within the existing urban built environment, the spatial elements of street valleys cannot be easily altered. Street valley greening, as an effective natural solution, offers the dual benefits of regulating the thermal environment and purifying the air.

[0003] Street trees, as part of urban greening, significantly improve the climate of urban valleys by absorbing and reflecting solar radiation and through transpiration. Simultaneously, the adsorption and deposition of pollutants by tree leaves and branches effectively reduces pollutant concentrations; however, the canopy also obstructs airflow, reducing air exchange between the valley interior and the surrounding atmosphere. The regulatory effect of street trees on urban valley thermal comfort and air pollutant dispersion is significantly influenced by morphological characteristics such as tree height, canopy width, and canopy shape, and this influence is further affected by valley morphology and incoming airflow conditions. Clarifying the comprehensive benefits of street trees in cooling and pollution control within specific urban valley environments can provide a valuable reference for planting street trees in urban valleys aimed at improving environmental quality. Currently, there is a lack of feasible methods to comprehensively assess the combined impacts of various types of street trees on pedestrian thermal comfort, ventilation, and pollutant dispersion in different urban valleys. Therefore, in order to better leverage the ecological benefits of street tree greening in improving the environmental quality of urban streets and valleys, there is an urgent need for a method to assess the cooling and pollution control effects of street trees in urban streets and valleys. This method should comprehensively consider the synergistic impact of the built environment, meteorological conditions, and street tree configuration on the thermal environment and air quality, scientifically evaluate the comprehensive ecological benefits of street trees, and provide effective technical support for the selection of street tree species and pruning strategies. Summary of the Invention

[0004] This invention provides a method, system, medium, and equipment for evaluating the cooling and pollution control effects of street trees in urban street valleys. It uses numerical simulation to evaluate the comprehensive benefits of street trees with different morphological characteristics on cooling and pollution control in pedestrian areas of street valleys, thereby assisting in the selection of street tree species and the formulation of tree shaping and pruning strategies, and optimizing the ecological benefits of street trees in improving the environmental quality of street valleys. Firstly, a method for assessing the cooling and pollution control effects of street trees in urban street valleys is provided, including: Acquire meteorological data, street canyon morphological parameters, roadside tree morphological parameters, and road traffic flow data for the target area; Using ENVI-met microclimate simulation software, based on the meteorological data, the street canyon morphology parameters, the roadside tree morphology parameters, and the road traffic flow data, a variety of typical street canyon tree planting models were constructed, and numerical simulations were carried out one by one. The numerical simulation results of various typical street valley tree planting models were processed, and the indicators representing cooling and pollution control were calculated hourly based on the data processing results. After normalizing the hourly calculated indicators, the average value of each indicator for the evaluation period is obtained, and a comprehensive evaluation index for cooling and pollution control corresponding to different tree morphology configurations is constructed using the equal weight method.

[0005] Secondly, an evaluation system for cooling and pollution control of street trees in urban street valleys is provided, including: The data acquisition module is used to acquire meteorological data, street canyon morphological parameters, roadside tree morphological parameters, and road traffic flow data for the target area. The numerical simulation module is communicatively connected to the data acquisition module and is used to construct various typical street valley tree planting models using ENVI-met microclimate simulation software based on the meteorological data, the street valley morphological parameters, the roadside tree morphological parameters, and the road traffic flow data, and to conduct numerical simulations on each of them. The indicator calculation module, communicatively connected to the numerical simulation module, is used to process the numerical simulation results of various typical street valley tree planting models, and to calculate, hourly, indicators characterizing cooling and pollution control based on the data processing results; and, The index evaluation module is connected in communication with the index calculation module. It is used to obtain the average value of each index during the evaluation period after normalizing the index calculated hourly, and to construct a comprehensive evaluation index for cooling and pollution control corresponding to different tree morphology configurations through the equal weight method.

[0006] Thirdly, embodiments of the present invention provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the shield tunnel ring segmentation method based on a linear array camera as described above.

[0007] Fourthly, embodiments of the present invention provide an electronic device, including a storage medium, a processor, and a computer program stored in the storage medium and executable on the processor. When the processor runs the computer program, it implements the method for evaluating urban street tree cooling and pollution control as described above.

[0008] Compared with the prior art, the advantages of the present invention are as follows: 1. This invention combines the impact of street trees on the thermal environment and the diffusion of air pollutants, and establishes an evaluation index system from the two dimensions of cooling and pollution control. This index system considers the degree and scope of the impact of street trees on the thermal comfort and air pollutant diffusion capacity of pedestrian areas, and constructs a comprehensive evaluation index for cooling and pollution control through the equal weight method. It quantitatively evaluates the impact of street trees with different morphological characteristics in various street valleys, and screens street tree morphologies and corresponding tree species that are conducive to improving the environmental quality of street valleys, thereby optimizing the ecological benefits of street trees. This has important theoretical and practical significance for the construction of healthy cities and sustainable development.

[0009] 2. This invention combines street valley morphology parameters with tree morphology parameters to classify urban street valleys and roadside trees, constructs corresponding models, and uses numerical simulation methods for analysis. It comprehensively considers the synergistic effects of meteorological conditions, street valley morphology, and other factors, and quantitatively evaluates the impact of roadside trees with different morphological characteristics on the thermal environment and air quality of pedestrian areas in street valleys. This provides accurate tree species selection and pruning basis for roadside tree planting aimed at improving the street valley environment, and optimizes and enhances the comprehensive ecological benefits of roadside trees through scientific methods. Attached Figure Description

[0010] Figure 1 This is a flowchart illustrating an evaluation method for cooling and controlling pollution from street trees in urban street valleys, according to the present invention. Figure 2 This is a schematic diagram of the tree morphology model constructed in this invention; Figure 3 This is a schematic diagram of the street valley model constructed in this invention. Detailed Implementation

[0011] Referring now to specific embodiments of the invention, examples of which are illustrated in the accompanying drawings. Although the invention will be described in conjunction with specific embodiments, it will be understood that it is not intended to limit the invention to the described embodiments. Rather, it is intended to cover variations, modifications, and equivalents included within the spirit and scope of the invention as defined by the appended claims. It should be noted that the method steps described herein can be implemented by any functional block or functional arrangement, and any functional block or functional arrangement can be implemented as a physical entity or a logical entity, or a combination of both.

[0012] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0013] Note: The examples described below are merely specific examples and are not intended to limit the embodiments of the present invention to the specific steps, values, conditions, data, order, etc. Those skilled in the art can utilize the concept of the present invention to construct more embodiments not mentioned herein by reading this specification.

[0014] Please see Figure 1 The present invention provides a method for evaluating the cooling and pollution control of street trees in urban street valleys, comprising: S100: Acquire meteorological data, street canyon morphological parameters, roadside tree morphological parameters, and road traffic flow data for the target area; S200, using ENVI-met microclimate simulation software, constructs various typical street valley tree planting models based on the meteorological data, street canyon morphological parameters, street tree morphological parameters, and road traffic flow data, and conducts numerical simulations for each, including: S210, based on the meteorological data, the street canyon morphology parameters, the roadside tree morphology parameters and the road traffic flow data, the daily variation data of meteorological parameters for typical meteorological days, the street canyon spatial morphology types, various tree morphology configuration schemes and traffic pollutant emission sources are obtained one by one. Specifically, in this embodiment, the study city area is determined, and a hypothetical small city is taken as the target area.

[0015] Meteorological parameters: Collect meteorological parameters of the target area, including air temperature, relative humidity, wind speed, and wind direction, and compile daily variation data of meteorological parameters for typical meteorological days.

[0016] Street canyon morphological parameters include building height, building layout, road width, building material, road material and street canyon height-to-width ratio, which is the ratio of building height to road width; and determine the typical street canyon spatial morphology type according to the classification method in Table (1).

[0017] Using the street canyon morphology classification table, the street canyon height-to-width ratio in the street canyon morphology parameters is used to determine the street canyon spatial morphology type of the target area, and the street canyon height-to-width ratio value is set during numerical simulation. The street canyon morphology classification table includes: when the street canyon height-to-width ratio is less than 1, the street canyon spatial morphology type is the first type, and the value is set to 0.5 in the numerical simulation; when the street canyon height-to-width ratio is greater than or equal to 1 and less than 2, the street canyon spatial morphology type is the second type, and the value is set to 1.5 in the numerical simulation; when the street canyon height-to-width ratio is greater than or equal to 2, the street canyon spatial morphology type is the third type, and the value is set to 2.5 in the numerical simulation.

[0018] The street valley morphology is classified according to the height-to-width ratio of the street valley, and the specific classification is shown in Table (1).

[0019] Table (1)

[0020] Morphological parameters of roadside trees: Measure the characteristic parameters of common roadside trees in the target area in the field, and record data such as tree species, leaf area index (LAI), tree height, crown width, branch height, and crown shape; organize the data according to the tree morphology classification standard proposed in Table (2) to determine the morphology of each tree.

[0021] By establishing a model relating tree morphology to microclimate response, the morphological parameters of the roadside trees are mapped to a comprehensive influencing factor of street valley ventilation and shading effects, in order to generate different tree morphology configuration schemes with different microclimate regulation capabilities.

[0022] Using the tree morphology-microclimate response relationship model, the values ​​of each parameter during numerical simulation are set according to the morphological parameters of the roadside trees, and the values ​​of each parameter are randomly combined to obtain a variety of tree morphology configuration schemes. The morphological parameters of the roadside trees include leaf area index, crown morphology index, and crown permeability; The tree morphology-microclimate response model includes: when the leaf area index is less than or equal to 3, the value is set to 3 in the numerical simulation; when the leaf area index is greater than 3 and less than or equal to 5, the value is set to 5 in the numerical simulation; when the leaf area index is greater than 5, the value is set to 7 in the numerical simulation; these correspond to weak, medium, and strong solar radiation interception and air filtration capabilities, respectively. The crown morphology index is quantified by the crown height-to-width ratio. When the crown height-to-width ratio is greater than or equal to 1.5, the value is set to 2 in the numerical simulation, which is defined as a compact crown. At this time, the tree height is 15m, the crown width is 6m, and the height under the branches is 3m. When the crown height-to-width ratio is greater than 0.5 and less than 1.5, the value is set to 1 in the numerical simulation, which is defined as a balanced crown. At this time, the tree height is 9m, the crown width is 6m, and the height under the branches is 3m. When the crown width-to-height ratio is less than or equal to 0.5, the value is set to 0.5 in the numerical simulation, which is defined as a spreading crown. At this time, the tree height is 6m, the crown width is 6m, and the height under the branches is 3m.

[0023] Canopy permeability is indirectly defined by the shape of the tree canopy. Oval and conical canopies correspond to high permeability, while spherical and obovate canopies correspond to low permeability, thus reflecting the differences in resistance to the diffusion of pollutants.

[0024] Therefore, the tree morphology is classified according to the individual morphological parameters of the roadside trees, and the values ​​are set for numerical simulation. The specific classification is shown in Table (2): Table (2)

[0025] Road traffic flow data: Traffic flow data of roads corresponding to typical street valley spatial morphology types in the target area are investigated, hourly motor vehicle traffic flow is statistically analyzed, and motor vehicle emission factors are queried to calculate the hourly pollutant emission rate of motor vehicles on the corresponding roads.

[0026] S220, ENVI-met microclimate simulation software was selected as the numerical simulation tool; ENVI-met (Environmental Meteorology) microclimate simulation software was chosen as the numerical simulation tool. ENVI-met mainly includes modules such as Space, ENVI-guide, ENVI-core, Leonardo, and Bio-met, which can input basic parameters, carry out simulations, and visualize simulation results.

[0027] S230, in the ENVI-met microclimate simulation software, the traffic pollutant emission source is set, and a street tree model corresponding to different tree morphology types and a street valley model corresponding to the street valley spatial morphology type are constructed.

[0028] Specifically, in this embodiment, traffic pollutant emission sources in the target area are set in the software database, and the emission height, emission method, and emission rate of the traffic pollutant emission sources are determined. Simultaneously, tree morphology types are determined by freely combining the set values ​​of morphological parameters of common roadside trees, and a custom roadside tree model corresponding to each tree morphology type in the target area is defined; different morphological types of roadside trees are as follows: Figure 2 The 3D model shown. Figure 2 - (1) is a street tree with strong solar radiation interception and air filtration capabilities, a compact canopy, and low light penetration (SCL). The corresponding tree species is sycamore. Figure 2 - (2) Street trees with weak solar radiation interception and air filtration capacity, expansive canopy, and high transparency (WEH) are the corresponding tree species, which is Osmanthus.

[0029] S240, based on the traffic pollutant emission sources, the roadside tree model, and the street valley model, construct multiple typical street valley planting models corresponding to various tree morphological types, and use the daily variation data of the meteorological parameters of the typical meteorological day as boundary conditions in the multiple typical street valley planting models.

[0030] Specifically, based on the traffic pollutant emission sources and street canyon morphological parameters set in the above steps, and combined with the street tree layout pattern in the street canyon model, several typical street canyon planting models corresponding to various tree morphological types are constructed. Each tree morphological type corresponds to one typical street canyon planting model; typical street canyon models are as follows: Figure 3 As shown. Figure 3- (1) is a three-dimensional schematic diagram of a street valley model with a tree morphology of SCL. Figure 3 - (2) is a three-dimensional schematic diagram of the street valley model with tree morphology WEH.

[0031] Finally, in various typical street valley tree planting models, the daily variation data of meteorological parameters on typical meteorological days were used as boundary conditions to set the incoming wind speed, wind direction, air temperature, relative humidity, and urban roughness.

[0032] S250, under the stated boundary conditions, daytime evaluation simulations are performed for each of the various typical street valley tree planting models. Therefore, a 12-hour daytime simulation is conducted under these boundary conditions to obtain hourly street valley air microclimate data and pollutant concentration data for each typical street valley model. Specifically, the boundary conditions are set in the ENVI-guide module.

[0033] S300 processes the numerical simulation results of various typical street valley tree planting models and calculates indicators characterizing cooling and pollution control based on the data processing results, including: For each typical street valley tree planting model, the hourly PET value, wind speed and turbulent kinetic energy are obtained based on human parameters and numerical simulation results during the simulation period. Based on the PET value, the wind speed, and the turbulent kinetic energy, calculate the cooling amplitude and cooling area, which characterize the cooling index, and the roof air exchange rate and high wind speed area ratio, which characterize the pollution control index.

[0034] Specifically, in this embodiment of the invention, software is used to process the numerical simulation results, and the microclimate data and human parameters are imported into the Bio-met module to calculate and obtain the hourly PET (Physiological Equivalent Temperature) for the simulation period. The microclimate data includes air temperature, mean radiation temperature, wind speed and relative humidity; the human parameters include age, gender, weight, height and activity metabolic rate.

[0035] Then, mathematical statistics were performed on the obtained simulation results to obtain basic data of the pedestrian areas on both sides of the motor vehicle lanes inside the street valley on an hourly basis each day. The basic data included average PET, average wind speed, and average turbulent kinetic energy.

[0036] The method for calculating the temperature drop magnitude, which characterizes the cooling index, at each moment is shown in the following formula:

[0037] In the formula, CI represents the temperature drop (°C). For the first in the target area PET difference per grid; PET treei Tree planting in the target area, the first street valley PET values ​​for each grid cell; PETtreefreei For the treeless street valley in the target area The PET value of each grid cell; n is the number of grid cells.

[0038] The method for calculating the cooling area, which represents the cooling index, at each time point is shown in the following formula:

[0039] In the formula, CA represents the cooling area (%). For the first in the target area The PET difference of each grid; T threshld The threshold for PET; The method for calculating the rooftop air exchange rate, which characterizes the pollution control index at each time point, is shown in the following formula:

[0040]

[0041] In the formula, ACH roof Roof air exchange rate, unit is m 3 / s; k A represents the turbulent kinetic energy at the roof level; A represents the area of ​​the roof opening; ACH represents the difference in roof air exchange rate between tree-lined and treeless valleys. ACH roof_tree The rooftop air exchange rate of the tree-planting street valley; ACH roof_treefree The rooftop air exchange rate in treeless street valleys; The method for calculating the high wind speed ratio and area ratio, which characterize the pollution control index at each time point, is shown in the following formula:

[0042] In the formula, VA High wind speed area ratio (%) For the first in the target area The wind speed ratio of each grid; Preset the wind speed at a height of 1.5m under specific wind direction conditions; V 0 represents the initial horizontal wind speed for a pedestrian at a height of 1.5m above the ground, calculated based on meteorological data and the ground roughness coefficient. V threshld The threshold for the wind speed ratio is set to 0.5.

[0043] Therefore, by calculating each indicator within the evaluation period using the above formula, and then normalizing each indicator using the maximum-minimum method, the average value of the simulated period is calculated. The results show that in the street valley with tree morphology SCL, CI is 0.72, CA is 0.37, ACH is 0.47, and VA is 0.51, while in the street valley with tree morphology WEH, CI is 0.70, CA is 0.34, ACH is 0.43, and VA is 0.44.

[0044] S400, using the equal-weighting method, constructs a comprehensive evaluation index to assess the cooling and pollution control corresponding to different tree morphological configurations, including:

[0045] In the formula, CEI is the comprehensive evaluation index of cooling and pollution control corresponding to different tree morphology configurations; CI is the average cooling amplitude; CA is the average cooling area; ACH is the average roof air exchange rate; and VA is the average high wind speed area ratio.

[0046] Therefore, when evaluating the comprehensive benefits of different tree forms in cooling and pollution control, the higher the comprehensive evaluation index, the better the tree form has in cooling and pollution control in this type of street valley.

[0047] Calculations show that the CEI (Chemical Emission Index) of street valleys with tree morphology SCL (Solar Cordless Colour) is 0.51, while that of street valleys with tree morphology WEH (Willow Hair) is 0.48. The results indicate that the comprehensive cooling and pollution control benefits of sycamore are higher than those of osmanthus.

[0048] In summary, the present invention has the following advantages compared with the prior art: 1. This invention combines the impact of street trees on the thermal environment and the diffusion of air pollutants, and establishes an evaluation index system from the two dimensions of cooling and pollution control. This index system considers the degree and scope of the impact of street trees on the thermal comfort and air pollutant diffusion capacity of pedestrian areas, and constructs a comprehensive evaluation index for cooling and pollution control through the equal weight method. It quantitatively evaluates the impact of street trees with different morphological characteristics in various street valleys, and screens street tree morphologies and corresponding tree species that are conducive to improving the environmental quality of street valleys, thereby optimizing the ecological benefits of street trees. This has important theoretical and practical significance for the construction of healthy cities and sustainable development.

[0049] 2. This invention combines street valley morphology parameters with tree morphology parameters to classify urban street valleys and roadside trees, constructs corresponding models, and uses numerical simulation methods for analysis. It comprehensively considers the synergistic effects of meteorological conditions, street valley morphology, and other factors, and quantitatively evaluates the impact of roadside trees with different morphological characteristics on the thermal environment and air quality of pedestrian areas in street valleys. This provides accurate tree species selection and pruning basis for roadside tree planting aimed at improving the street valley environment, and optimizes and enhances the comprehensive ecological benefits of roadside trees through scientific methods.

[0050] This invention also provides an evaluation system for cooling and controlling pollution from street trees in urban street valleys, including: The data acquisition module is used to acquire meteorological data, street canyon morphological parameters, roadside tree morphological parameters, and road traffic flow data for the target area. The numerical simulation module is communicatively connected to the data acquisition module and is used to construct various typical street valley tree planting models using ENVI-met microclimate simulation software based on the meteorological data, the street valley morphological parameters, the roadside tree morphological parameters, and the road traffic flow data, and to conduct numerical simulations on each of them. The indicator calculation module, communicatively connected to the numerical simulation module, is used to process the numerical simulation results of various typical street valley tree planting models, and to calculate, hourly, indicators characterizing cooling and pollution control based on the data processing results; and, The index evaluation module is connected in communication with the index calculation module. It is used to obtain the average value of each index during the evaluation period after normalizing the index calculated hourly, and to construct a comprehensive evaluation index for cooling and pollution control corresponding to different tree morphology configurations through the equal weight method.

[0051] Specifically, this embodiment corresponds one-to-one with the above method embodiments. The functions of each module have been described in detail in the corresponding method embodiments, so they will not be repeated here.

[0052] Based on the same inventive concept, embodiments of this application also provide a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements all or part of the method steps of the above method.

[0053] The present invention can implement all or part of the processes in the above methods, or it can be accomplished by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when the computer program is executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content contained in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0054] Based on the same inventive concept, embodiments of this application also provide an electronic device, including a memory and a processor. The memory stores a computer program that runs on the processor. When the processor executes the computer program, it implements all or part of the method steps described above.

[0055] The processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the computer device, connecting all parts of the computer device through various interfaces and lines.

[0056] Memory can be used to store computer programs and / or modules. The processor performs various functions of the computer device by running or executing the computer programs and / or modules stored in the memory, and by accessing data stored in the memory. Memory can primarily include a program storage area and a data storage area. The program storage area can store the operating system and at least one application program required for a function (e.g., sound playback, image playback, etc.); the data storage area can store data created based on the use of the mobile phone (e.g., audio data, video data, etc.). Furthermore, memory can include high-speed random access memory, and can also include non-volatile memory, such as hard disks, RAM, plug-in hard disks, SmartMedia Cards (SMC), Secure Digital (SD) cards, Flash Cards, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.

[0057] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, servers, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0058] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), servers, and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0059] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0060] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0061] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An evaluation method of urban street canyon street tree cooling and pollution control, characterized in that, The method comprises the following steps: acquiring meteorological data, street canyon shape parameters, street tree shape parameters, and road traffic flow data of a target area; constructing a plurality of typical street canyon tree planting models according to the meteorological data, the street canyon shape parameters, the street tree shape parameters, and the road traffic flow data by using ENVI-met microclimate simulation software, and carrying out numerical simulation one by one; processing the numerical simulation results of the plurality of typical street canyon tree planting models, and calculating indexes representing cooling and pollution control on a time-by-time basis according to the data processing results; obtaining the average values of each index corresponding to the evaluation period after normalizing the time-by-time calculation indexes, and constructing a comprehensive evaluation index of cooling and pollution control corresponding to different tree shape configurations by using an equal weight method.

2. The method of claim 1, wherein the method is for assessing the cooling and pollution control of street trees in urban street canyons. The step of constructing a plurality of typical street canyon tree planting models according to the meteorological data, the street canyon shape parameters, the street tree shape parameters, and the road traffic flow data by using ENVI-met microclimate simulation software, and carrying out numerical simulation one by one comprises the following steps: obtaining daily variation data of meteorological parameters of a typical meteorological day, street canyon spatial shape types, a plurality of tree shape types, and traffic pollutant emission sources one by one according to the meteorological data, the street canyon shape parameters, the street tree shape parameters, and the road traffic flow data; selecting ENVI-met microclimate simulation software as a numerical simulation tool; setting the traffic pollutant emission sources in the ENVI-met microclimate simulation software, constructing street tree models corresponding to different tree shape type configurations, and street canyon models corresponding to the street canyon spatial shape types; constructing a plurality of typical street canyon tree planting models corresponding to a plurality of tree shape types respectively according to the traffic pollutant emission sources, the street tree models, and the street canyon models, and taking the daily variation data of meteorological parameters of the typical meteorological day as boundary conditions in the plurality of typical street canyon tree planting models; carrying out diurnal evaluation period simulation one by one for the plurality of typical street canyon tree planting models under the boundary conditions.

3. The method of claim 2, wherein the method is for assessing the cooling and pollution control of street trees in urban street canyons. determining the street canyon spatial shape types of the target area according to the street canyon height-width ratios in the street canyon shape parameters by using a street canyon shape classification table, and setting the street canyon height-width ratio values during numerical simulation; the street canyon shape classification table comprises: when the street canyon height-width ratio is less than a first ratio threshold value, the street canyon spatial shape type is a first type, and the value is set to a first set value during numerical simulation; when the street canyon height-width ratio is greater than or equal to the first ratio threshold value and less than a second ratio threshold value, the street canyon spatial shape type is a second type, and the value is set to a second set value during numerical simulation; when the street canyon height-width ratio is greater than or equal to the second ratio threshold value, the street canyon spatial shape type is a third type, and the value is set to a third set value during numerical simulation.

4. The method of claim 2, wherein the method is for assessing the cooling and pollution control of street trees in urban street canyons. constructing a tree shape and microclimate response relationship model, setting parameter values during numerical simulation according to the street tree shape parameters by using the tree shape and microclimate response relationship model, and obtaining a plurality of tree shape configuration schemes by randomly combining the parameter values; the street tree shape parameters comprise a leaf area index, a crown shape index, and a crown layer permeability; The method for constructing the tree form-microclimate response model comprises the following steps: The leaf area index comprises three levels of low, medium and high, which correspond to weak, medium and strong solar radiation interception and air filtration capacity, respectively; The crown form index comprises compact, balanced and relaxed; The crown layer permeability comprises high permeability corresponding to spherical and inverse ovoid crown shapes, and low permeability corresponding to ovoid and conical crown shapes.

5. The method of claim 1, wherein the method is for assessing the cooling and pollution control of street trees in urban street canyons. The data processing of the numerical simulation results of the plurality of typical street valley tree planting models is performed, and indexes representing cooling and pollution control are calculated according to the data processing results, comprising: For each typical street valley tree planting model, the PET value, wind speed and turbulent kinetic energy per hour in the simulation period are obtained according to the human body parameters and the numerical simulation results; According to the PET value, the wind speed and the turbulent kinetic energy, the cooling amplitude and the cooling area representing the cooling index at each time, and the roof air exchange rate and the high wind speed area ratio representing the pollution control index at each time are calculated.

6. The method of claim 5, wherein the method is for assessing the cooling and pollution control of street trees in urban canyons. The method for calculating the cooling amplitude representing the cooling index at each time is as follows: In the formula, CI represents the temperature drop. For the first in the target area PET difference per grid; PET treei Tree planting in the target area, the first street valley PET values ​​for each grid cell; PET treefreei For the treeless street valley in the target area The PET value of each grid cell; n is the number of grid cells; The method for calculating the cooling area representing the cooling index at each time is as follows: In the formula, CA is the cooling area; is the PET difference value of the i-th grid in the target region; is the PET difference value of the i-th grid in the target region; T threshld is the threshold value of the PET; The method for calculating the roof air exchange rate representing the pollution control index at each time is as follows: wherein ACH roof is the roof air exchange rate; k is the roof surface turbulent kinetic energy; A is the area of the roof opening surface; ACH is the difference in roof air exchange rate between the tree-lined street canyon and the treeless street canyon; ACH roof_tree is the roof air exchange rate of the tree-lined street canyon; ACH roof_treefree is the roof air exchange rate of the treeless street canyon; The method for calculating the high wind speed area ratio representing the pollution control index at each time is as follows: wherein, VA is the high wind speed ratio area ratio; is the wind speed ratio of the i-th grid in the target area; is the wind speed ratio of the i-th grid in the target area; is the wind speed at the preset height under the specific wind direction condition; V 0 is the horizontal initial wind speed of the pedestrian at the preset distance from the ground; V threshld is the threshold value of the wind speed ratio.

7. The method of claim 1, wherein the method further comprises: determining the temperature of the street tree; and determining the amount of pollution absorbed by the street tree. The comprehensive evaluation index of cooling and pollution control corresponding to different tree form configurations is constructed by the equal weight method, comprising: In the formula, a is a weight coefficient; CEI is the comprehensive evaluation index of cooling and pollution control corresponding to different tree form configurations; CI is the average value of cooling amplitude; CA is the average value of cooling area; ACH is the average value of roof air exchange rate; and VA is the average value of high wind speed area ratio.

8. An evaluation system for urban street canyon street tree cooling and pollution control system, characterized in that, Comprising: The data acquisition module is configured to acquire meteorological data, street valley form parameters, street tree form parameters and road traffic flow data of a target region; The numerical simulation module is in communication connection with the data acquisition module, and is configured to construct a plurality of typical street valley tree planting models according to the meteorological data, the street valley form parameters, the street tree form parameters and the road traffic flow data by using the ENVI-met microclimate simulation software, and perform numerical simulation one by one; The index calculation module is in communication connection with the numerical simulation module, and is configured to perform data processing on the numerical simulation results of the plurality of typical street valley tree planting models, and calculate indexes representing cooling and pollution control according to the data processing results; and The index evaluation module is in communication connection with the index calculation module, and is configured to obtain average values of each index corresponding to an evaluation period after normalization according to the calculated indexes, and construct a comprehensive evaluation index of cooling and pollution control corresponding to different tree form configurations by the equal weight method.

9. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the method for evaluating the cooling and pollution control of street trees in urban street valleys according to any one of claims 1 to 7.

10. An electronic device comprising a storage medium, a processor, and a computer program stored in the storage medium and operable on the processor, characterized in that, The processor executes the computer program to implement the method for evaluating the cooling and pollution control of street trees in urban street valleys according to any one of claims 1 to 7.

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