Simulation methods, devices and equipment for solar ground source heat pump systems

Abstract

This invention provides a simulation method, apparatus, and equipment for a solar ground source heat pump system. The simulation method includes: for each borehole in at least one borehole: determining the distance information of any soil point within a predetermined soil region outside the borehole wall from the borehole; based on the distance information, obtaining the unit step response function corresponding to the arbitrary soil point from a pre-built database; calculating the historical step heat load, simulation duration, and unit step response function corresponding to the arbitrary soil point using the buried pipe heat exchanger installed in the borehole, to obtain the temperature change information caused by the borehole to the arbitrary soil point within the simulation duration; and superimposing the temperature change information corresponding to each borehole in at least one borehole to obtain the total temperature change information of the arbitrary soil point within the simulation duration.

Description

Technical Field

[0001] This invention relates to the interdisciplinary fields of renewable energy utilization, building energy conservation and computational heat transfer, specifically to simulation methods, devices and equipment for solar ground source heat pump systems. Background Technology

[0002] Solar ground source heat pump systems, by synergistically combining solar thermal collection and soil thermal storage characteristics, improve energy conversion efficiency and have significant application value in building energy conservation. However, the dynamic operation of this system is affected by intermittent fluctuations in solar energy and the hysteresis of soil thermal response, leading to complex challenges in system simulation. While existing simulation technologies, such as finite element method (FEM) or computational fluid dynamics (CFD) simulations, offer high accuracy, their computational costs are high, making them unsuitable for long-term analysis. Furthermore, although simplified modeling methods reduce computational complexity by simplifying the heat transfer process, they neglect the spatial gradient characteristics of the soil temperature field, failing to accurately reflect the spatiotemporal distribution of the underground temperature field and resulting in design deviations.

[0003] Therefore, the simulation of solar ground source heat pump systems still faces the problem of balancing computational efficiency and simulation accuracy, and there is an urgent need to develop a simulation method that can effectively coordinate the two. Summary of the Invention

[0004] In view of this, the present invention provides a simulation method, apparatus and equipment for a solar ground source heat pump system.

[0005] One aspect of the present invention provides a simulation method for a solar ground source heat pump system. The solar ground source heat pump system includes at least: a buried pipe heat exchanger and a collector. The buried pipe heat exchanger is buried in the soil through at least one borehole, and the collector is located in an outdoor environment. The simulation method includes: for each of the at least one boreholes: determining the distance information of any soil point in a predetermined soil area outside the borehole wall from the borehole; based on the distance information, obtaining the unit step response function corresponding to the soil point from a pre-constructed database, the database storing the mapping relationship between the location of the soil point and the unit step response function, the unit step response function indicating the temperature change caused by the borehole to the soil point at different durations under a unit step heat load; calculating the historical step heat load, simulation duration, and unit step response function corresponding to the buried pipe heat exchanger of the borehole to obtain the temperature change information caused by the borehole to the soil point within the simulation duration; and superimposing the temperature change information corresponding to each of the at least one boreholes to obtain the total temperature change information of the soil point within the simulation duration.

[0006] The database is pre-built through the following operations: A three-dimensional heat conduction equation is constructed based on the temperature, soil density, specific heat capacity, and thermal conductivity of any soil point in a predetermined soil region; the predetermined soil region is divided into a cubic grid composed of grid points, and time is divided into predetermined time steps; a difference equation is constructed based on the cubic grid composed of grid points, the predetermined time steps, and the three-dimensional heat conduction equation; based on the initial temperature of the predetermined soil region, the outer boundary conditions of the predetermined soil region, the borehole wall boundary conditions of the target borehole, and the unit step heat load of the target borehole, the temperature distribution at different times is solved using the difference equation at predetermined time steps, obtaining the temperature change of each grid point relative to the initial temperature at different times, with the target borehole positioned at the center point of the predetermined soil region; the position of each grid point is determined as the position of a soil point; and a mapping relationship is determined based on the temperature change of each grid point relative to the initial temperature at different times and the position of the soil point, and stored in the database.

[0007] Another aspect of the present invention provides a simulation device for a solar ground source heat pump system, the solar ground source heat pump system comprising at least: a buried pipe heat exchanger and a collector, the buried pipe heat exchanger being buried in the soil through at least one borehole, and the collector being located in an outdoor environment; the simulation device comprising: a determination module, configured to, for each of the at least one borehole: determine the distance information of any soil point located outside the borehole wall within a predetermined soil region from the borehole; based on the distance information, obtain the unit step response function corresponding to the arbitrary soil point from a pre-constructed database, the database storing soil... The mapping relationship between the location of the soil point and the unit step response function, which indicates the temperature change caused by the borehole to the soil point over different durations under a unit step heat load; the historical step heat load, simulation duration, and unit step response function corresponding to any soil point of the buried pipe heat exchanger installed in the borehole are calculated to obtain the temperature change information of any soil point caused by the borehole to any soil point within the simulation duration; the superposition module is used to superimpose the temperature change information corresponding to each borehole in at least one borehole to obtain the total temperature change information of any soil point within the simulation duration.

[0008] The database is pre-built through the following operations: A three-dimensional heat conduction equation is constructed based on the temperature, soil density, specific heat capacity, and thermal conductivity of any soil point in a predetermined soil region; the predetermined soil region is divided into a cubic grid composed of grid points, and time is divided into predetermined time steps; a difference equation is constructed based on the cubic grid composed of grid points, the predetermined time steps, and the three-dimensional heat conduction equation; based on the initial temperature of the predetermined soil region, the outer boundary conditions of the predetermined soil region, the borehole wall boundary conditions of the target borehole, and the unit step heat load of the target borehole, the temperature distribution at different times is solved using the difference equation at predetermined time steps, obtaining the temperature change of each grid point relative to the initial temperature at different times, with the target borehole positioned at the center point of the predetermined soil region; the position of each grid point is determined as the position of a soil point; and a mapping relationship is determined based on the temperature change of each grid point relative to the initial temperature at different times and the position of the soil point, and stored in the database.

[0009] One aspect of the present invention provides an electronic device comprising: one or more processors; and a memory for storing one or more computer programs, wherein the one or more processors execute the one or more computer programs to implement the steps of the simulation method for the solar ground source heat pump system.

[0010] One aspect of the present invention provides a computer-readable storage medium having a computer program or instructions stored thereon, wherein the computer program or instructions, when executed by a processor, implement the steps of the simulation method for the solar ground source heat pump system described above.

[0011] According to embodiments of the present invention, by pre-constructing a database of mapping relationships between soil point locations and unit step response functions, the unit step response function corresponding to any soil point within a predetermined soil region outside the borehole wall can be directly queried, given the distance information from the borehole to any soil point. Based on this, the historical heat load of the buried pipe heat exchanger is processed using the principle of linear superposition, thereby superimposing the temperature contributions from multiple boreholes. This avoids the massive computational burden of repeatedly solving complex partial differential equations at each time step using traditional numerical methods, significantly improving the speed of long-period dynamic simulation. Simultaneously, it accurately reflects the thermal interference effects between multiple boreholes and the spatiotemporal evolution of the soil temperature field, achieving efficient and accurate simulation of the soil temperature field of a solar ground source heat pump system, at least partially solving the problem of balancing computational efficiency and accuracy in simulation. Attached Figure Description

[0012] The above and other objects, features and advantages of the present invention will become clearer from the following description of embodiments of the invention with reference to the accompanying drawings.

[0013] Figure 1A schematic diagram of a solar ground source heat pump system according to an embodiment of the present invention is shown.

[0014] Figure 2 A flowchart illustrating a simulation method for a solar ground source heat pump system according to an embodiment of the present invention is shown.

[0015] Figure 3 A flowchart of a simulation method for a solar ground source heat pump system according to another embodiment of the present invention is shown.

[0016] Figure 4 A schematic diagram of grid points according to an embodiment of the present invention is shown.

[0017] Figure 5 A schematic diagram illustrating the superposition of temperature fields generated by the combined influence of multiple boreholes on any soil point outside the boreholes according to an embodiment of the present invention is shown.

[0018] Figure 6 A block diagram of a simulation device for a solar ground source heat pump system according to an embodiment of the present invention is shown.

[0019] Figure 7 A block diagram of an electronic device suitable for implementing a simulation method for a solar ground source heat pump system according to an embodiment of the present invention is shown. Detailed Implementation

[0020] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the invention for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0021] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0022] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0023] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0024] In realizing the concept of this invention, it was discovered that the interaction of multiple heat sources in a coupled solar and ground source heat pump system further exacerbates the simulation difficulty. The random fluctuations in solar energy input and the cumulative effect of soil thermal response superimpose each other, making it difficult for traditional simulation methods to maintain a balance between accuracy and efficiency in long-term analysis. High-precision methods cannot achieve long-term simulation due to excessive computational costs, while simplified models suffer from insufficient spatial resolution, leading to predictions that deviate from actual operating conditions. This contradiction between computational efficiency and simulation accuracy restricts the optimal design and operational strategy formulation of solar-ground source heat pump systems.

[0025] Based on this, embodiments of the present invention provide a simulation method for a solar ground source heat pump system. The solar ground source heat pump system in this method may include at least: a buried pipe heat exchanger and a collector. The buried pipe heat exchanger can be buried in the soil through at least one borehole, and the collector is installed in the outdoor environment.

[0026] Buried pipe heat exchangers can be in the form of U-shaped tubes or spiral tubes, and can be installed by drilling vertically or horizontally. Fluid circulates in the buried pipe heat exchanger, enabling it to release heat to or absorb heat from the soil.

[0027] The solar collector can be a flat-plate collector or a evacuated tube collector, and it can be installed on the roof or ground of a building. The collector can be used to collect solar radiation energy and convert it into heat energy, providing an auxiliary heat source for solar ground source heat pump systems or for soil heat storage.

[0028] The geometry and depth of the borehole affect the heat exchange performance of the buried pipe heat exchanger.

[0029] Figure 1 A schematic diagram of a solar ground source heat pump system according to an embodiment of the present invention is shown.

[0030] For example, such as Figure 1The solar-geothermal heat pump system shown uses a flat-plate collector and related circulating pumps, such as P1, as the system's priority heat source. During periods of ample sunshine, heat is directly collected and transported to a water tank and connected piping. A distribution network consisting of multiple pumps (such as P2, P3, and P4) and valves (such as V1-V5) flexibly manages the heat flow to supply users or store it in the water tank and underground soil. At night, on cloudy or rainy days, or when heating demand is high and solar energy is insufficient, the system automatically switches to a medium-deep buried pipe heat exchanger as the primary heat source. This heat exchanger, comprising inner and outer pipes and backfill material, extracts heat from the constant-temperature deep soil through a closed-loop circulation. The heat pump unit then raises the temperature to a suitable level before supplying it to the user. The heat pump unit, as the energy boosting and conversion hub of the entire system, raises the temperature of low-temperature heat sources such as solar or geothermal energy to a high level suitable for user heating, ensuring stable heating. This design maximizes the use of free solar energy and enables cross-seasonal heat storage and stable backup through the earth, solving the soil thermal imbalance problem that may occur during the long-term operation of a single ground source heat pump, thus achieving more efficient and sustainable comprehensive utilization of renewable energy.

[0031] The following will be through Figures 2-5 The simulation method of the solar ground source heat pump system according to an embodiment of the present invention is described in detail.

[0032] Figure 2 A flowchart illustrating a simulation method for a solar ground source heat pump system according to an embodiment of the present invention is shown.

[0033] like Figure 2 As shown, the simulation method for this solar ground source heat pump system includes operations S210 to S240.

[0034] In operation S210, the distance information of any soil point in a predetermined soil area outside the borehole wall from the borehole is determined.

[0035] In operation S220, based on distance information, the unit step response function corresponding to any soil point is obtained from a pre-built database.

[0036] In operation S230, the historical step thermal load, simulation duration, and unit step response function corresponding to any soil point of the borehole-buried underground pipe heat exchanger are calculated to obtain the temperature change information caused by the borehole to any soil point within the simulation duration.

[0037] In operation S240, the temperature change information corresponding to each borehole in at least one borehole is superimposed to obtain the total temperature change information of any soil point within the simulation time.

[0038] It should be noted that for each borehole in at least one borehole, operations S210 to S230 need to be repeated.

[0039] In this embodiment, the predetermined soil region can refer to a specific soil area surrounding the borehole that requires temperature field simulation analysis. The physical properties and boundary conditions of this region affect the simulation results.

[0040] Distance information indicates the horizontal distance from any soil point within a predetermined soil area to the borehole axis. This distance information can be obtained by manually measuring the horizontal distance from the soil point to the borehole center, or calculated using the coordinates of a preset fixed grid of points. For example, a coordinate system with the borehole center as the origin can be set up, and the coordinates of each soil point can be manually entered to calculate its distance to the borehole.

[0041] The database stores the mapping relationship between the location of soil points and the unit step response function. For example, before the actual simulation of the system, the mapping relationship between the location of soil points and the unit step response function can be pre-calculated and stored for a single borehole under a unit step thermal load through offline calculations, such as the finite difference method.

[0042] The unit step response function indicates the temperature change at a soil point within a predetermined soil region over different time periods caused by a unit step heat load. For example, it represents the temperature change relative to the initial temperature at any soil point within a predetermined soil region over different time periods when a unit step heat load is applied to the borehole wall. A unit step heat load can be understood as an idealized, constant unit heat input or output applied to the borehole wall, starting at a certain moment.

[0043] Historical step heat load can refer to the actual heat load history of the buried pipe heat exchanger during actual operation, which is discretized into a series of step heat loads with different intensities and durations.

[0044] Simulation duration can refer to the time span for conducting temperature field simulation analysis, such as several hours, several days, or several years.

[0045] Temperature change information can refer to the amount of temperature increase or decrease caused by drilling to any soil point within a predetermined soil area, obtained through calculation, within a specific simulation period.

[0046] Superposition can refer to the algebraic summation of the temperature change information of the same soil point caused by the step thermal load of multiple boreholes or the same borehole at different historical times, based on the principle of linear superposition, in order to obtain the total temperature change of the soil point.

[0047] According to embodiments of the present invention, by pre-constructing a database of mapping relationships between soil point locations and unit step response functions, the unit step response function corresponding to any soil point within a predetermined soil region outside the borehole wall can be directly queried, given the distance information from the borehole to any soil point. Based on this, the historical heat load of the buried pipe heat exchanger is processed using the principle of linear superposition, thereby superimposing the temperature contributions from multiple boreholes. This avoids the massive computational burden of repeatedly solving complex partial differential equations at each time step using traditional numerical methods, significantly improving the speed of long-period dynamic simulation. Simultaneously, it accurately reflects the thermal interference effects between multiple boreholes and the spatiotemporal evolution of the soil temperature field, achieving efficient and accurate simulation of the soil temperature field of a solar ground source heat pump system, at least partially solving the problem of balancing computational efficiency and accuracy in simulation.

[0048] In some of the above-mentioned solutions of the present invention, a simulation method based on the unit step response function is proposed to calculate soil temperature changes. However, in actual operation, due to factors such as the uncertainty of soil thermal properties, thermal interference between boreholes and seasonal heat storage effects, there is a systematic deviation between the pre-constructed unit step response function and the actual thermal response. This deviation will accumulate and amplify in long-term simulation, affecting the accuracy of the simulation results.

[0049] In view of this, another embodiment of the present invention proposes a correction mechanism to address the above-mentioned... Figure 2 Before operating procedure S230, which calculates the historical step thermal load, simulation duration, and unit step response function corresponding to any soil point for the borehole-embedded buried pipe heat exchanger, it may also include, as shown in the example, the following steps. Figure 3 Operations S310 to S340 are shown.

[0050] In operation S310, a reference response function is obtained based on the ratio of the temperature change at any soil point in at least one borehole to the unit step heat load under actual operating conditions.

[0051] In operation S320, the measured response function is determined based on the fluid parameters of each borehole in at least one borehole under actual operating conditions.

[0052] When operating S330, the residual function is obtained based on the difference between the measured response function and the reference response function.

[0053] In operation S340, the unit step response function corresponding to any soil point is corrected based on the residual function.

[0054] In this embodiment, the ratio of temperature change to unit step heat load can reflect the thermal response characteristics exhibited by the soil point under the condition of a fixed unit heat load.

[0055] In one example, a known unit step thermal load can be applied to the borehole during a specific controlled phase of system operation, while simultaneously measuring the temperature change at any soil point within a predetermined soil region. The temperature change at that soil point is then considered the baseline response function.

[0056] In one example, a simplified heat transfer model that has been preliminarily calibrated can be used, for example, based on a simplified numerical model, to calculate the temperature change at any soil point by inputting a unit step heat load, and use it as a baseline response function.

[0057] Fluid parameters may include at least: borehole inlet temperature, outlet temperature, total thermal resistance, effective heat transfer depth, and initial ground temperature.

[0058] The measured response function can reflect the soil's response to actual heat exchange, while fluid parameters can characterize key information about actual heat exchange.

[0059] In one example, during actual system operation, parameters such as the inlet and outlet temperatures of the fluid within the borehole can be continuously monitored, and the actual thermal load of the borehole can be calculated by combining these parameters with fluid flow rate and specific heat capacity. Furthermore, the actual temperature change at any soil point is measured. By correlating the actual temperature change at the soil point with the calculated actual thermal load, for example, through ratio or deconvolution methods, the measured response function can be obtained. The total thermal resistance can be obtained through thermal response testing or calculated based on borehole structure and material parameters. The effective heat transfer depth is a borehole design parameter. The initial ground temperature can be obtained by measuring the ground temperature probe before system operation.

[0060] In one example, the actual measured fluid parameters, such as inlet temperature, outlet temperature, and soil point temperature changes, are input into a parameter-adjustable numerical model. The model parameters are adjusted through an inversion algorithm so that the model output matches the measured data. The response of the model under a unit step heat load can then be regarded as the measured response function.

[0061] The residual function can represent the systematic deviation of a pre-constructed unit step response function in practical applications. This deviation may stem from complex factors such as uncertainties in soil thermal properties, inter-bore thermal interference, or long-term heat storage effects. For example, the residual function can be obtained by directly calculating the difference between the measured response function and the benchmark response function at the same time and spatial location. Alternatively, statistical methods can be used, such as calculating the mean square error or relative error between the two, and using the distribution of these errors over time or space as a function of the residual function.

[0062] In one example, the residual function can be directly superimposed on the original unit step response function to form the modified unit step response function.

[0063] According to embodiments of the present invention, the correction mechanism of the present invention can effectively reduce the deviation between the simulation model and the actual system, thereby improving the accuracy and reliability of long-term simulations. It effectively avoids the problem of cumulative amplification of model deviations in long-term simulations, which is common in traditional methods.

[0064] In some of the above-mentioned solutions of the present invention, total thermal resistance is proposed as a fluid parameter to determine the measured response function and correct the unit step response function. However, in this process, the composition of total thermal resistance is not clearly defined, which may lead to inaccurate calculation of heat transfer resistance, thereby affecting the reliability of response function correction and ultimately reducing the accuracy of soil temperature field simulation.

[0065] In this regard, the borehole includes an inner tube and an outer tube. The total thermal resistance indicates the heat transfer resistance between the fluid inside the borehole and the soil outside the borehole. The total thermal resistance is composed of the fluid convection thermal resistance and the external medium conduction thermal resistance in series.

[0066] According to embodiments of the present invention, by accurately quantifying the heat transfer resistance from the fluid inside the borehole to the external soil, the measured response function determined based on fluid parameters can more realistically reflect the actual heat transfer performance of the buried pipe heat exchanger. This further improves the accuracy of the residual function calculation, thereby making the correction of the unit step response function more reliable and effective.

[0067] In the process of implementing the embodiments of the present invention, it was found that real-time calculation of the unit step response function requires repeated solving of three-dimensional partial differential equations, resulting in high computational resource consumption and low efficiency, making it difficult to support fast long-cycle simulations. In particular, when dealing with multiple boreholes or dynamic thermal loads, the computational burden is further aggravated.

[0068] Based on this, in another embodiment of the present invention, a database can be pre-constructed through the following operations: A three-dimensional heat conduction equation is constructed based on the temperature, soil density, specific heat capacity, and thermal conductivity of any soil point in a predetermined soil region; the predetermined soil region is divided into a cubic grid composed of grid points, and time is divided into predetermined time steps; a difference equation is constructed based on the cubic grid composed of grid points, the predetermined time steps, and the three-dimensional heat conduction equation; based on the initial temperature of the predetermined soil region, the outer boundary conditions of the predetermined soil region, the borehole wall boundary conditions of the target borehole, and the unit step heat load of the target borehole, the temperature distribution at different times is solved using the predetermined time steps to obtain the temperature change of each grid point relative to the initial temperature at different times, with the target borehole positioned at the center point of the predetermined soil region; the position of each grid point is determined as the position of a soil point; a mapping relationship is determined based on the temperature change of each grid point relative to the initial temperature at different times and the position of the soil point, and stored in the database.

[0069] In this embodiment, by introducing thermophysical parameters such as soil temperature, density, specific heat capacity and thermal conductivity, the thermal response characteristics of different soil media can be accurately reflected.

[0070] For example, the three-dimensional unsteady-state heat conduction differential equation can be derived using Fourier's law and the law of conservation of energy, or a set of three-dimensional heat conduction equations can be constructed based on the layered structure or heterogeneity of the actual soil to more precisely describe the differences in the thermophysical properties of soils at different depths or in different regions. The three-dimensional heat conduction equation considers the diffusion of heat in three spatial dimensions and its change over time, as shown in equation (1) below:

[0071] (1)

[0072] in, This indicates soil density, expressed in kg / m³. This indicates specific heat capacity, expressed in J / (kg·K). The coefficient of thermal conductivity is represented by W / (m·K); T represents the soil temperature field in °C; t represents time in seconds; x, y, and z are all spatial coordinates.

[0073] Indicatively, a uniform mesh or a non-uniform mesh can be used. However, using a uniform mesh may result in insufficient mesh resolution in areas with large temperature gradients near the borehole, making it impossible to accurately capture the details of heat conduction and affecting the accuracy of the calculation. At the same time, the mesh may be too dense in areas far from the borehole, resulting in a waste of computational resources and reduced simulation efficiency, making it difficult to balance the accuracy and speed of long-cycle simulations.

[0074] Therefore, in a preferred embodiment of the present invention, the multiple cubic grids within the predetermined soil area are non-uniform grids, and the distance between the grid points and the target borehole is inversely proportional to the volume of the cubic grid.

[0075] For example, this can be achieved by using a hierarchical mesh, where the mesh size gradually increases from the center of the target borehole outwards; or by using a structured non-uniform mesh, where the mesh spacing is controlled by a mathematical function along predefined mesh lines to form cubic cells of different sizes. This allows for the use of a smaller mesh size for refinement in the vicinity of the borehole, while a larger mesh size is used in areas farther away from the borehole, ensuring computational accuracy while optimizing computational resources.

[0076] Figure 4 A schematic diagram of grid points according to an embodiment of the present invention is shown.

[0077] The designated soil region is physically a continuous three-dimensional space, where the location of any point can be determined by three spatial coordinates (x, y, z). This continuous three-dimensional space can be divided into cubic units, for example, using units spaced at intervals of [missing information] along the three coordinate axes (x, y, z). , , The grid is cut by parallel planes. These planes intersect to form a regular cubic grid. The intersections of the grid lines are called nodes or grid points, such as... Figure 4 As shown, points are represented by a longitudinal section of the soil. To calculate each grid point, integer indices (i, j, k) can be introduced to number all grid points, where i represents the grid point's position number in the x-direction, j represents the grid point's position number in the z-direction, and k represents the grid point's position number in the y-direction. Figure 4 Only the grid points (i,j) and (i+1,j+1) of the longitudinal section of the soil are shown. The distance between grid point (i,j) and the borehole center axis is r. i The distance between grid point (i+1, j+1) and the borehole center axis is r. i+1 Grid point (i,j), the depth of grid point (i,j) above the ground in the z direction is z. j The depth of grid point (i+1, j+1) in the z-direction from the ground is z. j+1 .

[0078] For example, an explicit difference scheme can be used, which approximates the differential by using the difference between the values ​​of adjacent grid points. The first-order time derivative is used to characterize the rate of temperature change of the same grid point (i,j,k) at two adjacent times t and t+Δt, where Δt represents a predetermined time step and must satisfy stability conditions. To ensure that heat does not propagate beyond one cubic grid within a time step, thus guaranteeing that the dependency region of the discrete equations includes the dependency region of the continuous equations, we take the x-direction as an example. The rate of change of the temperature distribution along the x-direction at time t is characterized by the second spatial derivative, calculated using the temperature values ​​of grid point (i,j,k) and its two direct neighbors (i+1, j, k) and (i-1, j, k) in the x-direction. For the y and z directions, the form is identical; simply replace i with j or k. Replace with or Therefore, the difference equation can be obtained as shown in equation (2):

[0079] (2)

[0080] Where n represents the number of predetermined time steps; This represents the temperature of grid point (i,j,k) at the (n+1)th predetermined time step. This represents the temperature of grid point (i,j,k) at the time corresponding to the nth predetermined time step; , These represent the temperatures of the two direct neighbors (i+1, j, k) and (i-1, j, k) of grid point (i, j, k) in the x-direction at the time corresponding to the nth predetermined time step, respectively. , These represent the temperatures of the two direct neighbors (i, j+1, k) and (i, j-1, k) of grid point (i, j, k) in the z direction at the time corresponding to the nth predetermined time step, respectively. , These represent the temperatures of the two direct neighbors (i, j, k+1) and (i, j, k-1) of grid point (i, j, k) in the y direction at the time corresponding to the nth predetermined time step.

[0081] For example, the outer boundary condition of the predetermined soil region indicates that when the distance between the soil point and the borehole exceeds a distance threshold, the temperature change of the soil point relative to the initial temperature at different times is zero. The borehole wall boundary condition indicates that the heat flux density conducted from the interior of the borehole wall to the borehole wall is equal to the heat flux density carried away by the fluid inside the borehole from the borehole wall by convection.

[0082] For example, the condition can be set such that there is convective heat transfer between the borehole wall and the fluid, as shown in equation (3) below:

[0083] (3)

[0084] in, This indicates that the temperature T is in the direction normal to the wall. The gradient; Indicates the convective heat transfer coefficient; The temperature of the fluid inside the pipe can be determined by the heat pump's operating parameters; This indicates the temperature of the wall surface.

[0085] Discretize equation (3) as shown in equation (4) below:

[0086] (4).

[0087] The outer boundary conditions can be set as initial conditions or distant boundary conditions.

[0088] Since the difference equations are solved at grid points, each grid point represents the soil properties and temperature of its region. Treating the grid point location directly as the soil point location allows for accurate spatial correlation in subsequent database construction and queries. For example, the center coordinates of the grid point can be used directly as the soil point's location, or its precise location in the global coordinate system can be calculated based on the grid point's index and grid size.

[0089] According to embodiments of the present invention, when dealing with multiple boreholes or dynamic thermal loads, there is no need to repeatedly perform time-consuming numerical simulations. The required unit step response function can be quickly obtained directly based on a pre-built database, which improves the computational efficiency of long-cycle simulation of solar ground source heat pump systems and effectively solves the problem of low efficiency in real-time calculation of unit step response functions.

[0090] In one embodiment, the reference response function It can be shown in the following formula (5):

[0091] (5)

[0092] in, Let r represent the temperature of a soil point at time t, at a distance r from the borehole center and at a depth z from the ground along the z-direction; It represents the initial ground temperature, which can be related to depth, such as the average soil temperature at the borehole depth; This represents the unit step thermal load and can be taken as 1 W / m.

[0093] To reduce deviations caused by uncertainties in soil thermal properties, inter-bore thermal interference, and seasonal heat storage effects during long-term operation, physical consistency corrections can be applied to the offline response function based on the residual function. Residual function As shown in equation (6):

[0094] (6)

[0095] in, The measured response function is shown in equation (7) below:

[0096] (7)

[0097] in, The water inlet temperature of the i-th borehole at time t is expressed in °C. The water temperature at time t represents the temperature of the water exiting the i-th borehole, in °C. This represents the total thermal resistance of the i-th borehole, expressed in m·K / W. This represents the effective heat transfer depth of the i-th borehole, in meters. This represents the specific heat at constant pressure of a fluid, expressed in J / (kg·K). This represents the flow rate of the mass / volume of the i-th borehole, in units of kg / s or m³ / s.

[0098] For each borehole, the total thermal resistance of the borehole The calculation is shown in equation (8):

[0099] (8)

[0100] The total thermal resistance characterizes the overall heat transfer resistance between the fluid and the outer soil layer. This represents the equivalent radius of the annular gap, in meters. It is the geometric average of the inner and outer radii of the annular gap and is used to calculate the heat transfer in the annular gap region. It represents the convective heat transfer coefficient of the fluid in the annulus, with units of W / (m²·K), and depends on the annulus flow rate, flow pattern, and fluid properties; It represents the equivalent thermal conductivity of the outer strata or cement ring and the soil, with units of W / (m·K); This indicates the outer tube radius, in meters (m). This indicates the borehole radius, in meters (m). To represent pi, we can take the value 3.1416.

[0101] Corrected unit step response function As shown in equation (9):

[0102] (9).

[0103] The total thermal resistance of the borehole described above is applicable to medium-deep coaxial geothermal wells under strong convection conditions. The convective thermal resistance of the inner tube and the conductive thermal resistance of the steel tube can be ignored. The total thermal resistance mainly consists of two parts: heat transfer through the annular fluid and heat conduction through the outer soil layer. The calculation is simple and highly accurate.

[0104] Figure 5 A schematic diagram illustrating the superposition of temperature fields generated by the combined influence of multiple boreholes on any soil point outside the boreholes according to an embodiment of the present invention is shown.

[0105] like Figure 5 As shown, the temperature change information corresponding to each of multiple boreholes, such as D1, D2, ..., Dn, can be superimposed using a three-dimensional function. This function represents the underground temperature generated by the combined influence of all boreholes on each soil point (x, y, z) at any given time t. It can be represented as a superposition form as shown in equations (10) to (11):

[0106] (10)

[0107] (11)

[0108] Indicates a historical moment; This represents the distance between any point (x, y, z) and the central axis of the i-th borehole; and Represents the x and y coordinates of the i-th borehole; This indicates that after applying a unit step heat load to the borehole wall of the i-th buried pipe heat exchanger, the heat transfer temperature will be significantly reduced. Duration, points (r) i The difference between the temperature of (z) and the initial temperature is the unit step response function, also known as the excess temperature. This indicates the location of the i-th borehole at a historical moment. The heat absorption and release power; Indicates the effective heat transfer depth; Indicates thermal diffusivity; for The simplified form of .

[0109] In equation (11) above, the first row represents the governing equation for heat transfer in soil and rock; the second and third rows represent the borehole wall boundary conditions, used to describe the coupled heat transfer process between the soil and the fluid inside the borehole; the fourth and fifth rows represent the far-field boundary conditions, assuming that the temperature gradient away from the borehole wall tends to zero; the sixth row represents the initial conditions, indicating that the temperature distribution is in a steady state during the initial stage of system operation. In determining... Then, the three-dimensional temperature field of the multi-hole system can be obtained by linear superposition of equations (10) to (11), so as to realize the rapid long-cycle simulation of the ground source heat pump system.

[0110] In the process of implementing the embodiments of the present invention, it was also found that, since the heat load change rate of the solar collector may fluctuate drastically, such as the alternation of day and night or weather changes, a fixed time step may fail to capture rapid temperature changes when the heat load changes drastically, resulting in insufficient calculation accuracy; while when the heat load changes slowly, redundant calculations increase time costs, resulting in low calculation efficiency, thereby affecting the efficiency and accuracy of the overall simulation process and making it difficult to adapt to the intermittent characteristics of solar energy input.

[0111] Therefore, in one embodiment of the present invention, the predetermined time step can be dynamically adjusted based on the rate of change of the heat load of the solar collector.

[0112] In one example, a method for dynamically adjusting the heat load change rate based on the collector may include: based on error control, at the end of each time step, evaluating the local truncation error generated by the current step, and adjusting the next time step according to the magnitude of the local truncation error so that the local truncation error remains within an acceptable range.

[0113] In another example, the method for dynamically adjusting the heat load change rate of the solar collector may include: obtaining a reference time step at the current time t based on the ratio of a preset parameter value used to control the sensitivity of the step size change to the heat load change rate of the solar collector at the current time t, wherein the heat load change rate of the solar collector at the current time t indicates the heat load change rate of the solar collector from time (t-Δt) to time (t+Δt); if it is determined that the reference time step at the current time t is less than a step size threshold, updating the reference time step at the current time t to a predetermined time step; if it is determined that the reference time step at the current time t is greater than or equal to the step size threshold, updating the step size threshold to the predetermined time step.

[0114] Preset parameter values ​​can include empirical constants or adjustable coefficients. For example, they can be calibrated using historical simulation data or experimental data to find the optimal value that balances accuracy and efficiency under specific system and operating conditions. Alternatively, they can be manually set according to simulation requirements: smaller values ​​for higher accuracy and larger values ​​for lower accuracy but higher efficiency.

[0115] A larger rate of change in heat load indicates a more unstable system state, requiring a smaller time step to capture its dynamic behavior. The rate of change in heat load can be obtained by numerical differentiation or difference calculation of the heat load data of the collector from time (t-Δt) to time (t+Δt).

[0116] The step size threshold can be understood as the preset maximum allowable time step size, which is used to limit the upper limit of the time step size to prevent the calculated reference time step size from being too large when the heat load changes very slowly, which may lead to some fast transient processes being ignored or the accumulated error being too large.

[0117] For example, the instantaneous heating power of a solar collector can be determined by solar irradiance and collection efficiency, as shown in equation (12):

[0118] (12)

[0119] This represents the instantaneous heating power at the current time t, in watts (W). This indicates the area of ​​the solar collector, in m². This represents the solar irradiance at the current time t, expressed in W / m². The heat collection efficiency can be understood as the proportion (dimensionless or percentage) of solar radiation energy received by the solar collector converted into usable heat energy per unit time, as shown in the following formula (13):

[0120] (13)

[0121] Optical efficiency, also known as zero-temperature efficiency, represents the highest efficiency that a solar collector can achieve under conditions of no heat loss when the temperature of the absorber plate is equal to the ambient temperature, reflecting its optical absorption performance. The primary heat loss coefficient, expressed in W / (m²·K), represents the heat loss effect that increases linearly with temperature difference. It is mainly caused by convection and some radiation losses, and its value can range from 3.5 to 6.0. This represents the secondary heat loss coefficient, with units of W / (m²·K²), used to describe nonlinear loss effects such as high-temperature radiation when the temperature difference is large, and its value can range from 0.005 to 0.02. This represents the difference between the average temperature of the solar collector's absorber plate or circulating fluid and the ambient air temperature, expressed in K or °C. This represents the solar irradiance of the solar collector at the current time t, expressed in W / m², and is a baseline input that affects efficiency calculations.

[0122] The predetermined time step Δt can be dynamically adjusted according to the rate of change of heat load, as shown in equation (14) below:

[0123] (14)

[0124] Where, Δt max This represents the maximum allowable step size, such as 1 hour; C represents an empirical constant, in units of W / m², which controls the sensitivity of step size changes. Indicates heat load The rate of change with time t, in units of W / m²·s, can be determined based on the instantaneous heating power mentioned above, if the two are equal; for the simulation duration, it can be discretized into t0, ..., t n t n+1 ,therefore, It can represent from t n to t n+1 The time step.

[0125] According to embodiments of the present invention, when the reference time step t at the current time is determined to be less than the step size threshold, it indicates that the heat load is changing drastically. Using this reference time step t at the current time as the actual simulation step size, i.e., the predetermined time step size, ensures simulation accuracy. Conversely, when the reference time step t at the current time is determined to be greater than or equal to the step size threshold, it indicates that the heat load is changing gradually. Using the step size threshold as the actual simulation step size improves computational efficiency and at least partially solves the problem of balancing computational efficiency and simulation accuracy in traditional methods.

[0126] Figure 6A block diagram of a simulation device for a solar ground source heat pump system according to an embodiment of the present invention is shown. The solar ground source heat pump system includes at least: a buried pipe heat exchanger and a collector, wherein the buried pipe heat exchanger is buried in the soil through at least one borehole, and the collector is located in the outdoor environment.

[0127] like Figure 6 As shown, the simulation device 600 for a solar ground source heat pump system includes a determination module 610 and an overlay module 620.

[0128] The determination module 610 is used for each borehole in at least one borehole to: determine the distance information of any soil point in a predetermined soil region outside the borehole wall from the borehole; based on the distance information, obtain the unit step response function corresponding to any soil point from a pre-built database, the database storing the mapping relationship between the location of the soil point and the unit step response function, the unit step response function indicating the temperature change caused by the borehole to the soil point at different durations under a unit step heat load; and calculate the historical step heat load, simulation duration, and unit step response function corresponding to any soil point of the buried pipe heat exchanger installed in the borehole to obtain the temperature change information caused by the borehole to any soil point within the simulation duration.

[0129] The overlay module 620 is used to overlay the temperature change information corresponding to each borehole in at least one borehole to obtain the total temperature change information of any soil point within the simulation time.

[0130] According to embodiments of this disclosure, any plurality of modules in determining module 610 and superimposed module 620 can be implemented in a single module, or any one of these modules can be split into multiple modules. Alternatively, at least a portion of the functionality of one or more of these modules can be combined with at least a portion of the functionality of other modules and implemented in a single module. According to embodiments of this disclosure, at least one of determining module 610 and superimposed module 620 can be at least partially implemented as hardware circuitry, such as a field-programmable gate array (FPGA), a programmable logic array (PLA), a system-on-a-chip, a system-on-a-substrate, a system-on-package, an application-specific integrated circuit (ASIC), or any other reasonable means of integrating or packaging circuitry, or implemented in software, hardware, or firmware, or in any suitable combination of any of these three implementation methods. Alternatively, at least one of determining module 610 and superimposed module 620 can be at least partially implemented as a computer program module, which, when run, can perform corresponding functions.

[0131] It should be noted that the simulation device part of the solar ground source heat pump system in the embodiments of the present invention corresponds to the simulation method part of the solar ground source heat pump system in the embodiments of the present invention. For a detailed description of the simulation device part of the solar ground source heat pump system, please refer to the simulation method part of the solar ground source heat pump system, which will not be repeated here.

[0132] Figure 7 A block diagram of an electronic device suitable for implementing a simulation method for a solar ground source heat pump system according to an embodiment of the present invention is shown.

[0133] like Figure 7 As shown, an electronic device 700 according to an embodiment of the present invention includes a processor 701, which can perform various appropriate actions and processes according to a program stored in a read-only memory ROM 702 or a program loaded from a storage portion 708 into a random access memory RAM 703. The processor 701 may include, for example, a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or an associated chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 701 may also include onboard memory for caching purposes. The processor 701 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of the present invention.

[0134] RAM 703 stores various programs and data required for the operation of electronic device 700. Processor 701, ROM 702, and RAM 703 are interconnected via bus 704. Processor 701 executes various operations of the method flow according to embodiments of the present invention by executing programs in ROM 702 and / or RAM 703. It should be noted that programs may also be stored in one or more memories other than ROM 702 and RAM 703. Processor 701 may also execute various operations of the method flow according to embodiments of the present invention by executing programs stored in one or more memories.

[0135] According to an embodiment of the present invention, the electronic device 700 may further include an input / output (I / O) interface 705, which is also connected to a bus 704. The electronic device 700 may also include one or more of the following components connected to the input / output (I / O) interface 705: an input section 706 including a keyboard, mouse, etc.; an output section 707 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 708 including a hard disk, etc.; and a communication section 709 including a network interface card such as a LAN card, modem, etc. The communication section 709 performs communication processing via a network such as the Internet. A drive 710 is also connected to the input / output (I / O) interface 705 as needed. A removable medium 711, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on the drive 710 as needed so that computer programs read from it can be installed into the storage section 708 as needed.

[0136] The present invention also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiments; or it may exist independently and not assembled into the device / apparatus / system. The computer-readable storage medium carries one or more programs, which, when executed, implement the method according to the embodiments of the present invention.

[0137] According to embodiments of the present invention, a computer-readable storage medium may be a non-volatile computer-readable storage medium, such as including, but not limited to: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. For example, according to embodiments of the present invention, a computer-readable storage medium may include ROM 702 and / or RAM 703 and / or one or more memories other than ROM 702 and RAM 703 described above.

[0138] Embodiments of the present invention also include a computer program product comprising a computer program containing program code for performing the methods shown in the flowchart. When the computer program product is run on a computer system, the program code is used to cause the computer system to implement the methods provided in the embodiments of the present invention.

[0139] When the computer program is executed by the processor 701, it performs the functions defined in the system / apparatus of this invention. According to embodiments of the invention, the systems, apparatuses, modules, units, etc., described above can be implemented by computer program modules.

[0140] In one embodiment, the computer program may rely on a tangible storage medium such as an optical storage device or a magnetic storage device. In another embodiment, the computer program may also be transmitted and distributed in the form of signals over a network medium, and may be downloaded and installed via the communication section 709, and / or installed from a removable medium 711. The program code contained in the computer program can be transmitted using any suitable network medium, including but not limited to: wireless, wired, etc., or any suitable combination thereof.

[0141] In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 709, and / or installed from the removable medium 711. When the computer program is executed by the processor 701, it performs the functions defined in the system of this embodiment of the invention. According to embodiments of the invention, the systems, devices, apparatuses, modules, units, etc., described above can be implemented by computer program modules.

[0142] According to embodiments of the present invention, program code for executing the computer programs provided in the embodiments of the present invention can be written in any combination of one or more programming languages. Specifically, these computational programs can be implemented using high-level procedural and / or object-oriented programming languages, and / or assembly / machine languages. Programming languages ​​include, but are not limited to, languages ​​such as Java, C++, Python, "C", or similar programming languages. The program code can be executed entirely on the user's computing device, partially on the user's device, partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0143] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram or flowchart, and combinations of blocks in a block diagram or flowchart, may be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0144] Those skilled in the art will understand that the features described in the various embodiments of the present invention can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments of the present invention can be combined and / or combined in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or combinations fall within the scope of the present invention.

[0145] The embodiments of the present invention have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

Claims

1. A simulation method for a solar ground source heat pump system, characterized in that, A solar ground source heat pump system includes at least: a buried pipe heat exchanger and a collector, wherein the buried pipe heat exchanger is buried in the soil through at least one borehole and the collector is installed in the outdoor environment. The simulation method includes: For each of the at least one boreholes: Determine the distance information of any soil point within a predetermined soil area outside the borehole wall from the borehole; Based on the distance information, a unit step response function corresponding to any soil point is obtained from a pre-built database. The database stores the mapping relationship between the location of the soil point and the unit step response function. The unit step response function indicates the temperature change caused by the borehole to the soil point at different times under a unit step thermal load. The historical step thermal load, simulation duration, and unit step response function corresponding to any soil point of the buried pipe heat exchanger installed in the borehole are calculated to obtain the temperature change information caused by the borehole to any soil point within the simulation duration. The temperature change information corresponding to each borehole in the at least one borehole is superimposed to obtain the total temperature change information of any soil point within the simulation time. The database is pre-built through the following steps: Based on the temperature, soil density, specific heat capacity, and thermal conductivity of any soil point in the predetermined soil region, a three-dimensional heat conduction equation is constructed. The predetermined soil region is divided into a cubic grid composed of grid points, and time is divided into predetermined time steps; Based on the cubic mesh composed of the grid points, the predetermined time step, and the three-dimensional heat conduction equation, a difference equation is constructed. Based on the initial temperature of the predetermined soil region, the outer boundary conditions of the predetermined soil region, the borehole wall boundary conditions of the target borehole, and the unit step heat load of the target borehole, the temperature distribution of the difference equation at different times is solved with the predetermined time step to obtain the temperature change of each grid point relative to the initial temperature at different times. The target borehole is located at the center point of the predetermined soil region. The position of each grid point is determined as the position of the soil point; The mapping relationship is determined based on the temperature change of each grid point relative to the initial temperature at different times and the location of the soil point, and stored in the database.

2. The simulation method according to claim 1, characterized in that, Before calculating the historical step thermal load of the buried pipe heat exchanger installed in the borehole, the simulation duration, and the unit step response function corresponding to any soil point, the following steps are also included: The baseline response function is obtained by using the ratio of the temperature change at any soil point to the unit step heat load in each of the at least one boreholes under actual operation. Based on the fluid parameters of each borehole in the at least one borehole under actual operating conditions, a measured response function is determined, wherein the fluid parameters include at least: the inlet temperature, outlet temperature, total thermal resistance, effective heat transfer depth, and initial ground temperature of the borehole. The residual function is obtained based on the difference between the measured response function and the reference response function; Based on the residual function, the unit step response function corresponding to any soil point is corrected.

3. The simulation method according to claim 2, characterized in that, The borehole includes an inner tube and an outer tube. The total thermal resistance indicates the heat transfer resistance between the fluid inside the borehole and the soil outside the borehole. The total thermal resistance is composed of the fluid convection thermal resistance and the external medium thermal conductivity thermal resistance connected in series.

4. The simulation method according to claim 1, characterized in that, The predetermined time step is dynamically adjusted based on the rate of change of the heat load of the solar collector.

5. The simulation method according to claim 4, characterized in that, The method for dynamically adjusting the heat load change rate based on the solar collector includes: Based on the ratio of the preset parameter value used to control the sensitivity of step size change to the heat load change rate of the collector at the current time t, the reference time step at the current time t is obtained, wherein the heat load change rate of the collector at the current time t indicates the heat load change rate of the collector from time (t-Δt) to time (t+Δt), and Δt represents the predetermined time step; If it is determined that the reference time step at the current time t is less than the step size threshold, the reference time step at the current time t is updated to the predetermined time step. If the reference time step at the current time t is determined to be greater than or equal to the step size threshold, the step size threshold is updated to the predetermined time step.

6. The simulation method according to claim 1, characterized in that, The plurality of cubic grids within the predetermined soil area are non-uniform grids, and the distance between the grid points and the target borehole is inversely proportional to the volume of the cubic grid.

7. The simulation method according to claim 1, characterized in that, When the outer boundary condition of the predetermined soil region indicates that the distance between the soil point and the borehole exceeds a distance threshold, the temperature change of the soil point relative to the initial temperature at different times is zero. The borehole wall boundary condition indicates that the heat flux density conducted from the interior of the borehole wall to the borehole wall is equal to the heat flux density carried away by the fluid inside the borehole from the borehole wall by convection.

8. A simulation device for a solar ground source heat pump system, characterized in that, A solar ground source heat pump system includes at least: a buried pipe heat exchanger and a collector, wherein the buried pipe heat exchanger is buried in the soil through at least one borehole and the collector is installed in the outdoor environment. The simulation device includes: A determining module is configured for each of the at least one boreholes: Determine the distance information of any soil point within a predetermined soil area outside the borehole wall from the borehole; Based on the distance information, a unit step response function corresponding to any soil point is obtained from a pre-built database. The database stores the mapping relationship between the location of the soil point and the unit step response function. The unit step response function indicates the temperature change caused by the borehole to the soil point at different times under a unit step thermal load. The historical step thermal load, simulation duration, and unit step response function corresponding to any soil point of the buried pipe heat exchanger installed in the borehole are calculated to obtain the temperature change information caused by the borehole to any soil point within the simulation duration. The overlay module is used to overlay the temperature change information corresponding to each borehole in the at least one borehole to obtain the total temperature change information of any soil point within the simulation time. The database is pre-built through the following steps: Based on the temperature, soil density, specific heat capacity, and thermal conductivity of any soil point in the predetermined soil region, a three-dimensional heat conduction equation is constructed. The predetermined soil region is divided into a cubic grid composed of grid points, and time is divided into predetermined time steps; Based on the cubic mesh composed of the grid points, the predetermined time step, and the three-dimensional heat conduction equation, a difference equation is constructed. Based on the initial temperature of the predetermined soil region, the outer boundary conditions of the predetermined soil region, the borehole wall boundary conditions of the target borehole, and the unit step heat load of the target borehole, the temperature distribution of the difference equation at different times is solved with the predetermined time step to obtain the temperature change of each grid point relative to the initial temperature at different times. The target borehole is located at the center point of the predetermined soil region. The position of each grid point is determined as the position of the soil point; The mapping relationship is determined based on the temperature change of each grid point relative to the initial temperature at different times and the location of the soil point, and stored in the database.

9. An electronic device, comprising: One or more processors; Memory, used to store one or more computer programs. The characteristic feature is that the one or more processors execute the one or more computer programs to implement the steps of the simulation method according to any one of claims 1 to 7.

10. A computer-readable storage medium having executable instructions stored thereon, characterized in that, When the instruction is executed by the processor, it causes the processor to implement the simulation method according to any one of claims 1 to 7.

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