A method and apparatus for co-simulation of an air conditioning system

Abstract

This application provides a co-simulation method and apparatus for an air conditioning system, relating to the field of automotive industry technology. The method includes: constructing a one-dimensional simulation model; inputting simulation operating condition parameters into the one-dimensional simulation model for simulation to obtain the predicted heat output of the condenser module; constructing a three-dimensional geometric model of the vehicle's front compartment, and importing the three-dimensional geometric model into three-dimensional fluid dynamics simulation software for region division and mesh generation to obtain a three-dimensional fluid dynamics simulation model; configuring boundary conditions in the three-dimensional fluid dynamics simulation model based on the simulation operating condition parameters and predicted heat output, and running the three-dimensional fluid dynamics simulation calculation until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry; using the inlet air velocity and inlet air temperature as boundary conditions, inputting them into the one-dimensional simulation model for co-simulation solution to obtain the performance evaluation parameters of the air conditioning system. Therefore, this application can improve the accuracy of the performance evaluation parameters of the air conditioning system.

Description

Technical Field

[0001] This application relates to the field of automotive industry technology, and in particular to a co-simulation method and apparatus for an air conditioning system. Background Technology

[0002] The performance of the air conditioning system in new energy vehicles is directly related to the comfort of the passenger compartment and the energy consumption of the whole vehicle. Therefore, it is necessary to conduct performance evaluation of the air conditioning system under different operating conditions (such as idling, low-speed driving, high-speed driving, etc.) in the early design stage.

[0003] Currently, one-dimensional simulation software or three-dimensional fluid dynamics (CFD) simulation software is typically used to evaluate the performance of air conditioning systems.

[0004] However, on the one hand, one-dimensional simulation cannot reflect the impact of the complex geometry of the vehicle's front compartment (such as grilles, bumpers, fans, etc.) on airflow obstruction and disturbance, leading to distortion of the performance evaluation parameters of the air conditioning system. On the other hand, although three-dimensional fluid dynamics simulation can accurately solve the flow field and temperature field of the vehicle's front compartment, it requires the heat output of the condenser module as a boundary condition. Currently, this heat output is usually estimated using a fixed value or a simplified heat load formula, which cannot reflect the dynamic changes of the air conditioning system under different operating conditions, also leading to distortion of the air conditioning system's performance evaluation parameters. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a co-simulation method and apparatus for air conditioning systems, which can improve the accuracy of performance evaluation parameters for air conditioning systems.

[0006] The embodiments of this application disclose the following technical solutions: In a first aspect, this application discloses a co-simulation method for an air conditioning system, the method comprising: A one-dimensional simulation model is constructed; the one-dimensional simulation model includes a one-dimensional model of the whole vehicle system and a one-dimensional model of the air conditioning system; the one-dimensional model of the air conditioning system includes a condenser module; The simulation operating parameters are input into the one-dimensional simulation model for simulation to obtain the predicted heat output of the condenser module. A three-dimensional geometric model of the vehicle's front compartment is constructed, and the three-dimensional geometric model is imported into a three-dimensional fluid dynamics simulation software for region division and mesh generation to obtain a three-dimensional fluid dynamics simulation model; the three-dimensional geometric model includes the geometry of the condenser; Based on the simulation operating parameters and the predicted heat generation, boundary conditions are configured in the three-dimensional fluid dynamics simulation model, and the three-dimensional fluid dynamics simulation calculation is run until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry. The intake air velocity and intake air temperature are used as boundary conditions and input into the one-dimensional simulation model for joint simulation solution to obtain the performance evaluation parameters of the air conditioning system.

[0007] Optionally, the simulation operating parameters include at least one of compressor speed, ambient temperature, blower air volume, and simulation duration.

[0008] Optionally, the performance evaluation parameters include at least one of the following: air outlet temperature, average passenger compartment temperature, battery temperature, battery inlet water temperature, and compressor high-pressure pressure.

[0009] Optionally, configuring boundary conditions in the three-dimensional fluid dynamics simulation model includes: Based on the simulation parameters, set the velocity inlet boundary conditions, pressure outlet boundary conditions, wall parameter boundary conditions, and cooling fan speed boundary conditions for the three-dimensional fluid dynamics simulation model. Furthermore, based on the wind resistance MAP table of the condenser geometry, the inertial resistance boundary conditions and viscous resistance boundary conditions of the condenser geometry in the three-dimensional fluid dynamics simulation model are set.

[0010] Optionally, the step of using the inlet air velocity and the inlet air temperature as boundary conditions and inputting them into the one-dimensional simulation model for joint simulation solution includes: If the fluctuation rates of the inlet air velocity and inlet air temperature of the condenser geometry are both less than the corresponding preset thresholds within N consecutive simulation iterations, then the inlet air velocity and the inlet air temperature are used as boundary conditions and input into the one-dimensional simulation model for joint simulation solution; N is a positive integer.

[0011] Secondly, this application discloses a co-simulation device for an air conditioning system, the device comprising: The first construction module is used to build a one-dimensional simulation model; the one-dimensional simulation model includes a one-dimensional model of the whole vehicle system and a one-dimensional model of the air conditioning system; the one-dimensional model of the air conditioning system includes a condenser module. The first simulation module is used to input the simulation operating condition parameters into the one-dimensional simulation model for simulation and to obtain the predicted heat output of the condenser module. The second construction module is used to build a three-dimensional geometric model of the vehicle's front compartment, and import the three-dimensional geometric model into three-dimensional fluid dynamics simulation software for region division and mesh generation to obtain a three-dimensional fluid dynamics simulation model; the three-dimensional geometric model includes the geometry of the condenser; The second simulation module is used to configure boundary conditions in the three-dimensional fluid dynamics simulation model according to the simulation operating parameters and the predicted heat generation, and run the three-dimensional fluid dynamics simulation calculation until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry. The third simulation module is used to input the intake air velocity and intake air temperature as boundary conditions into the one-dimensional simulation model for joint simulation and solution, so as to obtain the performance evaluation parameters of the air conditioning system.

[0012] Optionally, the simulation operating parameters include at least one of compressor speed, ambient temperature, blower air volume, and simulation duration.

[0013] Optionally, the performance evaluation parameters include at least one of the following: air outlet temperature, average passenger compartment temperature, battery temperature, battery inlet water temperature, and compressor high-pressure pressure.

[0014] Optionally, the second simulation module is specifically used to: set the velocity inlet boundary conditions, pressure outlet boundary conditions, wall parameter boundary conditions, and cooling fan speed boundary conditions of the three-dimensional fluid dynamics simulation model according to the simulation operating parameters; and set the inertial drag boundary conditions and viscous drag boundary conditions of the condenser geometry in the three-dimensional fluid dynamics simulation model according to the wind resistance MAP table of the condenser geometry.

[0015] Optionally, the third simulation module is specifically used to: if the fluctuation rate of the inlet air velocity and the inlet air temperature of the condenser geometry is less than the corresponding preset threshold within N consecutive simulation iteration steps, then the inlet air velocity and the inlet air temperature are used as boundary conditions and input into the one-dimensional simulation model for joint simulation solution; N is a positive integer.

[0016] Compared with the prior art, this application has the following beneficial effects: This application provides a co-simulation method and apparatus for an air conditioning system. The core of this application lies in the bidirectional coupling of one-dimensional and three-dimensional data: On one hand, by constructing a three-dimensional geometric model of the vehicle's front compartment (including the condenser geometry) and importing it into three-dimensional fluid dynamics simulation software for region division and mesh generation, this application can accurately simulate the obstruction and disturbance of airflow by components such as grilles, bumpers, and fans. This ensures that the intake air velocity and temperature output by the three-dimensional simulation are true values ​​considering the actual geometric structure and flow field distribution. These values ​​are then used as boundary conditions input into the one-dimensional simulation model, freeing the one-dimensional simulation from relying on simplified empirical assumptions. On the other hand, this application dynamically calculates the predicted heat generation of the condenser module under different simulation operating parameters using a one-dimensional simulation model (including a one-dimensional model of the vehicle system and a one-dimensional model of the air conditioning system, the one-dimensional model of the air conditioning system including the condenser module). This predicted heat generation reflects the dynamic response of the air conditioning system. Then, this predicted heat generation is used as a boundary condition input into the three-dimensional simulation model, enabling the three-dimensional fluid dynamics simulation to calculate the intake conditions under the correct heat load. Therefore, this application can improve the accuracy of the performance evaluation parameters of the air conditioning system. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart of a co-simulation method for an air conditioning system provided in this application embodiment; Figure 2 A schematic diagram illustrating a region division provided in an embodiment of this application; Figure 3 A schematic diagram of a mesh division provided for an embodiment of this application; Figure 4 This is a schematic diagram of a co-simulation device for an air conditioning system provided in an embodiment of this application. Detailed Implementation

[0019] As described earlier, on the one hand, one-dimensional simulation cannot reflect the impact of the complex geometry of the vehicle's front compartment (such as grilles, bumpers, and fans) on airflow obstruction and disturbance, leading to distortion of the air conditioning system's performance evaluation parameters. On the other hand, while three-dimensional fluid dynamics simulation can accurately solve the flow and temperature fields of the vehicle's front compartment, it requires the heat generated by the condenser module as a boundary condition. Currently, this heat generation is usually estimated using a fixed value or a simplified heat load formula, which cannot reflect the dynamic changes of the air conditioning system under different operating conditions, also leading to distortion of the air conditioning system's performance evaluation parameters.

[0020] The inventors, through research, have proposed a co-simulation method and apparatus for air conditioning systems. The core of this application lies in the bidirectional coupling of one-dimensional and three-dimensional data: On one hand, by constructing a three-dimensional geometric model of the vehicle's front compartment (including the condenser geometry) and importing it into three-dimensional fluid dynamics simulation software for region division and mesh generation, this application can accurately simulate the obstruction and disturbance of airflow by components such as grilles, bumpers, and fans. This ensures that the intake air velocity and temperature output by the three-dimensional simulation are true values ​​considering the actual geometric structure and flow field distribution. These values ​​are then used as boundary conditions input into the one-dimensional simulation model, freeing the one-dimensional simulation from reliance on simplified empirical assumptions. On the other hand, this application dynamically calculates the predicted heat generation of the condenser module under different simulation operating parameters using a one-dimensional simulation model (including a one-dimensional model of the entire vehicle system and a one-dimensional model of the air conditioning system, the one-dimensional model of the air conditioning system including the condenser module). This predicted heat generation reflects the dynamic response of the air conditioning system. Then, this predicted heat generation is input as a boundary condition into the three-dimensional simulation model, enabling the three-dimensional fluid dynamics simulation to calculate intake conditions under the correct heat load. Therefore, this application can improve the accuracy of performance evaluation parameters for air conditioning systems.

[0021] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0022] See Figure 1 The figure is a flowchart of a co-simulation method for an air conditioning system provided in an embodiment of this application. The method includes: S101: Build a one-dimensional simulation model; the one-dimensional simulation model includes a one-dimensional model of the whole vehicle system and a one-dimensional model of the air conditioning system; the one-dimensional model of the air conditioning system includes the condenser module.

[0023] The one-dimensional simulation model includes a one-dimensional model of the whole vehicle system and a one-dimensional model of the air conditioning system. The one-dimensional model of the air conditioning system includes the condenser module.

[0024] It should be noted that in the one-dimensional simulation model, the boundary conditions required for the condenser module include at least the inlet air velocity and inlet air temperature. In traditional one-dimensional simulations, the inlet air velocity and inlet air temperature are usually simplified to a static ambient temperature (e.g., uniformly set to 38°C) and a fixed air velocity. However, in this application, the inlet air velocity and inlet air temperature are provided in real time through subsequent three-dimensional fluid dynamics simulations.

[0025] The one-dimensional model of the entire vehicle system includes an evaporator module, a compressor module, a battery pack cooling module, an expansion valve module, a battery module, a battery water pump module, a blower module, and a passenger compartment module. These modules are coupled together in a one-dimensional simulation platform (such as AMESim or GT-SUITE).

[0026] It should be noted that in the one-dimensional simulation model, each physical component (such as heat exchanger, compressor, water pump, expansion valve, etc.) does not include specific geometric three-dimensional shape features, but rather its input and output characteristics are characterized entirely by empirical formulas, semi-empirical models, or MAP data tables extracted from bench tests.

[0027] S102: Input the simulation operating parameters into the one-dimensional simulation model for simulation to obtain the predicted heat output of the condenser module.

[0028] The simulation operating parameters include at least one of the following: compressor speed, ambient temperature, blower air volume, and simulation duration. See Table 1, which is a schematic table of simulation operating parameters provided in an embodiment of this application.

[0029] Table 1

[0030] It should be noted that the predicted heat output of the condenser module is positively correlated with compressor speed, ambient temperature, and blower airflow. When the compressor speed increases (e.g., from 4000 rpm to 6000 rpm), the refrigerant mass flow rate pumped per unit time increases significantly. Because more refrigerant participates in the cycle, the overall heat transfer capacity of the system increases; simultaneously, higher speed means increased work done by the compressor on the gas, leading to a significant increase in the refrigerant discharge enthalpy. This increased compressor power consumption is ultimately converted into heat energy, superimposed on the cooling capacity, resulting in a substantial increase in the total heat that the condenser module needs to dissipate (predicted heat output). When the ambient temperature increases (e.g., from 25°C to 38°C), the heat transfer temperature difference between the condenser surface and the ambient air is drastically reduced. To maintain heat dissipation, the refrigeration system must spontaneously increase the condensing pressure (condensing temperature) to rebuild a sufficient heat dissipation temperature difference. The increase in condensing pressure directly leads to increased compressor discharge resistance and pressure ratio, resulting in a sharp increase in compressor power consumption. Because the system requires more electrical energy to overcome the heat dissipation resistance caused by the high-temperature environment, this increased power consumption is again converted into heat, causing the predicted heat output of the condenser to increase with the rise in ambient temperature. When the blower airflow increases, it means that more hot air flows over the evaporator surface, making the heat exchange between the air side and the refrigerant side more intense, and the evaporator absorbs more heat from the passenger compartment (i.e., cooling capacity). The increase in heat absorption by the evaporator leads to changes in return gas temperature and pressure, requiring the compressor to remove more heat from the lower layers and do more work to maintain the cycle. Therefore, the increased load on the "heat absorption side" inevitably requires matching on the "heat release side," resulting in a corresponding increase in the predicted heat output of the condenser module.

[0031] S103: Build a three-dimensional geometric model of the vehicle's front compartment, and import the three-dimensional geometric model into a three-dimensional fluid dynamics simulation software for region division and mesh generation to obtain a three-dimensional fluid dynamics simulation model; the three-dimensional geometric model includes the geometry of the condenser.

[0032] First, a 3D geometric model of the vehicle's front compartment is created using 3D modeling software (such as UG, CATIA, or SolidWorks). It's important to note that to ensure high simulation accuracy, the 3D geometric model of the vehicle's front compartment must include all key components that significantly affect aerodynamics and heat transfer, including: condenser geometry, air conditioning fan geometry, motor geometry, and water pipe geometry. Furthermore, to reproduce the most realistic airflow entry path, the 3D geometric model of the vehicle's front compartment can also include components that significantly obstruct or disturb airflow, such as the front air intake grille (which determines the opening ratio and intake volume of the incoming cold air), the front bumper (causing airflow separation and reattachment), the subframe, crash beams, radiator brackets, and large high and low voltage wiring harnesses.

[0033] Next, the constructed 3D geometric model is imported into 3D CFD simulation software (such as STAR-CCM+ or Fluent). After importation, the region is divided. See [link / reference] Figure 2 This figure is a schematic diagram of a region partitioning method provided in an embodiment of this application. The essence of region partitioning is to divide the entire computational domain into several sub-regions based on the function, physical properties, and flow characteristics of different components within the vehicle's front compartment. The purpose of region partitioning is to set different mesh parameters and physical models for different regions. After region partitioning is completed, a computational mesh is generated for each sub-region (i.e., mesh generation) to obtain a three-dimensional fluid dynamics simulation model. See also... Figure 3 This figure is a schematic diagram of a mesh generation method provided in an embodiment of this application. The mesh generation can employ tetrahedral, trimmed hexahedral, or polyhedral meshes. It should be noted that this application can employ a localized meshing strategy: in critical areas with extreme flow field gradient changes and complex physical phenomena (such as the windward and leeward sides of the condenser, fan blade tips, and narrow intake grille gaps), smaller meshes are used to accurately capture fine flow field features such as airflow acceleration, separation vortices, and temperature wakes. Conversely, in areas far from the vehicle (such as the open areas in front of and above the wind tunnel), larger meshes are used, thus achieving a perfect balance between extremely high resolution and limited computing power.

[0034] S104: Based on the simulation operating parameters and predicted heat generation, configure boundary conditions in the three-dimensional fluid dynamics simulation model, and run the three-dimensional fluid dynamics simulation calculation until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry.

[0035] First, boundary conditions are set in the 3D fluid dynamics simulation software, including: setting the velocity inlet boundary conditions, pressure outlet boundary conditions, wall parameter boundary conditions, and cooling fan speed boundary conditions of the 3D fluid dynamics simulation model according to the simulation operating parameters; and setting the inertial drag boundary conditions and viscous drag boundary conditions of the condenser geometry in the 3D fluid dynamics simulation model according to the condenser geometry drag MAP table (the drag MAP table is usually obtained from bench experiments or detailed 3D simulations, which gives the pressure loss before and after the condenser under different oncoming wind speeds).

[0036] After setting the boundary conditions, run the 3D fluid dynamics simulation until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry. These inlet air velocity and inlet air temperature are the results obtained after the 3D simulation takes into account all geometric details such as the front compartment grille, fan, motor, and fan rotation effect.

[0037] S105: Input the intake air velocity and intake air temperature as boundary conditions into the one-dimensional simulation model for joint simulation and solution to obtain the performance evaluation parameters of the air conditioning system.

[0038] Because three-dimensional fluid dynamics calculation is a highly nonlinear iterative process, the airflow inside the front compartment will experience strong vortex shedding, flow separation, and transient oscillations (such as the Karman vortex street effect) when encountering complex geometry, causing drastic fluctuations in wind speed and temperature on the condenser surface in the early stages of the calculation. Therefore, to ensure the stability and reliability of the co-simulation, this application also introduces convergence criteria: If, within N consecutive simulation iterations, the fluctuation rates of the inlet air velocity and inlet air temperature of the condenser geometry are both less than the corresponding preset thresholds, then the inlet air velocity and inlet air temperature are used as boundary conditions and input into the one-dimensional simulation model for co-simulation. Here, N is a positive integer, typically chosen to balance computational efficiency and stability, ranging from 50 to 200 steps. The air velocity fluctuation threshold can be set to 1% to 5%, and the temperature fluctuation threshold can be set to 0.1℃ to 0.5℃. This mechanism completely eliminates the risk of numerical divergence in the co-simulation process, ensuring the absolute reliability of the entire multiphysics coupled simulation.

[0039] Performance evaluation parameters include at least one of the following: outlet air temperature, average passenger compartment temperature, battery temperature, battery inlet water temperature, and compressor high-pressure pressure. See Table 2, which is a schematic table of performance evaluation parameters provided in an embodiment of this application.

[0040] Table 2

[0041] It should be noted that the above performance evaluation parameters provide engineers with extremely valuable guidance: Firstly, the industry standard typically requires that the outlet temperature of the air conditioner under maximum cooling conditions should be ≤12℃. As shown in Table 2, under the "high-speed driving" condition, due to the extremely high vehicle speed, the oncoming wind brings a huge flow of cold air, resulting in excellent condenser heat dissipation. Therefore, the outlet temperature is the lowest (10℃), and the cooling effect on the passenger compartment is the best. However, under the "idling" condition, since the oncoming wind is completely lost, relying solely on fan suction, and hot air recirculation is very likely to occur in the engine compartment, the condenser inlet temperature is higher, and the outlet temperature rises to 12.5℃. Through this refined simulation, engineers can accurately determine whether the air conditioner's cooling capacity meets the design goals under the worst conditions, thereby guiding the selection of the evaporator or blower. Secondly, if the high pressure is too high, it will cause a sharp increase in compressor power consumption and may even lead to pipe rupture (the safety limit is usually ≤20 barA). Table 2 shows that the highest high-pressure condition, reaching 16.5 barA, occurs under idling conditions. This is because the poorest heat dissipation conditions force the condensing pressure to rise. The high-pressure data obtained from this co-simulation can help engineers accurately calibrate the compressor's maximum speed limit and the electric fan's start-stop control strategy, preventing the system from shutting down due to overpressure under extreme exposure conditions. Thirdly, for pure electric vehicles, the safe operating temperature range for batteries is typically between 25℃ and 35℃. "Battery temperature" and "battery inlet water temperature" directly reflect the heat exchange efficiency of the battery cooling module. Table 2 shows that the system can control the battery temperature within the safe range of 33℃ to 35℃ under different operating conditions (with the inlet water temperature maintained between 18℃ and 22℃). This indicates that in the vehicle's multi-thermal management loop (competing for cooling between the passenger compartment and the battery), one-dimensional and three-dimensional co-simulation can accurately predict the rationality of flow distribution, proving that the current electric water pump speed and expansion valve opening strategies are highly effective.

[0042] In summary, this application provides a co-simulation method for an air conditioning system. The core of this application lies in the bidirectional coupling of one-dimensional and three-dimensional data: On one hand, by constructing a three-dimensional geometric model of the vehicle's front compartment (including the condenser geometry) and importing it into three-dimensional fluid dynamics simulation software for region division and mesh generation, this method can accurately simulate the obstruction and disturbance of airflow by components such as grilles, bumpers, and fans. This ensures that the intake air velocity and temperature output by the three-dimensional simulation are true values ​​considering the actual geometric structure and flow field distribution. These values ​​are then used as boundary conditions input into the one-dimensional simulation model, freeing the one-dimensional simulation from relying on simplified empirical assumptions. On the other hand, this application dynamically calculates the predicted heat generation of the condenser module under different simulation operating parameters using a one-dimensional simulation model (including a one-dimensional model of the vehicle system and a one-dimensional model of the air conditioning system, the one-dimensional model of the air conditioning system including the condenser module). This predicted heat generation reflects the dynamic response of the air conditioning system. Then, this predicted heat generation is used as a boundary condition input into the three-dimensional simulation model, enabling the three-dimensional fluid dynamics simulation to calculate the intake conditions under the correct heat load. Therefore, this application can improve the accuracy of the performance evaluation parameters of the air conditioning system.

[0043] See Figure 4 The figure is a schematic diagram of a co-simulation device for an air conditioning system provided in an embodiment of this application. The co-simulation device 400 for the air conditioning system includes: The first construction module 401 is used to build a one-dimensional simulation model; the one-dimensional simulation model includes a one-dimensional model of the whole vehicle system and a one-dimensional model of the air conditioning system; the one-dimensional model of the air conditioning system includes a condenser module. The first simulation module 402 is used to input simulation operating condition parameters into a one-dimensional simulation model for simulation and to obtain the predicted heat output of the condenser module. The second construction module 403 is used to build a three-dimensional geometric model of the front compartment of the vehicle, and import the three-dimensional geometric model into three-dimensional fluid dynamics simulation software for region division and mesh generation to obtain a three-dimensional fluid dynamics simulation model; the three-dimensional geometric model includes the geometry of the condenser; The second simulation module 404 is used to configure boundary conditions in the three-dimensional fluid dynamics simulation model according to the simulation operating parameters and predicted heat generation, and run the three-dimensional fluid dynamics simulation calculation until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry. The third simulation module 405 is used to input the intake air velocity and intake air temperature as boundary conditions into the one-dimensional simulation model for joint simulation and solution, so as to obtain the performance evaluation parameters of the air conditioning system.

[0044] In one specific implementation, the simulation operating parameters include at least one of the following: compressor speed, ambient temperature, blower air volume, and simulation duration.

[0045] In one specific implementation, the performance evaluation parameters include at least one of the following: outlet temperature, average passenger compartment temperature, battery temperature, battery inlet water temperature, and compressor high-pressure pressure.

[0046] In one specific implementation, the second simulation module 404 is specifically used to: set the velocity inlet boundary conditions, pressure outlet boundary conditions, wall parameter boundary conditions, and cooling fan speed boundary conditions of the three-dimensional fluid dynamics simulation model according to the simulation operating parameters; and set the inertial resistance boundary conditions and viscous resistance boundary conditions of the condenser geometry in the three-dimensional fluid dynamics simulation model according to the condenser geometry wind resistance MAP table.

[0047] In one specific implementation, the third simulation module 405 is specifically used to: if the fluctuation rate of the inlet air velocity and the inlet air temperature of the condenser geometry is less than the corresponding preset threshold within N consecutive simulation iteration steps, then the inlet air velocity and the inlet air temperature are used as boundary conditions and input into the one-dimensional simulation model for joint simulation solution; N is a positive integer.

[0048] In summary, this application provides a co-simulation device for an air conditioning system. The core of this application lies in the bidirectional coupling of one-dimensional and three-dimensional data: On one hand, by constructing a three-dimensional geometric model of the vehicle's front compartment (including the condenser geometry) and importing it into three-dimensional fluid dynamics simulation software for region division and mesh generation, this application can accurately simulate the obstruction and disturbance of airflow by components such as grilles, bumpers, and fans. This ensures that the intake air velocity and temperature output by the three-dimensional simulation are true values ​​considering the actual geometric structure and flow field distribution. These values ​​are then used as boundary conditions input into the one-dimensional simulation model, freeing the one-dimensional simulation from relying on simplified empirical assumptions. On the other hand, this application dynamically calculates the predicted heat generation of the condenser module under different simulation operating parameters using a one-dimensional simulation model (including a one-dimensional model of the vehicle system and a one-dimensional model of the air conditioning system, the one-dimensional model of the air conditioning system including the condenser module). This predicted heat generation reflects the dynamic response of the air conditioning system. Then, this predicted heat generation is used as a boundary condition input into the three-dimensional simulation model, enabling the three-dimensional fluid dynamics simulation to calculate the intake conditions under the correct heat load. Therefore, this application can improve the accuracy of the performance evaluation parameters of the air conditioning system.

[0049] It should be noted that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for the device and system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method embodiments. The device and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components indicated as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of the solution in this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0050] The above description is merely one specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A co-simulation method for an air conditioning system, characterized in that, The method includes: A one-dimensional simulation model is constructed; the one-dimensional simulation model includes a one-dimensional model of the whole vehicle system and a one-dimensional model of the air conditioning system; the one-dimensional model of the air conditioning system includes a condenser module; The simulation operating parameters are input into the one-dimensional simulation model for simulation to obtain the predicted heat output of the condenser module. A three-dimensional geometric model of the vehicle's front compartment is constructed, and the three-dimensional geometric model is imported into a three-dimensional fluid dynamics simulation software for region division and mesh generation to obtain a three-dimensional fluid dynamics simulation model; the three-dimensional geometric model includes the geometry of the condenser; Based on the simulation operating parameters and the predicted heat generation, boundary conditions are configured in the three-dimensional fluid dynamics simulation model, and the three-dimensional fluid dynamics simulation calculation is run until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry. The intake air velocity and intake air temperature are used as boundary conditions and input into the one-dimensional simulation model for joint simulation solution to obtain the performance evaluation parameters of the air conditioning system.

2. The method according to claim 1, characterized in that, The simulation operating parameters include at least one of the following: compressor speed, ambient temperature, blower air volume, and simulation duration.

3. The method according to claim 1, characterized in that, The performance evaluation parameters include at least one of the following: air outlet temperature, average passenger compartment temperature, battery temperature, battery inlet water temperature, and compressor high-pressure.

4. The method according to claim 1, characterized in that, The configuration of boundary conditions in the three-dimensional fluid dynamics simulation model includes: Based on the simulation parameters, set the velocity inlet boundary conditions, pressure outlet boundary conditions, wall parameter boundary conditions, and cooling fan speed boundary conditions for the three-dimensional fluid dynamics simulation model. Furthermore, based on the wind resistance MAP table of the condenser geometry, the inertial resistance boundary conditions and viscous resistance boundary conditions of the condenser geometry in the three-dimensional fluid dynamics simulation model are set.

5. The method according to claim 1, characterized in that, The step of using the inlet air velocity and the inlet air temperature as boundary conditions and inputting them into the one-dimensional simulation model for joint simulation solution includes: If the fluctuation rates of the inlet air velocity and inlet air temperature of the condenser geometry are both less than the corresponding preset thresholds within N consecutive simulation iterations, then the inlet air velocity and the inlet air temperature are used as boundary conditions and input into the one-dimensional simulation model for joint simulation solution; N is a positive integer.

6. A co-simulation device for an air conditioning system, characterized in that, The device includes: The first construction module is used to build a one-dimensional simulation model; the one-dimensional simulation model includes a one-dimensional model of the whole vehicle system and a one-dimensional model of the air conditioning system; the one-dimensional model of the air conditioning system includes a condenser module. The first simulation module is used to input the simulation operating condition parameters into the one-dimensional simulation model for simulation and to obtain the predicted heat output of the condenser module. The second construction module is used to build a three-dimensional geometric model of the vehicle's front compartment, and import the three-dimensional geometric model into three-dimensional fluid dynamics simulation software for region division and mesh generation to obtain a three-dimensional fluid dynamics simulation model; the three-dimensional geometric model includes the geometry of the condenser; The second simulation module is used to configure boundary conditions in the three-dimensional fluid dynamics simulation model according to the simulation operating parameters and the predicted heat generation, and run the three-dimensional fluid dynamics simulation calculation until convergence to obtain the inlet air velocity and inlet air temperature of the condenser geometry. The third simulation module is used to input the intake air velocity and intake air temperature as boundary conditions into the one-dimensional simulation model for joint simulation and solution, so as to obtain the performance evaluation parameters of the air conditioning system.

7. The apparatus according to claim 6, characterized in that, The simulation operating parameters include at least one of the following: compressor speed, ambient temperature, blower air volume, and simulation duration.

8. The apparatus according to claim 6, characterized in that, The performance evaluation parameters include at least one of the following: air outlet temperature, average passenger compartment temperature, battery temperature, battery inlet water temperature, and compressor high-pressure.

9. The apparatus according to claim 6, characterized in that, The second simulation module is specifically used to: set the velocity inlet boundary conditions, pressure outlet boundary conditions, wall parameter boundary conditions, and cooling fan speed boundary conditions of the three-dimensional fluid dynamics simulation model according to the simulation operating parameters; and set the inertial drag boundary conditions and viscous drag boundary conditions of the condenser geometry in the three-dimensional fluid dynamics simulation model according to the wind resistance MAP table of the condenser geometry.

10. The apparatus according to claim 6, characterized in that, The third simulation module is specifically used to: if the fluctuation rate of the inlet air velocity and the inlet air temperature of the condenser geometry is less than the corresponding preset threshold within N consecutive simulation iteration steps, then the inlet air velocity and the inlet air temperature are used as boundary conditions and input into the one-dimensional simulation model for joint simulation solution; N is a positive integer.

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