Commercial vehicle thermal management simulation analysis method and device

Abstract

The invention belongs to the technical field of automobile thermal management simulation, and particularly relates to a commercial vehicle thermal management simulation analysis method and device, and the method comprises the following steps: constructing a power transmission system sub-model; constructing a cooling system sub-model; building a cabin system sub-model; constructing a radiator heat exchange sub-model; performing model correction on the constructed power transmission system sub-model, the cooling system sub-model, the cabin system sub-model and the radiator heat exchange sub-model, and then constructing a multi-system integrated heat management simulation model; and defining simulation parameters in the thermal management simulation model to perform simulation calculation analysis, and outputting an analysis result. In the early stage of research and development, the reliability of the thermal management system of the whole vehicle is calculated, and the temperature and pressure of an engine and flow distribution of cooling liquid of all branches are accurately predicted. And the thermal management system component model selection can be further realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of automobile thermal management simulation, and in particular relates to a method and device for simulation analysis of thermal management of a commercial vehicle. Background Art

[0002] The rapid development of the automobile industry has brought convenience to people's lives, but it has also brought increasingly severe social problems such as energy consumption. Energy conservation and emission reduction have become the development trend of automobile technology. Vehicle thermal management technology is an effective solution to achieve automobile energy conservation and emission reduction, and it has been favored by more and more institutions with its low cost advantage. Vehicle thermal management technology generally uses road or rotary tests to verify the solution. However, this verification method requires a lot of money and time investment, which increases the development cost. At present, more and more institutions use thermal management simulation technology for rapid verification in the early stage of development.

[0003] Existing vehicle thermal management simulations generally do not consider the mutual influence between the thermal management system and the powertrain system. On the one hand, the influence of the powertrain matching and performance optimization of the powertrain system on the thermal management system cannot be directly reflected; on the other hand, the energy-saving effect of the thermal management system cannot be more comprehensively evaluated through the fuel consumption of the vehicle.

[0004] Although thermal management simulation technology provides a fast verification method, it still needs to be improved to consider the interaction between the thermal management system and the powertrain system, so as to more comprehensively evaluate the effect of the thermal management system. Summary of the invention

[0005] In view of the above-mentioned problems existing in the existing whole vehicle thermal management simulation, the present invention provides a whole vehicle thermal management simulation analysis method and device for a commercial vehicle.

[0006] In a first aspect, the technical solution of the present invention provides a commercial vehicle thermal management simulation analysis method, comprising the following steps: Construct the powertrain sub-model; Construct cooling system sub-model; Construct the cabin system sub-model; Construct the heat transfer sub-model of the radiator; After model corrections are made to the constructed powertrain sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model, a multi-system integrated thermal management simulation model is constructed; Define simulation parameters in the thermal management simulation model to perform simulation calculation analysis and output analysis results. Define simulation parameters such as operating conditions and ambient temperature in the multi-system integrated thermal management simulation model. Set up post-processing result analysis in the simulation software, including vehicle speed, gearbox gear, 100L / Km fuel consumption, engine speed, engine torque, water pump flow, radiator flow, oil cooler flow, turbocharger flow, fan speed, fan power consumption, water pump power consumption, engine water outlet temperature, etc. Whether the analysis results meet the thermal management and economy-related evaluation requirements, if the results do not meet the requirements, relevant design and control strategy optimization can be carried out, and the multi-system integrated simulation platform can quickly iterate and verify the optimization plan.

[0007] As a preferred embodiment of the technical solution of the present invention, the step of constructing a power transmission system sub-model includes: Drag the powertrain module from the model library and drop it into the simulation window; Place each module according to the vehicle layout, make mechanical connections between the modules, and then connect the data lines according to the input and output signals; define the structure and performance parameters of each model to generate a powertrain simulation model Define simulation conditions, conduct vehicle economy simulation, compare simulation results with test data, adjust the constructed powertrain simulation model to complete the construction of the powertrain sub-model.

[0008] Construct a powertrain submodel in the AVL CruiseM software. Drag and drop the engine, clutch, gearbox, drive axle, half shaft, tire, vehicle, driver and cockpit modules from the model library to the model window in turn. Then place each module according to the layout of the vehicle, make mechanical connections between the modules, and then connect the data lines according to the input and output signals. At the same time, define the structure and performance parameters of each model. Finally, define the simulation conditions and perform vehicle economy simulation. By comparing the simulation results of vehicle speed, engine speed and torque, gearbox gear, vehicle fuel consumption and other simulation results with the test data, the calculation accuracy of the constructed powertrain simulation model can meet the requirements. The powertrain system can perform vehicle economy simulation alone; at the same time, it can be coupled with the cooling and cabin systems to develop a multi-system integrated thermal management simulation platform.

[0009] As a preferred embodiment of the technical solution of the present invention, the step of constructing a cooling system sub-model includes: According to the components involved in the vehicle cooling system, relevant component models are established in the simulation software; the relevant components include the engine, water pump, thermostat, oil cooler, turbocharger, radiator, expansion tank, etc.

[0010] Establish a pipeline model in the simulation software based on the connection relationship of actual components; According to the actual pipeline direction and coolant flow direction, the component models are connected through the pipeline model to build a cooling system simulation model; Define component simulation parameters; the component simulation parameters include: the size of the connecting pipeline, the speed-flow-head map and speed-flow-efficiency map of the water pump, the temperature rise and fall curve of the thermostat, and the large and small circulation flow resistance characteristics.

[0011] A component flow resistance model is established in the simulation software, and the flow coefficient is calibrated to ensure that the error accuracy of the flow resistance characteristics of the established component model and the test data is within 5%. The components include an engine, an oil cooler, an air compressor, a turbocharger, and a hot side radiator. The flow resistance characteristic is the pressure loss of the component at different flow rates, and the hot side radiator is an internal model of a radiator whose medium is coolant. The calibrated flow resistance component model is replaced in the cooling system model.

[0012] Input the preset working conditions and boundary parameters into the cooling system simulation model and solve it to obtain the simulation results; Based on the simulation results, the flow rate and flow resistance of each branch of the component are calibrated to complete the construction of the cooling system submodel. Input the preset working conditions and boundary parameters of the cooling system simulation model and solve them, including: engine speed and torque, ambient temperature, initial pressure, initial temperature of coolant, etc. Calibrate the flow rate and flow resistance of each branch of the engine, radiator, etc. through the cooling system simulation results. Make the calculation accuracy of the constructed cooling system simulation model meet the requirements. The cooling system submodel can perform cooling system flow and pressure simulation calculations independently. At the same time, it can be coupled with the power transmission and cabin systems to develop a multi-system integrated thermal management simulation platform.

[0013] As a preferred embodiment of the technical solution of the present invention, the step of constructing the cabin system sub-model includes: According to the layout structure of the relevant components of the cooling module in the engine compartment, a one-dimensional model of the compartment is established; In the simulation software, drag and drop the inlet pressure boundary, condenser, intercooler, cold side radiator, fan, and outlet pressure boundary modules to the model window and connect the modules according to the actual layout, and define the input and output signal connections; Establish a component flow resistance model in the simulation software and calibrate the friction coefficient of the flow resistance component; establish a component flow resistance model in the simulation software and calibrate the flow coefficient to ensure that the error accuracy of the flow resistance characteristics of the established component model and the test data is within 5%. The components include a condenser, an intercooler and a cold side radiator. The cold side radiator is an external model of a radiator with air as the medium.

[0014] According to the radiator air volume results calculated by the three-dimensional CFD cabin flow field, the oncoming air volume of the radiator in the model is calibrated; the construction of the cabin system submodel is completed. Ensure that the error of the radiator air volume calculated by the one-dimensional and three-dimensional simulation is within an acceptable range. The cabin system can calculate the cabin system air volume and pressure independently, and can be coupled with the powertrain system and cooling system to develop a multi-system integrated thermal management simulation platform.

[0015] As a preferred embodiment of the technical solution of the present invention, the step of calibrating the headwind volume of the radiator in the model according to the radiator volume result calculated by the three-dimensional CFD cabin flow field includes: Define the vehicle speed-fan speed-radiator air volume map module and time-vehicle speed map in the simulation software; Set the P and I parameters and the maximum and minimum values ​​of the PID module; Connect the actual value port of the PID module to the one-dimensional simulated air volume value of the radiator, and connect the demand value to the air volume value of the radiator simulated by three-dimensional CFD; Set the comparison results of the one-dimensional simulated air volume value and the three-dimensional CFD simulated air volume value. If the error is not within the set range, adjust the P and I values ​​of the PID for recalibration.

[0016] As a preferred embodiment of the technical solution of the present invention, the steps of constructing a heat exchange sub-model of the radiator include: Drag and drop the radiator cold side module, radiator hot side module, heat exchange unit, radiator cold and hot side friction coefficient map and inlet and outlet boundaries to the simulation window; Input the radiator heat dissipation performance data into the heat exchange unit, including the cold side inlet temperature and air volume, the hot side inlet temperature and coolant flow, and the radiator heat exchange capacity; Define the flow boundary at the cold side inlet of the radiator, define the pressure boundary at the outlet, define the inlet and outlet pressure boundaries at the hot side of the radiator, and calibrate the heat transfer performance of the radiator by correcting the heat transfer coefficient of the heat exchange unit; among them, the heat transfer sub-model of the radiator is modeled on both the cold and hot sides through the heat exchange unit, the cold side model is connected to the cold side boundary with which it exchanges heat, and the hot side model is connected to the hot side boundary with which it exchanges heat. Establish a radiator heat transfer model in the simulation software, calibrate the heat transfer coefficient of the built radiator heat transfer model, and ensure that the heat transfer characteristics of the built radiator model and the error accuracy of the experimental data are within 5%.

[0017] As a preferred embodiment of the technical solution of the present invention, the steps of constructing a multi-system integrated thermal management simulation model after model correction of the constructed power transmission system sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model include: The cabin system submodel is modified, and the modified cabin system submodel is integrated with the cooling system submodel through the radiator heat exchange submodel; Modify the cooling system submodel, and integrate the modified cooling system submodel with the powertrain submodel through the engine heat exchange MAP; The vehicle speed signal in the powertrain submodel is input to the vehicle speed input signal port of the inlet pressure boundary of the cabin system submodel to complete the integration of the cabin system submodel and the powertrain submodel; the construction of the multi-system joint thermal management system model is completed.

[0018] As a preferred embodiment of the technical solution of the present invention, the steps of modifying the cabin system submodel and integrating the modified cabin system submodel with the cooling system submodel through the radiator heat exchange submodel include: Delete the cold side radiator model in the cabin system submodel and the hot side radiator model in the cooling system, and connect the cold and hot sides of the radiator heat exchange model to the cabin system submodel and the cooling system submodel respectively; At the same time, a fan speed control module is added to the cabin system sub-model. The input signal of the fan speed control module is the engine outlet water temperature and the intake air temperature, and the output signal is the fan speed. The engine water outlet temperature and air intake temperature in the cooling system sub-model are input to the input signal port of the fan speed control module to complete the integration of the cabin system sub-model and the cooling system sub-model.

[0019] As a preferred embodiment of the technical solution of the present invention, the cooling system submodel is modified, and the steps of integrating the modified cooling system submodel with the powertrain submodel through the engine heat exchange MAP include: Delete the preset operating conditions of engine speed and torque in the cooling system submodel; An engine heat exchange MAP module is added to the cooling system. The input signal of the engine heat exchange MAP module is the engine speed and torque, and the output signal is the engine heat exchange; The powertrain submodel inputs the engine speed and torque signals to the engine heat exchange MAP module through the databus, completing the integration of the powertrain submodel and the cooling system submodel.

[0020] In a second aspect, the technical solution of the present invention further provides a commercial vehicle thermal management simulation and analysis device, including a power transmission model construction module, a cooling model construction module, a cabin model construction module, a radiator model construction module, a thermal management model construction module and a simulation processing module; Powertrain model building module, used to build a powertrain system sub-model; A cooling model building module is used to build a cooling system sub-model; The cabin model building module is used to build the cabin system sub-model; Radiator model building module, used to build radiator heat transfer sub-model; The thermal management model building module is used to build a multi-system integrated thermal management simulation model after model correction of the constructed powertrain system sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model; The simulation processing module is used to define simulation parameters in the thermal management simulation model, perform simulation calculation analysis and output analysis results.

[0021] As a preferred embodiment of the technical solution of the present invention, the power transmission model construction module is specifically used to drag and drop the power transmission system module from the model library into the simulation window; place each module according to the layout of the whole vehicle, mechanically connect the modules, and then connect the data lines according to the input and output signals; define the structure and performance parameters of each model to generate a power transmission system simulation model; define the simulation conditions, perform vehicle economy simulation, compare the simulation results with the test data, and adjust the constructed power transmission system simulation model to complete the construction of the power transmission system sub-model.

[0022] As a preferred embodiment of the technical solution of the present invention, the cooling model building module is specifically used to establish relevant component models in the simulation software according to the components involved in the vehicle cooling system; establish a pipeline model in the simulation software according to the connection relationship of the actual components; connect the component models through the pipeline model according to the actual pipeline direction and the flow direction of the coolant to build a cooling system simulation model; Define component simulation parameters; establish a component flow resistance model in the simulation software and calibrate the friction coefficient of the flow resistance component; input the preset operating conditions and boundary parameters into the cooling system simulation model and solve to obtain the simulation results; calibrate the flow rate and flow resistance of each branch of the component based on the simulation results to complete the construction of the cooling system sub-model.

[0023] As a preferred embodiment of the technical solution of the present invention, the cabin model construction module is specifically used to establish a one-dimensional cabin model based on the layout structure of relevant components of the cooling module in the engine cabin; drag and drop the inlet pressure boundary, condenser, intercooler, cold side radiator, fan, and outlet pressure boundary modules to the model window in the simulation software and connect each module according to the actual layout, and define each input and output signal connection; establish a component flow resistance model in the simulation software to calibrate the friction coefficient of the flow resistance component; calibrate the headwind volume of the radiator in the model according to the radiator air volume result calculated by the three-dimensional CFD cabin flow field; and complete the construction of the cabin system sub-model.

[0024] As a preferred embodiment of the technical solution of the present invention, a cabin model construction module defines a vehicle speed-fan speed-radiator air volume Map module and a time-vehicle speed Map in the simulation software; sets the P and I parameters and the maximum and minimum values ​​of the PID module; connects the actual value port of the PID module to the one-dimensional simulated air volume value of the radiator, and connects the demand value to the air volume value of the radiator simulated by the three-dimensional CFD; sets a comparison result between the one-dimensional simulated air volume value and the three-dimensional CFD simulated air volume value, and if the error is not within the set range, adjusts the P and I values ​​of the PID for recalibration.

[0025] As a preferred embodiment of the technical solution of the present invention, a radiator model construction module is specifically used to drag and drop the radiator cold side module, the radiator hot side module, the heat exchange unit, the radiator cold and hot side friction coefficient Map and the inlet and outlet boundaries to the simulation window; input the radiator heat dissipation performance data into the heat exchange unit, including the cold side inlet temperature and air volume, the hot side inlet temperature and coolant flow, and the radiator heat exchange capacity; define the flow boundary at the cold side inlet of the radiator, the pressure boundary at the outlet, and the inlet and outlet pressure boundaries on the hot side of the radiator, and calibrate the heat exchange performance of the radiator by correcting the heat exchange coefficient of the heat exchange unit; wherein, the radiator heat exchange sub-model performs cold and hot side modeling through the heat exchange unit, the cold side model is connected to the cold side boundary with which it exchanges heat, and the hot side model is connected to the hot side boundary with which it exchanges heat.

[0026] As a preferred embodiment of the technical solution of the present invention, the thermal management model building module includes a first integrated processing unit, a second integrated processing unit and a third integrated processing unit; A first integration processing unit is used to modify the cabin system sub-model, and integrate the modified cabin system sub-model with the cooling system sub-model through the radiator heat exchange sub-model; A second integrated processing unit is used to modify the cooling system sub-model and integrate the modified cooling system sub-model with the powertrain sub-model through the engine heat exchange MAP; The third integrated processing unit is used to input the vehicle speed signal in the power transmission system sub-model to the vehicle speed input signal port of the inlet pressure boundary of the cabin system sub-model, complete the integration of the cabin system sub-model and the power transmission system sub-model; and complete the construction of the multi-system joint thermal management system model.

[0027] As a preferred embodiment of the technical solution of the present invention, the first integrated processing unit is specifically used to delete the cold side radiator model in the cabin system submodel and the hot side radiator model in the cooling system, and connect the cold and hot sides of the radiator heat exchange model to the cabin system submodel and the cooling system submodel respectively; at the same time, a fan speed control module is added to the cabin system submodel, and the input signals of the fan speed control module are the engine water outlet temperature and the intake air temperature, and the output signal is the fan speed; the engine water outlet temperature and the intake air temperature in the cooling system submodel are input to the input signal port of the fan speed control module to complete the integration of the cabin system submodel and the cooling system submodel.

[0028] As a preferred embodiment of the technical solution of the present invention, the second integrated processing unit is specifically used to delete the preset operating conditions of the engine speed and torque in the cooling system sub-model; add an engine heat exchange MAP module in the cooling system, the input signals of the engine heat exchange MAP module are the engine speed and torque, and the output signal is the engine heat exchange; the power transmission system sub-model inputs the engine speed and torque signals to the engine heat exchange MAP module through the databus; and completes the integration of the power transmission system sub-model and the cooling system sub-model.

[0029] From the above technical solutions, it can be seen that the present invention has the following advantages: the reliability of the vehicle thermal management system can be calculated in the early stage of research and development, and the engine temperature and pressure, and the coolant flow distribution of each branch can be accurately predicted. The thermal management system components can be further selected. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0031] Figure 1 is a schematic flow chart of a method according to an embodiment of the present invention.

[0032] Figure 2 Comparison chart of simulation and test vehicle speed.

[0033] Figure 3 Analysis of engine water temperature and radiator flow results.

[0034] Figure 4 Comparative analysis of fan speed results for different fan control strategies.

[0035] Figure 5 is a schematic block diagram of an apparatus according to an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0037] like Figure 1 As shown, an embodiment of the present invention provides a commercial vehicle thermal management simulation analysis method, comprising the following steps: Step 1: Construct the powertrain sub-model; In the embodiment of the present invention, a powertrain submodel is constructed in the AVL CruiseM software. The engine, clutch, gearbox, drive axle, half shaft, tire, vehicle, driver and cockpit modules are dragged and dropped from the model library to the model window in turn. Then, each module is placed according to the layout of the whole vehicle, and the modules are mechanically connected, and then the data lines are connected according to the input and output signals. At the same time, the universal characteristics of the engine, the gear ratio and efficiency of each gear of the gearbox, the efficiency of the drive axle and other simulation parameters are defined.

[0038] Define the powertrain system simulation conditions for simulation calculation. The simulation conditions include defining the target vehicle speed, target gear, minimum vehicle speed and maximum vehicle speed that change with time in the Proflie module, defining the ambient temperature, humidity and road slope in the Environment module, and defining the start mode and shift time in the Driver module. After the simulation calculation is completed, set the simulation results such as vehicle speed, gear position of the transmission, and fuel consumption per 100 kilometers in the result monitoring interface. Compare the errors between the target vehicle speed and the simulation vehicle speed, the target gear position and the simulation gear position, and the test fuel consumption per 100 kilometers and the simulation fuel consumption per 100 kilometers. The error accuracy is required to be ≤5%.

[0039] Step 2: Construct cooling system sub-model; This step specifically includes the following processes: ① According to the components involved in the vehicle cooling system, select water pump, thermostat, radiator, pipeline, expansion tank and other modules in the cooling and lubrication model library of AVL CruiseM simulation software and drag and drop them into the model window to establish the relevant component models. Among them, the relevant components include engine, water pump, thermostat, oil cooler, turbocharger, radiator, expansion tank.

[0040] ② Establish a pipeline model based on the connection relationship of actual components.

[0041] ③ According to the actual pipeline direction and coolant flow direction, the components are connected through pipelines to build a one-dimensional cooling system simulation model. The cooling system is divided into three branches. Branch I is the coolant flowing from the water pump outlet to the engine, passing through the thermostat and radiator and finally returning to the water pump inlet through the pipeline; branch II is the coolant flowing from the water pump outlet to the oil cooler, and then returning to the water pump inlet through the pipeline; branch III is the coolant flowing from the water pump outlet to the air compressor, and then returning to the water pump inlet through the pipeline.

[0042] ④ Define simulation parameters of related components.

[0043] The structural parameters of the relevant components include: the size of the connecting pipeline, the speed-flow-head map and speed-flow-efficiency map of the water pump, the temperature rise and fall curve of the thermostat and the large and small circulation flow resistance characteristics.

[0044] ⑤ Calibration of component friction coefficient.

[0045] Establish a component flow resistance model in the simulation software, calibrate the friction coefficient, and ensure that the error accuracy of the flow resistance characteristics of the established component model and the test data is within 5%. The components include engines, oil coolers, air compressors, and hot-side radiators; the flow resistance characteristics are the pressure loss of the components at different flow rates, and the hot-side radiator is an internal model of the radiator whose medium is coolant. Replace the calibrated flow resistance component model with the cooling system model. Establish resistance elements such as engines, oil coolers, air compressors, and hot-side radiators in the software. The flow boundary is given at the inlet of the resistance element, and the pressure boundary is given at the outlet of the resistance element. The inlet of the resistance element is connected to the flow boundary, and the outlet is connected to the pressure boundary, and a flow-pressure drop map is established at the same time.

[0046] Set the P and I parameters and the maximum and minimum values ​​of the PID. The actual value port of the PID module is connected to the simulated pressure drop value of the flow resistance element, and the demand value is connected to the pressure drop value of the test flow-pressure drop Map. The comparison result of the simulated pressure drop value and the test pressure drop value is set in the post-processing interface. If the error is within the unacceptable range, adjust the P and I values ​​of the PID for recalibration. After the calibration is completed, the output value of the PID is matched with the friction coefficient of the flow resistance component to produce the flow-friction coefficient Map of the flow resistance element to control the actual pressure drop of the resistance element.

[0047] ⑥ Calibration of cooling system simulation model.

[0048] Input the preset working conditions and boundary parameters of the cooling system simulation model and solve them, including: engine speed and torque, ambient temperature, initial pressure, initial coolant temperature, etc. Set the water pump speed according to the engine speed and water pump speed ratio, and set the cooling system thermostat to a fully open thermostat, that is, the thermostat opening is 1, and define the cooling system as a large cycle working mode. Set the solver to perform steady-state working condition simulation calculations for the cooling system. Analyze the simulated flow and pressure loss of each branch such as the engine, radiator, and oil cooler and the experimental test error. If the error is within an unacceptable range, the friction coefficient of each flow resistance component in ⑤ can be corrected and recalibrated.

[0049] Step 3: Construct the cabin system sub-model; In this step, select the pressure boundary, heat exchanger module, fan module, and MAP module in the AVL CruiseM software gas path module library to build a cabin system simulation sub-model. The specific process is as follows: ① According to the layout structure of the relevant components of the cooling module in the engine compartment, establish a one-dimensional model of the cabin. In the AVLCruiseM software, drag and drop the inlet pressure boundary, condenser, intercooler, cold side radiator, fan, PID controller, outlet pressure boundary and other modules to the model window, connect the modules according to the actual layout, and define the input and output signal connections.

[0050] ② Calibration of component friction coefficient.

[0051] Establish a component flow resistance model in the simulation software and calibrate the friction coefficient. Drag and drop the resistance element, PID controller, flow boundary and pressure boundary on the simulation modeling interface. Connect the flow boundary outlet to the flow resistance element inlet, and connect the flow resistance element outlet to the pressure boundary. Connect the flow boundary to the flow data of the test test, and set the pressure boundary to atmospheric pressure. Set the P and I parameters and maximum and minimum values ​​of the PID. The actual value port of the PID module is connected to the simulated pressure drop value of the flow resistance element, and the demand value is connected to the pressure drop value of the test flow resistance element. The comparison result of the simulated pressure drop value and the test pressure drop value is set in the post-processing interface. If the error between the two is within an unacceptable range, adjust the P and I values ​​of the PID for recalibration. After the calibration is completed, the output value of the PID is matched with the friction coefficient of the flow resistance component to produce the flow-friction coefficient Map of the flow resistance element, and the actual pressure drop of the resistance element is controlled. Ensure that the error accuracy of the flow resistance characteristics of the built component model and the test data is within 5%. The components include a condenser, an intercooler and a cold side radiator. The cold side radiator is an external model of a radiator with air as the medium.

[0052] ③ Calibration of cabin model air volume.

[0053] According to the radiator air volume result calculated by the three-dimensional CFD cabin flow field, the oncoming air volume of the radiator in the cabin system simulation model is calibrated. In the simulation software, define the vehicle speed-fan speed-radiator air volume Map module (Massflow module in the figure) and the time-vehicle speed Map. Among them, the inlet pressure boundary simulates the inlet pressure of the whole vehicle grille. Since the air volume distribution of the cabin system is directly related to the vehicle speed, this pressure boundary needs to input the vehicle speed signal, and the vehicle speed signal comes from the time-vehicle speed Map. Set the P, I parameters and maximum and minimum values ​​of the PID. The actual value port of the PID module is connected to the one-dimensional simulated air volume value of the radiator, and the demand value is connected to the air volume value of the radiator simulated by the three-dimensional CFD. The radiator air volume simulated by the three-dimensional CFD comes from the vehicle speed-fan speed-radiator air volume Map. The comparison results of the one-dimensional simulated air volume value and the three-dimensional CFD simulated air volume value are set in the post-processing interface. If the error is within the unacceptable range, adjust the P and I values ​​of the PID for recalibration.

[0054] Step 4: Construct the heat transfer sub-model of the radiator; In this step, drag and drop the radiator cold side module, radiator hot side module, heat exchange unit, radiator cold and hot side friction coefficient Map, and inlet and outlet boundaries to the simulation modeling interface.

[0055] Input the radiator heat dissipation performance data into the heat exchange unit, including the cold side inlet temperature and air volume, the hot side inlet temperature and coolant flow, and the radiator heat exchange. The cold side inlet of the radiator defines the flow boundary, the outlet defines the pressure boundary, and the hot side of the radiator defines the inlet and outlet pressure boundaries. The heat exchange performance of the radiator is calibrated by correcting the heat exchange coefficient of the heat exchange unit. Ensure that the heat exchange characteristics of the built radiator model and the error accuracy of the test data are within 5%.

[0056] Among them, the radiator heat exchange model is modeled on both the cold and hot sides through the heat exchange unit. The cold side model is connected to the cold side boundary with which it exchanges heat, and the hot side model is connected to the hot side boundary with which it exchanges heat.

[0057] Step 5: After correcting the constructed powertrain system sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model, a multi-system integrated thermal management simulation model is constructed; In this step, building a multi-system integrated thermal management simulation requires model modification of the above systems, including: ① The cabin system and cooling system are integrated through the radiator heat exchange model.

[0058] Delete the cold side radiator model in the cabin system and the hot side radiator model in the cooling system, and connect the cold and hot sides of the radiator heat exchange model to the cabin system and the cooling system respectively. At the same time, add a fan speed control module to the cabin system submodel. The input signal of the fan speed control module is the engine outlet water temperature and the intake air temperature, and the output signal is the fan speed. Input the engine outlet water temperature and the intake air temperature in the cooling system to the input signal port of the fan speed control module. Complete the integration of the cabin system and the cooling system submodel.

[0059] ② The cooling system is integrated with the powertrain through the engine heat exchange MAP.

[0060] Delete the preset working conditions of engine speed and torque in the cooling system simulation sub-model. Add an engine heat exchange MAP module to the cooling system. The engine heat exchange MAP input signal is the engine speed and torque, and the output signal is the engine heat exchange. The powertrain system inputs the engine speed and torque signals to the engine heat exchange MAP module through the databus. The integration of the powertrain system and the cooling system is completed through the above model modification.

[0061] ③ The cabin system and powertrain system are integrated through vehicle speed signals.

[0062] The vehicle speed signal in the powertrain submodel is input to the vehicle speed input signal port of the cabin system inlet pressure boundary, and the integration of the cabin system and the powertrain system is completed through the above model modification.

[0063] ④ Through the integration of simulation sub-models such as the cooling system, cabin system and power transmission system, a multi-system joint thermal management system model is constructed. Step 6: Define simulation parameters in the thermal management simulation model to perform simulation calculation analysis and output the analysis results.

[0064] After completing the above steps, define the simulation calculation operating conditions, ambient temperature boundaries and other parameters in the multi-system integrated thermal management model. Establish post-processing result analysis in the simulation software and establish a comparison curve between the test vehicle speed and the simulation vehicle speed, such as Figure 2 As shown in the figure, analyze whether the simulated vehicle speed can match the test vehicle speed. Establish the simulation result curve of cooling system water temperature and radiator flow, as shown in the figure. Figure 3 As shown in the figure, the cooling system simulation analysis is used to obtain the cooling system engine water temperature and radiator flow results. A comparison curve of fan speed results under different fan strategies is established, as shown in the figure. Figure 4As shown in the figure, the impact of fan strategy on thermal management is analyzed by comparing the fan speed results. The simulation model is not limited to the analysis of the above simulation results. Other results involved in vehicle thermal management simulation can be analyzed according to the simulation objectives and requirements. The analysis results are checked to see whether they meet the evaluation requirements related to thermal management and vehicle economy. If the results do not meet the requirements, relevant design and control strategy optimization can be performed. The multi-system integrated simulation platform can quickly iterate and verify the optimization plan.

[0065] like Figure 5 As shown, an embodiment of the present invention further provides a commercial vehicle thermal management simulation and analysis device, including a power transmission model building module, a cooling model building module, a cabin model building module, a radiator model building module, a thermal management model building module and a simulation processing module; Powertrain model building module, used to build a powertrain system sub-model; A cooling model building module is used to build a cooling system sub-model; The cabin model building module is used to build the cabin system sub-model; Radiator model building module, used to build radiator heat transfer sub-model; The thermal management model building module is used to build a multi-system integrated thermal management simulation model after model correction of the constructed powertrain system sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model; The simulation processing module is used to define simulation parameters in the thermal management simulation model, perform simulation calculation analysis and output analysis results.

[0066] In some embodiments, the power transmission model construction module is specifically used to drag and drop the power transmission system module from the model library into the simulation window; place the modules according to the layout of the whole vehicle, mechanically connect the modules, and then connect the data lines according to the input and output signals; define the structure and performance parameters of each model to generate a power transmission system simulation model; define the simulation conditions, perform vehicle economy simulation, compare the simulation results with the test data, and adjust the constructed power transmission system simulation model to complete the construction of the power transmission system sub-model.

[0067] In some embodiments, the cooling model building module is specifically used to build relevant component models in the simulation software according to the components involved in the vehicle cooling system; build a pipeline model in the simulation software according to the connection relationship of the actual components; connect the component models through the pipeline model according to the actual pipeline direction and the flow direction of the coolant to build a cooling system simulation model; Define component simulation parameters; establish a component flow resistance model in the simulation software and calibrate the friction coefficient of the flow resistance component; input the preset operating conditions and boundary parameters into the cooling system simulation model and solve to obtain the simulation results; calibrate the flow rate and flow resistance of each branch of the component based on the simulation results to complete the construction of the cooling system sub-model.

[0068] In some embodiments, the cabin model construction module is specifically used to establish a one-dimensional cabin model based on the layout structure of related components of the cooling module in the engine cabin; drag and drop the inlet pressure boundary, condenser, intercooler, cold side radiator, fan, and outlet pressure boundary modules to the model window in the simulation software and connect each module according to the actual layout, and define each input and output signal connection; establish a component flow resistance model in the simulation software to calibrate the friction coefficient of the flow resistance component; calibrate the headwind volume of the radiator in the model according to the radiator air volume result calculated by the three-dimensional CFD cabin flow field; and complete the construction of the cabin system sub-model.

[0069] In some embodiments, a cabin model construction module defines a vehicle speed-fan speed-radiator air volume Map module and a time-vehicle speed Map in the simulation software; sets the P and I parameters and the maximum and minimum values ​​of the PID module; connects the actual value port of the PID module to the one-dimensional simulated air volume value of the radiator, and connects the demand value to the air volume value of the radiator simulated by the three-dimensional CFD; sets a comparison result between the one-dimensional simulated air volume value and the three-dimensional CFD simulated air volume value, and if the error is not within the set range, adjusts the P and I values ​​of the PID for recalibration.

[0070] In some embodiments, the radiator model construction module is specifically used to drag and drop the radiator cold side module, the radiator hot side module, the heat exchange unit, the radiator cold and hot side friction coefficient Map and the inlet and outlet boundaries to the simulation window; input the radiator heat dissipation performance data into the heat exchange unit, including the cold side inlet temperature and air volume, the hot side inlet temperature and coolant flow, and the radiator heat exchange capacity; define the flow boundary at the cold side inlet of the radiator, the pressure boundary at the outlet, and the inlet and outlet pressure boundaries on the hot side of the radiator, and calibrate the heat exchange performance of the radiator by correcting the heat exchange coefficient of the heat exchange unit; wherein, the radiator heat exchange sub-model performs cold and hot side modeling through the heat exchange unit, the cold side model is connected to the cold side boundary with which it exchanges heat, and the hot side model is connected to the hot side boundary with which it exchanges heat.

[0071] In some embodiments, the thermal management model building module includes a first integrated processing unit, a second integrated processing unit, and a third integrated processing unit; A first integration processing unit is used to modify the cabin system sub-model, and integrate the modified cabin system sub-model with the cooling system sub-model through the radiator heat exchange sub-model; A second integrated processing unit is used to modify the cooling system sub-model and integrate the modified cooling system sub-model with the powertrain sub-model through the engine heat exchange MAP; The third integrated processing unit is used to input the vehicle speed signal in the power transmission system sub-model to the vehicle speed input signal port of the inlet pressure boundary of the cabin system sub-model, complete the integration of the cabin system sub-model and the power transmission system sub-model; and complete the construction of the multi-system joint thermal management system model.

[0072] The first integrated processing unit is specifically used to delete the cold side radiator model in the cabin system submodel and the hot side radiator model in the cooling system, and connect the cold and hot sides of the radiator heat exchange model to the cabin system submodel and the cooling system submodel respectively; at the same time, a fan speed control module is added to the cabin system submodel, and the input signals of the fan speed control module are the engine water outlet temperature and the intake air temperature, and the output signal is the fan speed; the engine water outlet temperature and the intake air temperature in the cooling system submodel are input to the input signal port of the fan speed control module to complete the integration of the cabin system submodel and the cooling system submodel.

[0073] The second integrated processing unit is specifically used to delete the preset working conditions of the engine speed and torque in the cooling system sub-model; add an engine heat exchange MAP module in the cooling system, the input signal of the engine heat exchange MAP module is the engine speed and torque, and the output signal is the engine heat exchange; the power transmission system sub-model inputs the engine speed and torque signals to the engine heat exchange MAP module through the databus; and completes the integration of the power transmission system sub-model and the cooling system sub-model.

[0074] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0075] An embodiment of a commercial vehicle whole vehicle thermal management simulation and analysis device provided in an embodiment of the present invention belongs to the same inventive concept as the commercial vehicle whole vehicle thermal management simulation and analysis methods of the above-mentioned embodiments. For details not fully described in the embodiment of the commercial vehicle whole vehicle thermal management simulation and analysis device, reference can be made to the embodiment of the above-mentioned commercial vehicle whole vehicle thermal management simulation and analysis method.

[0076] Although the present invention has been described in detail with reference to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person of ordinary skill in the art may easily think of changes or substitutions within the technical scope disclosed by the present invention, and these shall be within the scope of protection of the present invention.

Claims

1. A commercial vehicle thermal management simulation analysis method, characterized in that: The steps include: Construct the powertrain sub-model; Construct cooling system sub-model; Construct the cabin system sub-model; Construct the heat transfer sub-model of the radiator; After model corrections are made to the constructed powertrain sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model, a multi-system integrated thermal management simulation model is constructed; Define simulation parameters in the thermal management simulation model to perform simulation calculation analysis and output the analysis results.

2. The commercial vehicle thermal management simulation analysis method according to claim 1 is characterized in that: The steps to build the powertrain submodel include: Drag the powertrain module from the model library and drop it into the simulation window; Place each module according to the vehicle layout, make mechanical connections between the modules, and then make data line connections according to input and output signals; meanwhile, define the structure and performance parameters of each model to generate a powertrain simulation model; Define simulation conditions, conduct vehicle economy simulation, compare simulation results with test data, adjust the constructed powertrain simulation model to complete the construction of the powertrain sub-model.

3. The commercial vehicle thermal management simulation analysis method according to claim 2 is characterized in that: The steps to build the cooling system submodel include: According to the components involved in the vehicle cooling system, establish relevant component models in the simulation software; Establish a pipeline model in the simulation software based on the connection relationship of actual components; According to the actual pipeline direction and coolant flow direction, the component models are connected through the pipeline model to build a cooling system simulation model; Define component simulation parameters; Establish a component flow resistance model in the simulation software and calibrate the friction coefficient of the flow resistance component; Input the preset working conditions and boundary parameters into the cooling system simulation model and solve it to obtain the simulation results; Based on the simulation results, the flow rate and flow resistance of each branch of the component are calibrated to complete the construction of the cooling system sub-model.

4. The commercial vehicle thermal management simulation analysis method according to claim 3 is characterized in that: The steps to build the cabin system submodel include: According to the layout structure of the relevant components of the cooling module in the engine compartment, a one-dimensional model of the compartment is established; In the simulation software, drag and drop the inlet pressure boundary, condenser, intercooler, cold side radiator, fan, and outlet pressure boundary modules to the model window and connect the modules according to the actual layout, and define the input and output signal connections; Establish a component flow resistance model in the simulation software and calibrate the friction coefficient of the flow resistance component; According to the radiator air volume results calculated by the three-dimensional CFD cabin flow field, the headwind air volume of the radiator in the model is calibrated; the construction of the cabin system submodel is completed.

5. The commercial vehicle thermal management simulation analysis method according to claim 4 is characterized in that: According to the radiator air volume results calculated by the three-dimensional CFD cabin flow field, the steps for calibrating the headwind air volume of the radiator in the model include: Define the vehicle speed-fan speed-radiator air volume map module and time-vehicle speed map in the simulation software; Set the P and I parameters and the maximum and minimum values ​​of the PID module; Connect the actual value port of the PID module to the one-dimensional simulated air volume value of the radiator, and connect the demand value to the air volume value of the radiator simulated by three-dimensional CFD; Set the comparison results of the one-dimensional simulated air volume value and the three-dimensional CFD simulated air volume value. If the error is not within the set range, adjust the P and I values ​​of the PID for recalibration.

6. The commercial vehicle thermal management simulation analysis method according to claim 5 is characterized in that: The steps to build the radiator heat transfer submodel include: Drag and drop the radiator cold side module, radiator hot side module, heat exchange unit, radiator cold and hot side friction coefficient map and inlet and outlet boundaries to the simulation window; Input the radiator heat dissipation performance data into the heat exchange unit, including the cold side inlet temperature and air volume, the hot side inlet temperature and coolant flow, and the radiator heat exchange capacity; The flow boundary is defined at the inlet of the cold side of the radiator, the pressure boundary is defined at the outlet, and the inlet and outlet pressure boundaries are defined at the hot side of the radiator. The heat transfer performance of the radiator is calibrated by correcting the heat transfer coefficient of the heat exchange unit. Among them, the radiator heat exchange sub-model performs cold and hot side double-side modeling through the heat exchange unit. The cold side model is connected to the cold side boundary with which it exchanges heat, and the hot side model is connected to the hot side boundary with which it exchanges heat.

7. The commercial vehicle thermal management simulation analysis method according to claim 6 is characterized in that: The steps of constructing a multi-system integrated thermal management simulation model after model correction of the constructed powertrain sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model include: The cabin system submodel is modified, and the modified cabin system submodel is integrated with the cooling system submodel through the radiator heat exchange submodel; Modify the cooling system submodel, and integrate the modified cooling system submodel with the powertrain submodel through the engine heat exchange MAP; The vehicle speed signal in the powertrain submodel is input to the vehicle speed input signal port of the inlet pressure boundary of the cabin system submodel to complete the integration of the cabin system submodel and the powertrain submodel; the construction of the multi-system joint thermal management system model is completed.

8. The commercial vehicle thermal management simulation analysis method according to claim 7 is characterized in that: The steps of modifying the cabin system submodel and integrating the modified cabin system submodel with the cooling system submodel through the radiator heat exchange submodel include: Delete the cold side radiator model in the cabin system submodel and the hot side radiator model in the cooling system, and connect the cold and hot sides of the radiator heat exchange model to the cabin system submodel and the cooling system submodel respectively; At the same time, a fan speed control module is added to the cabin system sub-model. The input signal of the fan speed control module is the engine outlet water temperature and the intake air temperature, and the output signal is the fan speed. The engine water outlet temperature and air intake temperature in the cooling system sub-model are input to the input signal port of the fan speed control module to complete the integration of the cabin system sub-model and the cooling system sub-model.

9. The commercial vehicle thermal management simulation analysis method according to claim 8, characterized in that: The steps of modifying the cooling system submodel and integrating the modified cooling system submodel with the powertrain submodel through the engine heat exchange MAP include: Delete the preset operating conditions of engine speed and torque in the cooling system submodel; An engine heat exchange MAP module is added to the cooling system. The input signal of the engine heat exchange MAP module is the engine speed and torque, and the output signal is the engine heat exchange; The powertrain submodel inputs the engine speed and torque signals to the engine heat exchange MAP module through the databus, completing the integration of the powertrain submodel and the cooling system submodel.

10. A commercial vehicle thermal management simulation analysis device, characterized in that: It includes a powertrain model building module, a cooling model building module, a cabin model building module, a radiator model building module, a thermal management model building module and a simulation processing module; Powertrain model building module, used to build a powertrain system sub-model; A cooling model building module is used to build a cooling system sub-model; The cabin model building module is used to build the cabin system sub-model; Radiator model building module, used to build radiator heat transfer sub-model; The thermal management model building module is used to build a multi-system integrated thermal management simulation model after model correction of the constructed powertrain system sub-model, cooling system sub-model, cabin system sub-model and radiator heat exchange sub-model; The simulation processing module is used to define simulation parameters in the thermal management simulation model, perform simulation calculation analysis and output analysis results.

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