Method for optimizing synergistic cooling efficiency of an intercooler and an EGR system
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- XIAN JIAHE HUAHENG THERMAL SYST CO LTD
- Filing Date
- 2026-03-25
- Publication Date
- 2026-06-02
Smart Images
Figure CN121897454B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of internal combustion engine thermal management technology, and relates to a method for optimizing the synergistic cooling efficiency of the intercooler and EGR system. Background Technology
[0002] In modern internal combustion engine technology, the intercooler and exhaust gas recirculation (EGR) system are key components for improving engine performance and meeting stringent emission regulations. The intercooler cools the high-temperature intake air after turbocharging, increasing intake air density and thus boosting engine power output. The EGR system, by reintroducing a portion of the cooled exhaust gas into the cylinders for combustion, lowers the peak temperature and oxygen concentration within the combustion chamber, effectively suppressing nitrogen oxide (NOx) formation. The operational status of these two systems directly impacts the engine's fuel supply strategy and final combustion efficiency.
[0003] In existing technologies, the intercooler system and the EGR system typically employ independent control schemes for cooling. The intercooler's cooling circuit and the EGR cooler's cooling circuit each have independent or partially shared coolant circulation paths, and are independently adjusted by the engine control unit according to their respective control objectives. For example, the intercooler's control objective is to minimize the boosted intake air temperature, while the EGR cooler's control objective is to cool the high-temperature exhaust gas to a target temperature. There is a lack of direct coordination and coupling between the two in terms of control logic and physical linkage.
[0004] However, this independent control method has inherent technical drawbacks. First, due to the separation of control logic, the two systems are prone to conflicts in thermal management resources when facing complex and changing operating conditions. For example, when maximum cooling capacity is required simultaneously, it will increase the burden on the engine's main cooling system. Second, the system response is lagging, unable to make rapid and proactive adjustments to transient changes in the engine, causing combustion conditions to deviate from optimal conditions for a short period of time. In addition, a large amount of waste heat in the EGR system is simply dissipated into the environment by the EGR cooler, resulting in energy waste and failing to reuse it as a usable resource. Summary of the Invention
[0005] In order to overcome the above-mentioned defects of the prior art and to achieve the above objectives, the present invention proposes the following technical solution: a method for optimizing the coordinated cooling efficiency of intercooler and EGR system, comprising: S1, acquiring engine operating parameters, vehicle operating status parameters and external environmental parameters, and fusing them into a real-time status data stream.
[0006] S2. Input the real-time status data stream into the multi-objective predictive control model used to predict the future operating trend of the engine, and generate prediction results including future heat load, emission generation trend and fuel consumption rate.
[0007] S3. Based on the prediction results, the optimal thermal management coupler heat exchange demand sequence in the prediction time domain is calculated using a function that minimizes the overall performance.
[0008] S4. Extract the current value from the heat exchange demand sequence of the preferred thermal management coupler, and generate a flow regulation command based on the current value.
[0009] S5. Execute the flow regulation command to control the three-way regulating valve, dynamically adjust the flow rate of the intercooler coolant flowing through the thermal management coupler, and generate the real-time adjusted flow rate.
[0010] S6. Within the thermal management coupler, the engine high-temperature coolant is guided to flow through its first flow channel, and the intercooler coolant with real-time adjustable flow rate is guided to flow through its second flow channel for heat exchange to output pre-cooled high-temperature coolant and pre-heated intercooler coolant.
[0011] S7. The pre-cooled high-temperature coolant is delivered to the EGR cooler for deep cooling of the EGR exhaust gas.
[0012] S8. Introduce preheated intercooler coolant into the intercooler cooling circuit to regulate the boost intake air temperature.
[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention achieves the synergistic optimization of the overall performance of the engine by establishing a collaborative working mechanism between the intercooler and the EGR system. This method couples two originally independent systems that have potential conflicts in thermal management requirements. By predictively adjusting the thermal energy distribution, it enables energy scheduling to be carried out in advance using the intercooler circuit when it is necessary to enhance EGR cooling to reduce emissions, and vice versa. This solves the problem of mutual constraints between reducing emissions and improving fuel economy in the traditional control strategy.
[0014] (2) This invention introduces a control strategy based on multi-objective prediction, which improves the dynamic adaptability and control accuracy of the thermal management system. By sensing the comprehensive status of the engine, vehicle and environment in real time and predicting future operating conditions, the optimal heat exchange strategy can be formulated in advance. This enables the system to maintain efficient and stable operation when facing transient conditions such as rapid acceleration or sudden load changes, ensuring that the combustion conditions are always in the optimal range.
[0015] (3) This invention achieves the redistribution and efficient utilization of internal engine heat energy by setting up a thermal management coupler. This method transfers the high-grade heat energy that would otherwise be lost in the EGR cooling circuit to the intercooler cooling circuit for precise temperature regulation of the boosted intake air under specific operating conditions. This recycling of internal energy reduces the dependence on the total heat dissipation capacity of the cooling system, reduces the energy consumption of cooling accessories, and thus improves the overall thermal efficiency of the engine. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the implementation steps of the method of the present invention. Detailed Implementation
[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0019] Please see Figure 1 As shown, the present invention proposes a method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system, which includes: S1, acquiring engine operating parameters, vehicle operating status parameters and external environmental parameters, and fusing them into a real-time status data stream.
[0020] In a preferred embodiment, the acquisition of engine operating parameters, vehicle operating status parameters, and external environmental parameters, and their integration into a real-time status data stream, includes: collecting engine speed parameters, load parameters, and temperature parameters through a sensor array to form engine operating parameters.
[0021] The vehicle's operating status parameters are obtained via the vehicle bus, including current vehicle speed parameters, vehicle load parameters, and the driver's acceleration or deceleration intentions.
[0022] External environmental parameters are obtained by using external environmental sensors to obtain environmental temperature and humidity parameters.
[0023] The engine operating parameters, vehicle operating status parameters, and external environmental parameters are timestamped and integrated into a real-time status data stream.
[0024] Specifically, multiple sensors integrated into the engine body and accessories physically collect engine operating parameters, including: using a crankshaft position sensor mounted on the crankshaft or flywheel to directly obtain engine speed parameters, which characterize the engine's operating speed, by monitoring the frequency of its output pulse signal; using an absolute pressure sensor installed in the intake manifold or an air flow sensor in the intake pipeline to collect intake pressure or flow data, and combining this with the current engine speed, the engine control unit calculates engine load parameters that accurately reflect the engine's power intensity and output capacity based on a preset engine universal characteristic spectrum; and using a thermistor temperature sensor arranged in the engine coolant main circulation channel to directly measure the real-time temperature of the coolant, which serves as the engine temperature parameter characterizing the overall thermal state of the engine.
[0025] The vehicle's macroscopic operating status parameters are acquired non-intrusively via the vehicle's controller local area network bus. The vehicle's central controller parses the current vehicle speed parameters calculated by the wheel speed sensors from the data frames broadcast by the anti-lock braking system or vehicle stability control system module. Simultaneously, based on the actual output torque provided by the engine control unit, vehicle acceleration sensor signals, and preset vehicle model parameters (such as vehicle mass, drag coefficient, rolling resistance coefficient, etc.), the controller calculates the comprehensive driving resistance borne by the entire vehicle in real time and quantifies it as vehicle load parameters. In addition, the signal obtained from the pedal position sensor integrated with the electronic accelerator pedal assembly directly reflects the driver's acceleration or deceleration intention, i.e., the accelerator pedal opening parameter.
[0026] External environmental parameters are acquired through a dedicated sensor array installed at the front of the vehicle, such as in the front bumper or rearview mirror. This sensor array includes: a thermistor thermometer to measure the ambient temperature of the surrounding air, serving as the ambient temperature parameter; and a capacitive or resistive humidity sensor to measure the relative humidity of the air, serving as the ambient humidity parameter.
[0027] Within the central processing unit, all the parameters independently acquired and calculated are fused. This fusion process involves attaching a uniform timestamp to each parameter from different sources, integrating these discrete data points acquired at the same time or within a very short time window into a structured data vector. This vector is the real-time state data stream, which can be represented as a state vector. ,in, Represents the current timestamp; The engine speed at the current timestamp; Engine load at the current timestamp; The engine temperature at the current timestamp; The vehicle speed at the current timestamp; Vehicle load at the current timestamp; The accelerator pedal opening at the current timestamp; The ambient temperature at the current timestamp; The ambient humidity is at the current timestamp. This real-time state data stream, as a complete and synchronous snapshot of the system state, is continuously generated and provided to subsequent predictive control models.
[0028] This method constructs a comprehensive and synchronous real-time status data stream, organically integrating previously isolated information from the engine, vehicle, and external environment, providing an accurate input foundation for subsequent prediction and control. This multi-dimensional data fusion enables the control system to accurately understand the engine's comprehensive operating status under specific driving behaviors and environmental conditions. Therefore, subsequent predictive models can make more accurate judgments about future trends, thus giving the entire collaborative cooling strategy foresight and adaptability to operating conditions. This fundamentally improves control accuracy and overall system energy efficiency, laying a solid data foundation for achieving synergistic optimization of emissions, fuel consumption, and thermal management performance.
[0029] S2. Input the real-time status data stream into the multi-objective predictive control model used to predict the future operating trend of the engine, and generate prediction results including future heat load, emission generation trend and fuel consumption rate.
[0030] In a preferred embodiment, the step of inputting the real-time status data stream into a multi-objective predictive control model for predicting the future operating trend of the engine, and generating a prediction result including future heat load, emission generation trend and fuel consumption rate, includes: taking the real-time status data stream as input, and using the heat load prediction sub-model integrated within the multi-objective predictive control model to identify and quantify the changing trend of the engine's future heat load.
[0031] The generated future heat load change trend, along with the original real-time status data stream, is fed into the emission and fuel consumption prediction sub-model within the multi-objective predictive control model to determine the emission generation trend and fuel consumption rate.
[0032] Based on the real-time status data stream, the current operating mode of the engine is determined by a preset operating condition identifier. The operating modes include economic cruise mode, power climbing mode, or cold start warm-up mode.
[0033] Based on the engine's current operating mode, a set of corresponding dynamic weight vectors is retrieved from a preset weight lookup table.
[0034] The predicted trends in heat load, emissions generation, and fuel consumption rate, along with this set of dynamic weight vectors, constitute the final output prediction result.
[0035] Specifically, the multi-objective predictive control model in this invention has been trained and calibrated offline using a large amount of historical operating data and machine learning methods before it is put into use.
[0036] First, the multi-objective predictive control model receives real-time status data streams as input and uses its internally integrated heat load prediction sub-model to identify and quantify the future heat load variation trend of the engine. The heat load prediction sub-model preferably employs algorithms capable of processing time-series data, such as recurrent neural network structures like Long Short-Term Memory networks or gated recurrent units. It can deduce the heat sequence that the engine will generate at each control step within a preset prediction time domain from the complex temporal dependencies in the input data stream; this sequence represents the heat load variation trend. The preset prediction time domain is typically several seconds to tens of seconds into the future, with each step being 0.5 seconds.
[0037] Next, the newly generated future heat load change trend, along with the original real-time status data stream, is fed into the emission and fuel consumption prediction sub-model within the multi-objective predictive control model. These two sub-models, based on the mapping relationship between engine mechanism and experimental data calibration, can calculate the emission trends of pollutants such as nitrogen oxides and the fuel consumption rate per unit time under a specific heat load trend.
[0038] Then, based on key indicators in the real-time status data stream, such as the amplitude and rate of change of the accelerator pedal opening, the universal characteristic diagram range of engine speed and load, and vehicle speed stability, the system uses a preset operating condition identifier to determine the engine's operating mode in real time, such as economic cruise mode, power climbing mode, or cold start warm-up mode.
[0039] Based on the identified operating mode, the system retrieves a set of corresponding dynamic weight vectors from a preset weight lookup table. The components of this dynamic weight vector These correspond to the three optimization objectives—thermal management efficiency, emission control, and fuel economy—at the k-th discrete time step within the prediction time domain, representing their importance or priority under the current operating mode. Here, k is the number of each discrete time step within the prediction time domain. For example, in a rapid acceleration power mode, to ensure power response, the weight of fuel economy is... It will be higher; in the economic mode of low-speed cruising in the city, the weight of emission control will be higher. Then it may be assigned a higher value; while in extreme thermal load modes such as long-term heavy-load uphill climbing or continuous high-load operation in high-temperature environments, thermal management efficiency to prevent engine overheating and ensure stable system operation becomes the primary objective, and its weight is lower. It will be set to the highest level.
[0040] Finally, the three predicted future trend sequences—heat load change trend, emissions generation trend, and fuel consumption rate—are combined with this set of dynamic weight vectors to form a structured data package, which is the final output prediction result, providing a decision basis for the next step of optimization calculation.
[0041] This method, by introducing a dynamic prediction mechanism based on real-time operating conditions, achieves a shift in control philosophy from passive response to proactive prediction. This enables the control system to anticipate future changes in operating conditions and prepare in advance, rather than performing delayed compensation after problems occur. In particular, through dynamic weight adjustment, the system can intelligently switch optimization priorities based on driver intent and vehicle status. For example, it prioritizes power response and fuel economy when rapid acceleration is needed, while focusing on emission control and thermal efficiency during steady-state cruising. This achieves a flexible and optimal balance between multiple mutually constraining performance objectives under different operating conditions. This combination of foresight and adaptability makes the entire thermal management system's operating trajectory closer to the ideal state, providing core intelligent decision support for achieving globally optimized synergistic cooling effects, thereby improving the system's overall performance and environmental adaptability.
[0042] S3. Based on the prediction results, the optimal thermal management coupler heat exchange demand sequence in the prediction time domain is calculated using a function that minimizes the overall performance.
[0043] In a preferred embodiment, calculating the optimal thermal management coupler heat exchange demand sequence in the prediction time domain includes: constructing a comprehensive performance objective function based on the future heat load, emission generation trends, and fuel consumption rate in the prediction results.
[0044] Within the rolling time window, the comprehensive performance objective function is solved using an algorithm for solving constrained optimization problems, generating a sequence of optimal thermal management coupler heat exchange requirements.
[0045] In each control cycle, the optimal thermal management coupler heat exchange demand sequence is updated using the latest forecast results.
[0046] Specifically, the step of calculating the optimal heat exchange demand sequence based on the prediction results in this invention is essentially solving a constrained dynamic optimization problem within the model predictive control framework.
[0047] First, construct a comprehensive performance objective function. This function is a comprehensive consideration of the overall performance of the system in terms of future thermal management, emissions, and fuel consumption within the future prediction time domain, and its form can be expressed as: , where the summation symbol Σ represents the accumulation of all discrete time steps over the entire prediction time domain starting from the current moment; The total cost represents the overall performance, and the optimization objective is to minimize it. and These are the normalized predicted values obtained from the emission generation trend and fuel consumption rate obtained in the previous step, after being normalized by dividing them by their respective maximum allowable value or benchmark value under typical operating conditions, in order to ensure the additivity of different physical quantities. These are dynamic weights obtained from the prediction results and that change dynamically with the operating conditions, reflecting the control emphasis on thermal management efficiency, emission control, and fuel economy at the k-th discrete time step. Represents adjacent time steps arrive The normalized value of the rate of change of heat exchange demand, as a control variable, is used to smooth out drastic fluctuations in control commands. Its source is... , Representing the first The and the first The ideal heat exchange power for each control step is calculated within the corresponding control cycle based on the predictive control model adopted in this invention; the objective function is introduced with respect to... The square of the value is a penalty for drastic changes in the control quantity. Its function is to smooth out fluctuations in the control command, avoid frequent impacts on the actuator of the three-way regulating valve, and ensure the smoothness of the control process and the mechanical stability of the system.
[0048] Subsequently, the system employs a rolling optimization algorithm, such as the sequential quadratic programming algorithm commonly used in model predictive control, to solve the aforementioned optimization problem. Based on the model in the prediction results, this algorithm, under the premise of satisfying various physical constraints of the engine, such as the engine coolant temperature not exceeding 110℃, the EGR cooling temperature being below 150℃, and the three-way regulating valve opening between 0-100%, it iteratively calculates to find a set of heat exchange demand control quantities that minimize the overall performance objective function. This set of values arranged in chronological order constitutes the optimal heat exchange demand sequence for the thermal management coupler within the current prediction time domain: {u(1),u(2),...,u(k)...,u(N)}. Each element in the sequence represents the expected heat exchange power value in the thermal management coupler at the k-th control step in the future, where N is the total number of control steps within the future prediction time domain. This value is directional: a positive value indicates that heat needs to be transferred from the engine's high-temperature coolant to the intercooler coolant, i.e., "pre-cooling" the high-temperature coolant and "pre-heating" the intercooler coolant. When the optimization algorithm calculates a negative value, given that the intercooler cooling circuit temperature is much lower than the engine's high-temperature circuit under normal operating conditions, spontaneous reverse heat transfer cannot be achieved due to the second law of thermodynamics. Therefore, the control system will truncate the negative value command to zero at the physical execution level. This means that the three-way regulating valve will completely cut off the flow to the thermal management coupler, thereby avoiding the output of invalid or physically illegal regulating commands. Only when in extreme conditions such as cold start without engine warm-up and physical temperature reversal, is a negative value executed as a reverse heat exchange action. A zero value indicates that at this moment, no heat exchange is required between the two cooling circuits, and the thermal management coupler is in a bypass or non-operating state.
[0049] Finally, this calculation process is repeated within each control cycle. That is, at the beginning of each new cycle, the system obtains the latest real-time status data stream and prediction results, and recalculates a completely new optimal thermal management coupler heat exchange demand sequence, thereby realizing real-time updates and rolling forward of the control strategy.
[0050] This method transforms prediction into an optimal action strategy by constructing and solving a dynamic, comprehensive performance objective function. It abandons traditional control methods based on static rules or single-objective compromises, instead employing an optimization decision-making mechanism based on a global and future-oriented perspective. Through rolling optimization, the system not only finds the optimal control input for the current moment but also pre-plans the optimal control path for a period in the future, ensuring that each adjustment serves the overall long-term goal rather than a short-sighted local optimization based on the current moment. This mechanism enables the control system to find a dynamic, condition-adaptive optimal balance between conflicting performance indicators, such as reducing emissions and saving fuel. Simultaneously, by introducing penalties for changes in the control input into the objective function, the smoothness of the control output is guaranteed, frequent shocks to the actuators are avoided, and the stability and durability of the entire system are enhanced.
[0051] S4. Extract the current value from the heat exchange demand sequence of the preferred thermal management coupler, and generate a flow regulation command based on the current value.
[0052] In a preferred embodiment, the step of extracting the current value from the preferred thermal management coupler heat exchange demand sequence and generating a flow regulation command based on the current value includes: converting the current value of the preferred thermal management coupler heat exchange demand sequence into a flow rate setpoint.
[0053] The actual flow rate feedback value through the thermal management coupler is obtained by a flow sensor.
[0054] The flow setpoint and actual flow feedback value are input to the controller used for closed-loop control, which calculates and outputs flow regulation commands.
[0055] Specifically, the process of generating flow regulation commands based on the current value of the preferred heat exchange demand sequence in this invention is a typical closed-loop feedback control implementation process.
[0056] First, the controller extracts the first element of the optimal thermal management coupler heat exchange demand sequence, i.e., the current value. This current value represents the ideal heat exchange power within the current control cycle. Through a preset physical conversion model, this current value, expressed in heat units, is converted into a specific physical quantity, namely the intercooler coolant flow rate setpoint. This conversion is based on the fundamental principle of heat exchange, that is, the required heat exchange power is proportional to the product of the fluid mass flow rate and the temperature difference. When the temperature difference is measurable or estimable, the target flow rate can be calculated.
[0057] Secondly, in order to achieve closed-loop control, the system uses a flow sensor, such as a turbine flow meter or an electromagnetic flow meter, installed on the coolant flow path of the intercooler to measure the actual coolant flow rate through the thermal management coupler in real time. This measured value is the actual flow feedback value.
[0058] Next, the system compares the setpoint flow rate with the actual flow rate feedback value to obtain the deviation signal between the two. The deviation signal is input to a standard proportional-integral-derivative (PID) controller. This PID controller calculates the output based on the following classic control law. ,in, The final flow regulation command is typically the duty cycle of a voltage signal or a pulse width modulation signal. This is the traffic deviation at the current timestamp; This represents any specific historical moment within the entire integration time period from the control start point (time 0) to the current time (time t). The instantaneous flow deviation value; These are the proportional, integral, and derivative gain coefficients, which are tuned during the system design phase through mathematical modeling and simulation analysis of the dynamic characteristics of the thermal management system to ensure that the control system has good speed, accuracy, and stability. The derivation logic of this formula incorporates the response to three different dimensions of error: the proportional term (… Provides an immediate response proportional to the current deviation; the integral term ( ) is responsible for eliminating steady-state errors caused by inaccurate system models or external disturbances, ensuring that the flow rate ultimately reaches the set value precisely; the differential term ( The system predicts future trends by measuring the rate of change of response deviation, thereby suppressing overshoot and improving the dynamic stability of the system.
[0059] This method, by introducing closed-loop feedback control, accurately translates upper-level optimization decisions into physical execution actions, solving the problem of having only optimization objectives but lacking precise execution methods. Through real-time feedback and PID control, this method can overcome various uncertainties in the system, such as changes in coolant viscosity, pump performance degradation, or pipeline pressure fluctuations, ensuring that the actual coolant flow rate can quickly, stably, and accurately track the dynamic target value given by the optimization algorithm. This high-fidelity execution capability is the foundation for the successful implementation of the entire collaborative cooling strategy. It translates macroscopic optimization intentions into microscopic physical control, enabling the performance advantages brought by prediction and optimization to be fully realized.
[0060] S5. Execute the flow regulation command to control the three-way regulating valve, dynamically adjust the flow rate of the intercooler coolant flowing through the thermal management coupler, and generate the real-time adjusted flow rate.
[0061] In a preferred embodiment, generating the real-time adjusted flow rate includes: sending a flow rate adjustment command to the driver of a three-way regulating valve to drive the three-way regulating valve to adjust the valve opening, wherein the three-way regulating valve corresponds to the main coolant pump, the intercooler coolant inlet of the thermal management coupler, and the bypass circuit.
[0062] The adjustment of the valve opening essentially changes the flow distribution ratio between the thermal management coupler and the bypass circuit.
[0063] The change in the flow allocation ratio results in the flow rate being adjusted in real time.
[0064] Specifically, the step of executing the flow regulation command to generate the real-time regulated flow rate in this invention is the physical realization of the upper-level control intent. This process begins with the flow regulation command output by the controller. This command is sent to the actuator of the three-way control valve. The actuator, typically an electronically controlled actuator such as a stepper motor or DC motor, receives and parses the flow regulation command, the amplitude or duty cycle of which corresponds to a specific target valve opening. The actuator then drives the valve core or baffle inside the three-way control valve to perform precise angular or linear displacement, thereby dynamically adjusting the flow path connectivity and flow cross-sectional area between its three ports.
[0065] One inlet of the three-way regulating valve connects to the output of the main coolant pump, one outlet connects to the intercooler coolant inlet of the thermal management coupler, and the other outlet connects to a bypass loop that directly returns to the main circulation. The main coolant pump output is the water flow from the main water pipe, providing a constant or variable total flow input to the three-way regulating valve. Upon receiving this total flow, the three-way regulating valve distributes it to two downstream branches according to control commands: one branch leads to the intercooler coolant inlet of the thermal management coupler, a critical path for energy recovery and redistribution; the incoming water is heated, and the flow rate through this inlet directly determines the heat exchange power. The other branch leads to the bypass loop, used for stepless flow regulation and stable system operation; the incoming water temperature remains constant, ensuring that regardless of the three-way regulating valve's adjustment, the total output flow of the main coolant pump has a smooth circulation path.
[0066] Adjusting the valve opening essentially acts as a flow distributor, altering the ratio of flow to the thermal management coupler to flow to the bypass loop. When increased heat exchange is required (i.e., the command value increases), the valve opening increases, directing more coolant to the thermal management coupler; conversely, the flow rate decreases, with the excess flowing away through the bypass loop.
[0067] The real-time changes in the distribution ratio directly lead to a dynamic adjustment of the intercooler coolant flow rate that ultimately flows into the thermal management coupler. The stable flow rate formed after this adjustment is the real-time adjusted flow rate. To ensure a precise closed loop in the entire execution process, a flow sensor installed at the inlet of the thermal management coupler continuously monitors this real-time adjusted flow rate and provides it as the actual flow rate feedback value to the PID controller in the previous stage, forming a continuous verification and correction cycle.
[0068] This method, through precise control of the three-way regulating valve, transforms the abstract digital commands output by the upper-level control system into precise and dynamic physical manipulation of fluid flow in the physical world, forming a crucial bridge from intelligent decision-making to physical execution. This step endows the entire thermal management system with high dynamic response capabilities, enabling it to quickly respond to changes in control commands and follow the changes in the optimal heat exchange demand sequence of the thermal management coupler. This ensures that the heat exchange volume closely matches the optimal setting even when engine operating conditions change rapidly. This high-fidelity execution capability is the physical basis for realizing the synergistic cooling strategy, guaranteeing that the theoretical performance gains from prediction and optimization can be applied losslessly to the actual thermal management process, thereby ensuring the high efficiency and stability of the entire system.
[0069] S6. Within the thermal management coupler, the engine high-temperature coolant is guided to flow through its first flow channel, and the intercooler coolant with real-time adjustable flow rate is guided to flow through its second flow channel for heat exchange to output pre-cooled high-temperature coolant and pre-heated intercooler coolant.
[0070] In a preferred embodiment, the heat exchange to output pre-cooled high-temperature coolant and pre-heated intercooler coolant includes: within a thermal management coupler, allowing the engine high-temperature coolant to undergo counter-current heat exchange with the intercooler coolant, which has a real-time adjustable flow rate.
[0071] Through counter-current heat exchange, some of the heat from the engine's high-temperature coolant is transferred to the intercooler coolant.
[0072] The output is pre-cooled high-temperature coolant with a reduced temperature and preheated intercooler coolant with a increased temperature.
[0073] Specifically, the step of performing heat exchange within the thermal management coupler to output two regulated coolants in this invention is the core physical process of energy scheduling and redistribution.
[0074] The thermal management coupler is a high-efficiency plate or microchannel heat exchanger with an internally designed system of isolated but tightly fitted flow channels. In this step, the high-temperature engine coolant from the engine's high-temperature cooling circuit is guided and forced to flow through the first flow channel of the thermal management coupler, i.e., the hot side. Simultaneously, the intercooler coolant, with its flow rate precisely controlled in real-time by the previous step, is guided and forced to flow through the second flow channel of the thermal management coupler, i.e., the cold side. These two flow channels are physically completely isolated, ensuring that the two coolants do not mix. The channel walls are made of a high thermal conductivity metal material, forming a highly efficient heat exchange interface. To maximize heat exchange efficiency, the flow directions of the two fluids are preferably designed as counter-current or cross-counter-current arrangements. When the high-temperature engine coolant and the low-temperature intercooler coolant flow in parallel within this heat exchanger, according to the second law of thermodynamics, heat will spontaneously transfer from the high-temperature engine coolant in the first flow channel, through the heat-conducting wall, to the intercooler coolant in the second flow channel.
[0075] The exchange power of this heat exchange process Determined by the following formula ,in, It is the actual heat exchange power, the value of which is controlled by the real-time adjusted flow rate to approximate the current value of the optimal heat management coupler heat exchange demand sequence; The overall heat transfer coefficient characterizes the rate of heat transfer per unit temperature difference and unit area. It includes various heat transfer resistances such as the convective heat transfer coefficient on the fluid side, the thermal conductivity of the pipe wall, and potential fouling thermal resistance. For example, under typical operating conditions, the overall heat transfer coefficient measured through fluid dynamics simulation or experimental calibration is 2500 W / (m²). 2 ·K); This refers to the total effective heat exchange area, which is the sum of the contact areas where heat exchange occurs between two fluids. It is an inherent design parameter of the thermal management coupler. For example, if the thermal management coupler uses a high-efficiency plate structure, the total effective heat exchange area is set to 1.6m². 2 The area design is intended to ensure that the expected heat exchange power requirements can be met at the target flow rate and temperature difference; It is the logarithmic mean temperature difference, used to quantify the effective average value of the temperature difference that changes continuously due to heat exchange along the entire length of the heat exchanger. Its calculation formula is: ,in and These refer to the temperature difference between the high-temperature fluid and the low-temperature fluid at the inlet and outlet of the heat exchanger, respectively, which is measured by temperature sensors installed at the inlet or outlet of the coupler.
[0076] Through this heat transfer process, the engine high-temperature coolant flowing out of the first flow channel loses heat and its temperature decreases, becoming pre-cooled high-temperature coolant; at the same time, the intercooler coolant flowing out of the second flow channel absorbs heat and its temperature increases, becoming pre-heated intercooler coolant.
[0077] This method couples the thermal energy of two independent cooling systems through a core component: a thermal management coupler. It no longer treats the engine cooling system and intercooler cooling system as isolated units, but rather creates a platform for internal energy circulation and redistribution. The direct effects of this step are twofold: First, it utilizes the lower temperature of the intercooler coolant to pre-treat the high-temperature coolant entering the EGR cooler, reducing its thermal potential energy and creating more favorable conditions for subsequent deep cooling of the EGR exhaust gas, thereby enhancing emission control potential. Second, it transfers the "waste heat" recovered from the engine cooling system to the intercooler coolant, transforming it from a purely cooling medium into a precisely controllable heating medium, providing a heat source for subsequent precise control of the boost intake air temperature. This design transforms potentially conflicting thermal management requirements into a mutually reinforcing synergistic relationship, forming the physical basis for optimizing the overall system energy efficiency.
[0078] S7. The pre-cooled high-temperature coolant is delivered to the EGR cooler for deep cooling of the EGR exhaust gas.
[0079] In a preferred embodiment, the step of conveying the pre-cooled high-temperature coolant to the EGR cooler for deep cooling of the EGR exhaust gas includes: introducing the pre-cooled high-temperature coolant into the coolant channel of the EGR cooler.
[0080] Inside the EGR cooler, the pre-cooled high-temperature coolant exchanges heat with the high-temperature EGR exhaust gas to generate cooled EGR exhaust gas.
[0081] The cooled EGR exhaust gas is sent into the engine's intake manifold.
[0082] Specifically, the step of using pre-cooled high-temperature coolant to cool EGR exhaust gas in this invention is a key application of utilizing the energy dispatching results from the previous stage to achieve emission control targets. This process begins with pre-cooled high-temperature coolant flowing from the outlet of the first flow channel of the thermal management coupler. This coolant is directly transported to the coolant inlet of the EGR cooler via a dedicated pipeline. The EGR cooler is typically a compact shell-and-tube or plate-fin heat exchanger designed for efficient operation under extremely high temperature differences.
[0083] Inside the EGR cooler, pre-cooled high-temperature coolant circulates within its dedicated coolant channels. Simultaneously, a portion of the high-temperature EGR exhaust gas, diverted from the engine exhaust manifold through the EGR valve, is introduced into the EGR cooler's exhaust gas channels. These two channels are isolated but have a large contact surface area to facilitate heat transfer. Because the incoming pre-cooled high-temperature coolant is already significantly cooler than the engine's main cooling cycle temperature, a substantial temperature difference is created between it and the EGR exhaust gas, which reaches hundreds of degrees Celsius. This increased temperature difference greatly enhances the driving force of the heat exchange process, allowing heat from the EGR exhaust gas to be rapidly and extensively transferred to the pre-cooled high-temperature coolant, thus achieving deep cooling of the EGR exhaust gas.
[0084] After heat exchange is completed, the cooled EGR exhaust gas, whose temperature has been significantly reduced, flows out from the outlet of the EGR cooler and is precisely sent into the engine intake system through pipelines, where it mixes with the boosted air after the throttle valve.
[0085] This method directly optimizes engine emissions performance by dedicating pretreated coolant to EGR cooling. Its core technological advantage lies in achieving deep cooling of the EGR exhaust gas. Because the EGR exhaust gas entering the cylinder is at a lower temperature, it more effectively reduces the peak combustion temperature within the combustion chamber, a fundamental way to suppress nitrogen oxide (NOx) formation. Therefore, this step directly translates the optimized energy scheduling within the thermal management system into a substantial reduction in engine emissions. This approach not only improves the efficiency of the EGR system but also demonstrates the value of the co-design in this invention. The pre-cooling function of the thermal management coupler in the previous step provides a prerequisite for the deep cooling effect in this step, enabling the overall system's emission control capability to surpass the simple summation of individual components operating independently.
[0086] S8. Introduce preheated intercooler coolant into the intercooler cooling circuit to regulate the boost intake air temperature.
[0087] In a preferred embodiment, the step of introducing preheated intercooler coolant into the intercooler cooling circuit to regulate the boost intake air temperature includes: mixing the preheated intercooler coolant with the main coolant in the intercooler cooling circuit to form a mixed coolant.
[0088] The mixed coolant is sent to the intercooler to exchange heat with the high-temperature boosted intake air, generating regulated boosted intake air.
[0089] The adjusted boosted air is sent into the engine cylinders.
[0090] Specifically, the step of introducing preheated intercooler coolant into the intercooler cooling circuit to regulate the boosted intake air temperature is a key step in improving engine combustion efficiency by utilizing recovered energy. This process begins with preheated intercooler coolant flowing from the outlet of the second flow channel of the thermal management coupler. This coolant is guided through pipes to a mixing point in the intercooler cooling circuit, where it merges and mixes with the main circuit coolant from the low-temperature radiator, forming a mixed coolant with a precisely raised temperature.
[0091] The mixed coolant is then pumped to the intercooler, also known as the turbocharged air cooler, which is essentially a gas-liquid heat exchanger. The mixed coolant flows through its internal liquid-cooled channels, while the high-temperature, high-pressure intake air from the turbocharger flows through its external air channels. Here, heat is transferred from the intake air to the mixed coolant. Because the temperature of the mixed coolant is controlled, the temperature of the intake air is not only reduced but also precisely adjusted to a preset target range to achieve optimal intake air density and temperature.
[0092] After heat exchange is completed, the appropriately regulated pressurized intake air is directly delivered to the intake valves of each cylinder of the engine through the intake pipe to participate in the subsequent combustion process.
[0093] This method utilizes recovered heat energy to actively heat the intercooler coolant, achieving precise, bidirectional regulation of the boosted intake air temperature and overcoming the limitation of traditional intercooler systems that can only passively cool. This precise temperature control allows the engine control unit to provide the engine with optimal intake air temperature under different operating conditions. While ensuring sufficient intake air density, it avoids problems such as poor fuel atomization and reduced combustion efficiency caused by excessively low intake air temperature, thus achieving an optimal balance between intake air density and combustion efficiency. This step, combined with the synergistic cooling of the EGR system, forms a synergistic regulation, translating the energy optimization results—heat recovery—into direct benefits for engine performance improvement, enhancing fuel economy and power responsiveness across the entire operating range.
[0094] It should be noted that the formulas described above, through the principle of dimensional consistency and mathematical standardization methods (such as normalization, dimensionless parameter conversion, or unit system unification), can translate physical quantities with different properties into unitless standard values or superimposed parameters of the same dimension. This eliminates the interference of different dimensions on the computational logic, allowing the formulas to retain the original data distribution characteristics while possessing mathematical rationality and adaptability to objective laws. The descriptions are merely exemplary embodiments of the present invention and should not be construed as limiting the scope of the invention.
Claims
1. A method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system, characterized in that, include: S1. Acquire engine operating parameters, vehicle operating status parameters and external environment parameters, and merge them into a real-time status data stream; S2. Input the real-time status data stream into the multi-objective predictive control model used to predict the future operating trend of the engine, and generate prediction results including future heat load, emission generation trend and fuel consumption rate. S3. Based on the prediction results, the optimal thermal management coupler heat exchange demand sequence in the prediction time domain is calculated using a function that minimizes the overall performance. S4. Extract the current value from the heat exchange demand sequence of the preferred thermal management coupler, and generate a flow regulation command based on the current value; S5. Execute the flow regulation command to control the three-way regulating valve, dynamically adjust the flow rate of the intercooler coolant flowing through the thermal management coupler, and generate the real-time adjusted flow rate. S6. In the thermal management coupler, the engine high-temperature coolant is guided to flow through its first flow channel, and the intercooler coolant with real-time flow regulation is guided to flow through its second flow channel to exchange heat and output pre-cooled high-temperature coolant and pre-heated intercooler coolant. S7. The pre-cooled high-temperature coolant is delivered to the EGR cooler for deep cooling of the EGR exhaust gas; S8. Introduce preheated intercooler coolant into the intercooler cooling circuit to regulate the boost intake air temperature.
2. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The acquisition of engine operating parameters, vehicle operating status parameters, and external environmental parameters, and their fusion into a real-time status data stream, includes: Engine speed parameters, load parameters, and temperature parameters are collected by a sensor array to form engine operating condition parameters; The vehicle's operating status parameters are obtained via the vehicle bus, including current vehicle speed parameters, vehicle load parameters, and the driver's acceleration or deceleration intentions. External environmental parameters are obtained by using external environmental sensors to acquire ambient temperature and humidity parameters, which constitute the external environmental parameters. The engine operating parameters, vehicle operating status parameters, and external environmental parameters are timestamped and integrated into a real-time status data stream.
3. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The step of inputting real-time status data streams into a multi-objective predictive control model for predicting future engine operating trends, and generating prediction results including future heat load, emission generation trends, and fuel consumption rates, includes: Using real-time status data stream as input, the heat load prediction sub-model integrated within the multi-objective predictive control model is used to identify and quantify the future heat load variation trend of the engine. The generated future heat load change trend, together with the original real-time status data stream, is used as input to the emission and fuel consumption prediction sub-model inside the multi-objective predictive control model to determine the emission generation trend and fuel consumption rate. Based on the real-time status data stream, the current operating mode of the engine is determined by a preset operating condition identifier. The operating modes include economic cruise mode, power climbing mode, or cold start warm-up mode. Based on the engine's current operating mode, a set of corresponding dynamic weight vectors is retrieved from a preset weight lookup table; The predicted trends in heat load, emissions generation, and fuel consumption rate, along with this set of dynamic weight vectors, constitute the final output prediction result.
4. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The calculation of the optimal thermal management coupler heat exchange demand sequence in the prediction time domain includes: Based on the predicted future heat load, emission generation trends and fuel consumption rate, a comprehensive performance objective function is constructed. Within the rolling time window, the comprehensive performance objective function is solved using an algorithm for solving constrained optimization problems, generating a preferred thermal management coupler heat exchange demand sequence. In each control cycle, the optimal thermal management coupler heat exchange demand sequence is updated using the latest forecast results.
5. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The step of extracting the current value from the heat exchange demand sequence of the preferred thermal management coupler and generating a flow regulation command based on the current value includes: The current value of the optimal thermal management coupler heat exchange demand sequence is converted into a flow rate setpoint. The actual flow rate feedback value through the thermal management coupler is obtained using a flow sensor; The flow setpoint and actual flow feedback value are input to the controller used for closed-loop control, which calculates and outputs flow regulation commands.
6. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The generation of the real-time adjusted flow rate includes: The flow regulation command is sent to the driver of the three-way regulating valve to drive the three-way regulating valve to adjust the valve opening. The three-way regulating valve corresponds to the main coolant pump, the intercooler coolant inlet of the thermal management coupler, and the bypass circuit, respectively. The adjustment of the valve opening essentially changes the flow distribution ratio between the thermal management coupler and the bypass circuit. The change in the flow allocation ratio results in the flow rate being adjusted in real time.
7. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The process of heat exchange to output pre-cooled high-temperature coolant and pre-heated intercooler coolant includes: Within the thermal management coupler, the engine's high-temperature coolant and the intercooler coolant with real-time adjustable flow rate undergo counter-current heat exchange. Through counter-current heat exchange, a portion of the heat from the engine's high-temperature coolant is transferred to the intercooler coolant. The output is pre-cooled high-temperature coolant with a reduced temperature and preheated intercooler coolant with a increased temperature.
8. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The step of conveying the pre-cooled high-temperature coolant to the EGR cooler for deep cooling of the EGR exhaust gas includes: Pre-cooled high-temperature coolant is introduced into the coolant flow channel of the EGR cooler; Inside the EGR cooler, the pre-cooled high-temperature coolant exchanges heat with the high-temperature EGR exhaust gas to generate cooled EGR exhaust gas. The cooled EGR exhaust gas is sent into the engine's intake manifold.
9. The method for optimizing the synergistic cooling efficiency of an intercooler and an EGR system according to claim 1, characterized in that, The step of introducing preheated intercooler coolant into the intercooler cooling circuit to regulate the boost intake air temperature includes: The preheated intercooler coolant is mixed with the main coolant in the intercooler cooling circuit to form a mixed coolant; The mixed coolant is sent to the intercooler to exchange heat with the high-temperature boosted intake air, generating regulated boosted intake air; the regulated boosted intake air is then sent to the engine cylinders.