Integrated multi-mode control heat transfer process experiment system and method

Abstract

The invention discloses an integrated multi-mode control heat transfer process experiment system and method, relates to the technical field of thermotechnical experiment equipment, and aims at solving the technical problems that traditional heat transfer experiment equipment is low in data integration level, single in control mode and poor in compatibility. According to the invention, the management system module, the electrical control module and the data acquisition and display module are integrated, a unified data management platform is established, and the problems of data dispersion and low integration level of traditional equipment are thoroughly solved. All the modules are linked through standard interfaces, parameters such as temperature and flow can be collected in real time, continuously stored, played back in a curve and exported in a general format, data recording and sorting in the whole experiment process can be completed without manual intervention, the integrity and processing efficiency of experiment data are greatly improved, and the experiment efficiency is improved. The problems that traditional heat transfer experimental equipment is low in data integration level, single in control mode and poor in compatibility are solved.

Description

Technical Field

[0001] This invention relates to the field of thermal experimental equipment technology, and more specifically, to an integrated multi-mode controlled heat transfer process experimental system and method. Background Technology

[0002] In thermal engineering experimental teaching and research activities, heat transfer process experimental equipment is a core tool for exploring the laws of heat transfer, verifying heat transfer theories, and carrying out related technological research and development. Its performance directly affects the quality of experimental teaching and the reliability of research results. With the continuous development of education and the continuous improvement of scientific research level, traditional heat transfer process experimental equipment has gradually exposed many technical shortcomings that cannot be ignored, and can no longer meet the current diversified, high-precision, and highly flexible experimental needs.

[0003] Traditional heat transfer experimental equipment mostly supports only manual control or a single, fixed automatic control mode. In manual control mode, the adjustment of experimental parameters relies entirely on the operator's experience, which is not only labor-intensive but also prone to poor data repeatability due to human error, making it difficult to meet the requirements of standardized experiments in basic teaching. On the other hand, a single automatic control mode can only achieve simple parameter adjustment for specific operating conditions, failing to adapt to different scenarios such as principle demonstrations in basic teaching, maintaining stable parameters in standardized experiments, and simulating complex dynamic operating conditions in scientific research. In particular, it cannot meet the verification needs of custom control logic and advanced control algorithms in scientific research, greatly limiting the application scope of the equipment. Furthermore, the lack of coordination in signal transmission between modules leads to delayed data updates, requiring manual recording or extraction from multiple independent devices, which is not only cumbersome but also prone to data loss and error accumulation, making real-time monitoring and dynamic adjustment of the experimental process difficult, seriously affecting the integrity and traceability of experimental data. Therefore, we propose an integrated multi-mode control experimental system and method for heat transfer processes. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art, adapt to practical needs, and provide an integrated multi-mode control experimental system and method for heat transfer processes, so as to solve the technical problems of low data integration, single control mode, and poor compatibility of current traditional heat transfer experimental equipment.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an integrated multi-mode control heat transfer process experimental system, the system comprising a piping module and an electrical control module. The piping module consists of hot-side piping, cold-side piping, and a shell-and-tube heat exchanger connecting the hot-side and cold-side piping, used to form and execute the heat transfer process of cold and hot media. The electrical control module is connected to the piping module and includes a core PLC controller and a frequency converter. The core PLC controller is configured to support three control modes: manual control mode, automatic control mode, and external control mode. The frequency converter is used to adjust the water pump flow rate in the cold-side and / or hot-side piping. The electrical control module is equipped with an open communication interface. In the external control mode, the core PLC controller can receive custom control commands sent from an external computer program through this interface and drive the frequency converter to realize a custom control algorithm for flow rate.

[0006] Preferably, the hot-side piping includes a hot medium tank, a hot-side water pump, a hot-side regulating valve, and connecting pipes. The hot-side water pump drives the hot medium to flow through the hot-side piping and through the hot-side channel of the shell-and-tube heat exchanger. The cold-side piping includes a cold medium tank, a cold-side water pump, a cold-side regulating valve, and connecting pipes. The cold-side water pump drives the cold medium to flow through the cold-side piping and through the cold-side channel of the shell-and-tube heat exchanger. Both the hot-side and cold-side piping are equipped with temperature sensors and flow sensors to measure the temperature and flow parameters of the fluid. , , , , ,and ; in, This refers to the inlet temperature on the hot side. This refers to the hot-side outlet temperature. This refers to the volumetric flow rate on the hot side. This refers to the cold-side inlet temperature. This refers to the cold side outlet temperature. This represents the cold-side volumetric flow rate.

[0007] Preferably, in the automatic control mode, the core PLC controller executes a PID control algorithm: based on the deviation... Calculate control quantity ; in For setting value, This refers to the hot-side outlet temperature. It is proportional gain. It is integral gain. It is the differential gain.

[0008] Preferably, in the external control mode, the host computer operates at a fixed cycle. All sensor data is read from the core PLC controller and denoted as vectors. Run custom control algorithms Generate control commands Such as cold side flow rate setpoint ,Right now ; in, This refers to the inlet temperature on the hot side. This refers to the hot-side outlet temperature. This refers to the volumetric flow rate on the hot side. This refers to the cold-side inlet temperature. This refers to the cold side outlet temperature. This represents the cold-side volumetric flow rate.

[0009] Preferably, the electrical control module also integrates intelligent instruments to receive signals from temperature sensors and flow sensors on the cold and hot sides of the piping module, perform preliminary processing, and then transmit the data to the core PLC controller.

[0010] Preferably, the open communication interface is an RS485 interface that supports the Modbus-RTU protocol and is used to communicate with the data acquisition and display module and the host computer.

[0011] Preferably, the hot medium tank is an insulated water tank with heating function, the cold medium tank is a cold water tank, and both the cold medium and the hot medium are tap water.

[0012] Preferably, it also includes a data acquisition and display module, which is communicatively connected to the electrical control module and is used to acquire, display, record and export the operating parameters of the piping system module in real time, and provide a human-machine interface; The data acquisition and display module integrates a data storage unit and a touch screen human-machine interface; The data storage unit can store the operating parameters in the internal memory or external storage device at set time intervals, and supports historical data query and curve playback; The touch screen human-machine interface is connected to the core PLC controller, and displays the parameters measured by the temperature sensors and flow sensors on the cold side and hot side of the piping module in real time, and dynamically displays the system operation status in the form of a flowchart.

[0013] An experimental method for an integrated multi-mode controlled heat transfer process, comprising the following steps: S100, System Preparation and Initialization: First, prepare the experimental system by adding sufficient tap water to the hot and cold medium tanks as heat transfer media. Then, connect the main power supply to the system and start the electrical control modules such as the core PLC controller and the touch screen human-machine interface. The system will perform a self-test. The operator needs to confirm on the touch screen that all temperature and flow sensor signals are normal to ensure that there are no leaks in the piping modules and to establish a stable foundation for subsequent experiments. S200. Experimental Objective Setting and Mode Selection: After the system initialization is completed, set the experimental objectives according to the specific purpose of the experiment. Select the corresponding control mode on the touch screen according to the complexity requirements of the experiment. The manual mode is suitable for basic teaching, the automatic mode is suitable for standardized experiments, and the external control mode provides a platform for advanced algorithm research. S300, Experiment Execution and Process Control: The corresponding control strategy is executed according to the selected control mode. In manual mode, the user can directly adjust the water pump frequency and heater power through the touch screen. In automatic mode, the system runs the built-in PID algorithm to maintain parameter stability. In external control mode, the system connects to the host computer through the RS485 interface to run a custom control algorithm to realize advanced control strategies. S400, Data Logging and Monitoring: During the experiment, the system automatically collects and records key parameters such as temperature and flow rate. The data storage unit stores the operating data at set time intervals. Operators can monitor the system status and observe parameter curves in real time through the touch screen, and promptly detect and handle alarm information to ensure the safety and reliability of the experiment. S500, Data Processing and Analysis: After the experimental phase is completed, the recorded historical data will be exported in a common file format, and professional software will be used for data processing and analysis. By calculating the heat transfer coefficient and plotting performance curves, the experimental effect will be evaluated, the effectiveness of the control strategy will be verified, and the experimental report will be written. S600 System Shutdown and Maintenance: After the experiment is completed, shut down the system in the standard sequence: first stop the heater, then turn off the water pump, and disconnect the main power supply after the system has cooled down. If necessary, clean the pipelines and maintain the equipment. Regularly check the accuracy of the sensors to ensure long-term stable operation of the equipment.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention integrates the piping system module, electrical control module, and data acquisition and display module into a unified data management platform, completely solving the problems of scattered data and low integration in traditional equipment. Each module operates through standardized interfaces, enabling real-time acquisition, continuous storage, curve playback, and export of parameters such as temperature and flow rate in universal formats. The intelligent design of the data acquisition and display module allows for data recording and processing throughout the entire experimental process without manual intervention, significantly improving the integrity, traceability, and processing efficiency of experimental data. This addresses the issues of low data integration, single control mode, and poor compatibility in traditional heat transfer experimental equipment.

[0015] 2. This invention also integrates three control modes—manual, automatic, and external—to perfectly cover different experimental scenarios. The manual control mode simplifies the principle demonstration and equipment debugging process in basic teaching; the automatic control mode embeds a PID control algorithm, which can automatically correct parameter deviations, maintain experimental parameter stability, and ensure the repeatability and accuracy of data in standardized experiments; the external control mode supports receiving custom control commands from the host computer through a standardized interface, and is compatible with the verification and application of advanced control algorithms such as fuzzy adaptive PID, providing a flexible experimental platform for the study of complex dynamic heat transfer processes and the exploration of new control strategies in scientific research. Attached Figure Description

[0016] Figure 1 This is a system block diagram of the present invention; Figure 2 This is a flowchart of the method of the present invention. Detailed Implementation

[0017] Example 1: like Figure 1 As shown, this embodiment provides an integrated multi-mode control heat transfer process experimental system. The system includes a piping module and an electrical control module, as well as a data acquisition and display module. The data acquisition and display module is communicatively connected to the electrical control module and is used to acquire, display, record and export the operating parameters of the piping module in real time, and provide a human-machine interface. The data acquisition and display module integrates a data storage unit and a touch screen human-machine interface. The piping module consists of hot-side piping, cold-side piping, and a shell-and-tube heat exchanger connecting the hot-side and cold-side piping. It is used to form and execute the heat transfer process between the hot and cold media. The hot-side piping includes a hot medium tank, a hot-side water pump, a hot-side regulating valve, and connecting pipes. The hot-side water pump drives the hot medium to flow through the hot-side piping and through the hot-side channel of the shell-and-tube heat exchanger. The hot medium tank is an insulated water tank with heating function. The cold-side piping includes a cold medium tank, a cold-side water pump, a cold-side regulating valve, and connecting pipes. The cold-side water pump drives the cold medium to flow through the cold-side piping and through the cold-side channel of the shell-and-tube heat exchanger. Temperature sensors and flow sensors are installed on both the hot-side and cold-side piping to measure the temperature and flow parameters of the fluid. The cold medium tank is a cold water tank. Both the cold and hot media are tap water.

[0018] The hot-side inlet temperature is denoted as The hot-side outlet temperature is recorded as The hot-side volumetric flow rate is denoted as ; The cold side inlet temperature is denoted as The cold side outlet temperature is recorded as The cold side volumetric flow rate is denoted as ; All sensor signals , , , , ,and It is connected to the core PLC controller.

[0019] The electrical control module is connected to the piping system module. The electrical control module includes a core PLC controller and a frequency converter. The core PLC controller is a Schneider Modicon M200 series PLC, configured to support three control modes: manual control, automatic control, and external control. The frequency converter is a Kewo CHV100 series frequency converter, controlling the cold-side and hot-side water pumps respectively. The core PLC controller sends speed control signals to the frequency converter. Precisely control the flow rate of the medium and It is used to regulate the flow rate of water pumps in cold-side and / or hot-side piping.

[0020] The electrical control module is equipped with an open communication interface, which is an RS485 interface using the Modbus-RTU protocol. It is used to communicate with the data acquisition and display module and exchange data with the host computer software in external control mode.

[0021] In external control mode, the core PLC controller can receive custom control commands from an external computer program through this interface and drive the frequency converter to implement a custom flow control algorithm. The electrical control module also integrates intelligent instruments, using the Yudian AI-708 series intelligent instruments. These instruments receive signals from temperature and flow sensors on the cold and hot side pipes in the piping module, perform preliminary processing, and then transmit the data to the core PLC controller. The electric heater in the hot water tank is controlled by the core PLC controller to start and stop; its on / off status is recorded as follows. , where 1 means on and 0 means off.

[0022] a. Manual control mode: mainly used for system debugging, equipment maintenance or basic teaching demonstrations.

[0023] When the user selects manual mode on the touchscreen, the core PLC controller completely hands over control to the user. The user can directly set the output control signals of the cold and hot side inverters via the virtual slider on the touchscreen. and The heater's on / off state can be controlled directly by clicking the button. The core PLC controller only serves as a channel for instruction transmission and signal acquisition; it does not execute any automatic control algorithms. All parameter changes and experimental phenomena are observed and recorded by the user.

[0024] b. Automatic control mode: Suitable for standardized teaching experiments, such as heat transfer coefficient measurement and the effect of flow rate on heat transfer effect.

[0025] The user selects the automatic mode and sets the control target, such as maintaining the hot side outlet temperature. Constant at the set value The core PLC controller executes an internally preset PID control program, the specific algorithm of which is described below: Calculate deviation: Read the current Actual value, calculated value and set value deviation ,Right now:

[0026] PID calculation: based on deviation The PID algorithm is used to calculate the control quantity that should be output to the actuator, such as the hot-side frequency converter. ,Right now:

[0027] in, It is proportional gain. It is integral gain. It is the differential gain; all three parameters were tuned during the system debugging phase. Output control: The calculated... Converted to standard control signals Output to the frequency converter to adjust the hot-side flow. ,make Gradually approaching and stabilizing at .

[0028] c. External control mode: Suitable for scientific research experiments, used to verify advanced control algorithms or study dynamic heat transfer processes.

[0029] The user selects the external control mode; a host computer connects to the communication port of the core PLC controller via an RS485 to USB cable. The host computer runs a user-defined control program, such as one developed using MATLAB / Simulink, Python, or LabVIEW. The core PLC controller and the host computer communicate using the Modbus-RTU protocol, and the host computer program executes at a fixed interval. ,like All sensor data is read from the core PLC controller and denoted as vectors. :

[0030] The host computer program uses real-time data Run custom control algorithms Calculate the control command that should be applied at the current time. For example, including cold side flow rate setpoint ,Right now ; The host computer will send control commands The message is sent to the core PLC controller. After receiving it, the core PLC controller no longer uses the internal PID algorithm but directly executes the host computer instructions to drive the corresponding frequency converter or actuator.

[0031] Algorithm Example (Fuzzy Adaptive PID): Advanced algorithms can be verified in external mode, including those from the host computer. The PID parameters can be adjusted in real time according to the system status, for example, by defining fuzzy rules and adjusting them based on the deviation. and rate of change of deviation Dynamic correction , ,and Generate adaptive parameters , ,and This achieves better control performance than fixed-parameter PID control.

[0032] The data storage unit can store operating parameters in internal or external storage devices at set time intervals, and supports historical data query and curve playback. The touch screen HMI is connected to the core PLC controller. The touch screen HMI uses a Kunlun Tongtai TPC7062Ti touch screen, which communicates with the core PLC controller via an RS485 port. It displays the parameters measured by temperature and flow sensors on the cold and hot side pipes in the piping module in real time, and dynamically displays the system operating status in the form of a flowchart. After the experiment, the exported CSV data file is imported into professional software (such as Origin, Excel) for processing, calculating performance indicators such as the heat transfer coefficient K, and plotting its variation with time. A changing curve.

[0033] Example 2: like Figure 2 As shown, this embodiment provides an experimental method for integrated multi-mode control of a heat transfer process, which includes the following steps: S100, System Preparation and Initialization: First, prepare the experimental system by adding sufficient tap water to the hot and cold medium tanks as heat transfer media. Then, connect the main power supply to the system and start the electrical control modules such as the core PLC controller and the touch screen human-machine interface. The system will perform a self-test. The operator needs to confirm on the touch screen that all temperature and flow sensor signals are normal to ensure that there are no leaks in the piping modules and to establish a stable foundation for subsequent experiments. S200. Experimental Objective Setting and Mode Selection: After the system initialization is completed, set the experimental objectives according to the specific purpose of the experiment. Select the corresponding control mode on the touch screen according to the complexity requirements of the experiment. The manual mode is suitable for basic teaching, the automatic mode is suitable for standardized experiments, and the external control mode provides a platform for advanced algorithm research. S300, Experiment Execution and Process Control: The corresponding control strategy is executed according to the selected control mode. In manual mode, the user can directly adjust the water pump frequency and heater power through the touch screen. In automatic mode, the system runs the built-in PID algorithm to maintain parameter stability. In external control mode, the system connects to the host computer through the RS485 interface to run a custom control algorithm to realize advanced control strategies. S400, Data Logging and Monitoring: During the experiment, the system automatically collects and records key parameters such as temperature and flow rate. The data storage unit stores the operating data at set time intervals. Operators can monitor the system status and observe parameter curves in real time through the touch screen, and promptly detect and handle alarm information to ensure the safety and reliability of the experiment. S500, Data Processing and Analysis: After the experimental phase is completed, the recorded historical data will be exported in a common file format, and professional software will be used for data processing and analysis. By calculating the heat transfer coefficient and plotting performance curves, the experimental effect will be evaluated, the effectiveness of the control strategy will be verified, and the experimental report will be written. S600 System Shutdown and Maintenance: After the experiment is completed, shut down the system in the standard sequence: first stop the heater, then turn off the water pump, and disconnect the main power supply after the system has cooled down. If necessary, clean the pipelines and maintain the equipment. Regularly check the accuracy of the sensors to ensure long-term stable operation of the equipment.

[0034] The embodiments disclosed in this invention are preferred embodiments, but are not limited thereto. Those skilled in the art can easily understand the spirit of this invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of this invention, they are all within the protection scope of this invention.

Claims

1. An integrated multi-mode controlled experimental system for heat transfer processes, characterized in that, The system includes a piping module and an electrical control module; The piping module consists of hot-side piping, cold-side piping, and a shell-and-tube heat exchanger connecting the hot-side piping and the cold-side piping, and is used to form and perform the heat transfer process of the cold and hot media. The electrical control module is connected to the piping module, and the electrical control module includes a core PLC controller and a frequency converter; The core PLC controller is configured to support three control modes: manual control mode, automatic control mode and external control mode, and the frequency converter is used to adjust the water pump flow rate in the cold side pipeline and / or hot side pipeline. The electrical control module is equipped with an open communication interface. In the external control mode, the core PLC controller can receive custom control commands sent from an external computer program through this interface and drive the frequency converter to realize a custom control algorithm for flow.

2. The integrated multi-mode controlled heat transfer process experimental system according to claim 1, characterized in that, The hot-side pipeline includes a hot medium tank, a hot-side water pump, a hot-side regulating valve, and connecting pipes. The hot-side water pump drives the hot medium to flow through the hot-side pipeline and through the hot-side channel of the shell-and-tube heat exchanger. The cold-side piping includes a cold medium tank, a cold-side water pump, a cold-side regulating valve, and connecting pipes. The cold-side water pump drives the cold medium to flow through the cold-side piping and through the cold-side channel of the shell-and-tube heat exchanger. Both the hot-side and cold-side piping are equipped with temperature sensors and flow sensors to measure the temperature and flow parameters of the fluid. , , , , ,and ; in, This refers to the inlet temperature on the hot side. This refers to the hot-side outlet temperature. This refers to the volumetric flow rate on the hot side. This refers to the cold-side inlet temperature. This refers to the cold side outlet temperature. This represents the cold-side volumetric flow rate.

3. The integrated multi-mode controlled heat transfer process experimental system according to claim 1, characterized in that, In the automatic control mode, the core PLC controller executes a PID control algorithm: based on the deviation... Calculate control quantity ; in For setting value, This refers to the hot-side outlet temperature. It is proportional gain. It is integral gain. It is the differential gain.

4. The integrated multi-mode controlled heat transfer process experimental system according to claim 1, characterized in that, In the external control mode, the host computer operates at a fixed cycle. All sensor data is read from the core PLC controller and denoted as vectors. Run custom control algorithms Generate control commands Such as cold side flow rate setpoint ,Right now ; in, This refers to the inlet temperature on the hot side. This refers to the hot-side outlet temperature. This refers to the volumetric flow rate on the hot side. This refers to the cold-side inlet temperature. This refers to the cold side outlet temperature. This represents the cold-side volumetric flow rate.

5. The integrated multi-mode controlled heat transfer process experimental system according to claim 2, characterized in that, The electrical control module also integrates intelligent instruments, which receive signals from temperature sensors and flow sensors on the cold and hot sides of the piping module, perform preliminary processing, and then transmit the data to the core PLC controller.

6. The integrated multi-mode controlled heat transfer process experimental system according to claim 1, characterized in that, The open communication interface is an RS485 interface, which supports the Modbus-RTU protocol and is used to communicate with the data acquisition and display module and the host computer.

7. The integrated multi-mode controlled heat transfer process experimental system according to claim 2, characterized in that, The heat medium tank is an insulated water tank with heating function; The cold medium tank is a cold water tank; Both the cold and hot media are tap water.

8. The integrated multi-mode controlled heat transfer process experimental system according to claim 5, characterized in that, It also includes a data acquisition and display module, which is communicatively connected to the electrical control module and is used to acquire, display, record and export the operating parameters of the piping system module in real time, and provide a human-machine interface; The data acquisition and display module integrates a data storage unit and a touch screen human-machine interface; The data storage unit can store the operating parameters in the internal memory or external storage device at set time intervals, and supports historical data query and curve playback; The touch screen human-machine interface is connected to the core PLC controller, and displays the parameters measured by the temperature sensors and flow sensors on the cold side and hot side of the piping module in real time, and dynamically displays the system operation status in the form of a flowchart.

9. An integrated multi-mode controlled heat transfer process experimental method, applicable to the integrated multi-mode controlled heat transfer process experimental system according to any one of claims 1-8, characterized in that, The method includes the following steps: S100, System Preparation and Initialization: First, prepare the experimental system by adding sufficient tap water to the hot and cold medium tanks as heat transfer media. Then, connect the main power supply to the system and start the electrical control modules such as the core PLC controller and the touch screen human-machine interface. The system will perform a self-test. The operator needs to confirm on the touch screen that all temperature and flow sensor signals are normal to ensure that there are no leaks in the piping modules and to establish a stable foundation for subsequent experiments. S200. Experimental Objective Setting and Mode Selection: After the system initialization is complete, set the experimental objectives according to the specific purpose of the experiment. Select the corresponding control mode on the touch screen according to the complexity requirements of the experiment. The manual mode is suitable for basic teaching, the automatic mode is suitable for standardized experiments, and the external control mode provides a platform for advanced algorithm research. S300, Experiment Execution and Process Control: According to the selected control mode, the corresponding control strategy is executed. In manual mode, the user can directly adjust the water pump frequency and heater power through the touch screen. In automatic mode, the system runs the built-in PID algorithm to maintain parameter stability. In external control mode, the system connects to the host computer through the RS485 interface to run a custom control algorithm to realize advanced control strategies. S400, Data Logging and Monitoring: During the experiment, the system automatically collects and records key parameters such as temperature and flow rate. The data storage unit stores the operating data at set time intervals. Operators can monitor the system status and observe parameter curves in real time through the touch screen, and promptly detect and handle alarm information to ensure the safety and reliability of the experiment. S500, Data Processing and Analysis: After the experimental phase is completed, the recorded historical data will be exported in a common file format, and professional software will be used for data processing and analysis. By calculating the heat transfer coefficient and plotting performance curves, the experimental effect will be evaluated, the effectiveness of the control strategy will be verified, and the experimental report will be written. S600 System Shutdown and Maintenance: After the experiment is completed, shut down the system in the standard sequence: first stop the heater, then turn off the water pump, and disconnect the main power supply after the system has cooled down. If necessary, clean the pipelines and maintain the equipment. Regularly check the accuracy of the sensors to ensure long-term stable operation of the equipment.

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