An industrial heat exchange process operation optimization control physical experiment device and method

Abstract

The application provides an industrial heat exchange process operation optimization control physical experiment device and method, and relates to the technical field of automatic control of process industry. The device comprises: a controlled object unit configured to perform operation optimization control experiment; a process control unit configured to detect process parameters of the controlled object in real time, receive a set value instruction from the operation control unit, and adjust a control instruction to realize basic loop control of the controlled object; and an operation control unit configured to read and record industrial heat exchange process data from the process control unit, perform a specific optimization algorithm calculation according to an optimization target required by the experiment, and adjust the set value of the basic loop control of the controlled object to realize optimization of the operation index. The method is based on the experiment device, three basic loop controllers are constructed, the operation index, decision variable and control problem of the operation optimization of the controlled object are defined, and experiment research for realizing optimization of the operation index is performed.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology in process industries, and in particular to a physical experimental apparatus and method for optimizing and controlling the operation of industrial heat exchange processes. Background Technology

[0002] In process industries, using computer control systems such as DCS / PLC to control basic loop variables related to flow rate, temperature, pressure, and liquid level in the production process is a fundamental requirement for achieving automation. Operation optimization control refers to how to optimize the control of operational indicators such as product quality, efficiency, and energy consumption during processing, based on the implementation of basic loop control. In other words, it involves how to adjust the setpoints of the basic control loop of the DCS / PLC control system online according to changes in production boundary conditions and operating conditions to optimize operational indicators.

[0003] Operation optimization control has become a research hotspot in the field of process industry automation in recent years, with a considerable amount of literature conducting theoretical and industrial application research on various operation optimization control algorithms. Due to the inherent dangers in process industries, directly applying advanced control methods to industrial production sites inevitably faces significant risks. Therefore, there is an urgent need for an experimental setup for operation optimization control—a bridge connecting theoretical and industrial applications—to effectively support experimental research on relevant advanced control algorithms and technologies. This allows for the verification of the effectiveness, feasibility, and safety of operation optimization algorithms in a low-risk laboratory environment. Furthermore, operation optimization control is also a cutting-edge technology taught in automation majors; therefore, experimental setups for operation optimization control are also a necessary component of automation technology teaching experiments.

[0004] There are two approaches to conducting operational optimization control experiments in a laboratory environment: simulation experiments based on a model of the controlled object and physical experiments based on real industrial processes. Simulation experiments primarily rely on the mathematical model of the controlled industrial process, including the control layer model and the operation layer model, and the accuracy of the mathematical model directly affects the reliability of the experiment. Most industrial processes in the process industry are characterized by unclear mechanisms, complex influencing factors, and difficulties in modeling; therefore, physical experiments have unique advantages compared to simulation experiments. Currently, only a few documents report on physical experimental devices involving operational optimization control, and the types of specific industrial processes involved are limited. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a physical experimental device and method for optimizing the operation control of industrial heat exchange processes. This invention solves the problem that the existing experimental devices for optimizing the operation control have insufficient variety of physical controlled objects, making it difficult to effectively carry out experiments and teaching of algorithms related to optimizing the operation control, and achieves optimized operation control of the controlled objects.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: On the one hand, the present invention provides a physical experimental device for optimizing and controlling the operation of an industrial heat exchange process, including a controlled object unit, a process control unit, and an operation control unit; The controlled object unit is set as the controlled object for the operation optimization control experiment, including a hot water loop, a cold water loop, and a heat exchange device; the hot water loop provides a heating medium to the heat exchange device through heating, and the heat exchange device exchanges heat with the cold water in the cold water loop through the heat source provided by the hot water loop; during the entire operation of the controlled object, the heated water flow in the hot water loop is regarded as the heating medium used to heat the water flow in the cold water loop, and the water flow in the cold water loop at the cold water outlet of the heat exchange device is regarded as a product that meets the quality requirements; The process control unit detects the process parameters of the controlled object in real time, receives setpoint instructions from the operation control unit, and realizes basic loop control of the temperature and liquid level of the controlled object by adjusting the control instructions. In addition, the process control unit also has the function of starting and stopping the equipment used in the hot water loop and cold water loop. The main body of the operation control unit is an operation control computer, which is connected to the process control unit via a network. The operation control computer executes operation optimization control software, which reads and records industrial heat exchange process data from the process control unit, performs specific optimization algorithm calculations based on the optimization objectives required by the experiment, and adjusts the set values ​​of the basic loop control of temperature and liquid level to achieve optimization of operation indicators.

[0007] Furthermore, the hot water loop includes a water storage tank A, a water pump A, a heating device, and corresponding pipelines. The outlet of the water storage tank A is connected to the input end of the water pump A via a pipeline, and the output end of the water pump A is connected to the top inlet of the heating device via a pipeline. The heating device has both electric heating and water storage functions. An electric heater is installed at the bottom of the heating device to heat the water injected into the heating device via the water pump A. The bottom outlet of the heating device is connected to the hot water inlet of the heat exchange device via a pipeline, and the water flow returns from the hot water outlet of the heat exchange device to the water storage tank A via a pipeline.

[0008] Furthermore, the cold water loop includes a water storage tank B, a water pump B, and corresponding pipelines. The outlet of the water storage tank B is connected to the input end of the water pump B via a pipeline, and the output end of the water pump B is connected to the cold water inlet of the heat exchange device via a pipeline. The water flow returns from the cold water outlet of the heat exchange device to the water storage tank B via a pipeline.

[0009] Furthermore, the heat exchange device has a hot water inlet, a hot water outlet, a cold water inlet, and a cold water outlet. The hot water loop flow and the cold water loop flow exchange heat in the heat exchange device, but no material contact or material exchange occurs.

[0010] Furthermore, the installation position of the heating device should be higher than the installation position of the heat exchange device, and the installation position of the heat exchange device should be higher than the installation positions of the water storage tank A and the water storage tank B, so as to ensure that the hot water loop can flow from the heating device through the heat exchange device back to the water storage tank A by gravity, and the cold water loop can flow from the heat exchange device back to the water storage tank B by gravity.

[0011] Furthermore, the process control unit includes an actuator, a detection instrument, and a process control system; the process control system is used to send control commands to the actuator; the actuator receives control commands from the process control system and drives water pump A, water pump B, and an electric heater; the detection instrument is used to measure online the instantaneous water flow rate of water pump A, water pump B, and the outlet pipeline, the instantaneous liquid level of the water stored in the heating device, the hot water temperature inside the heating device and the cold water outlet temperature of the heat exchange device, as well as the motor power of water pump A, the motor power of water pump B, and the power of the electric heater; the detection instrument connects to the process control system and sends the detected process parameters to the process control system; the process control system receives temperature, flow rate, liquid level, and power signals from the detection instrument, constructs a basic loop controller for temperature and liquid level, and sends corresponding control commands to the actuator so that the controlled variables of each basic loop controller track their set values.

[0012] Furthermore, the actuator includes a frequency converter for water pump A, a frequency converter for water pump B, and a voltage regulating module for an electric heater; the frequency converters for water pump A and water pump B respectively receive frequency commands from the process control system, drive water pump A and water pump B, and convert the frequency commands into the rotational speeds of water pump A and water pump B, thereby regulating the water flow rates of water pump A and water pump B; the voltage regulating module for the electric heater receives heating commands from the process control system, drives the electric heater, and adjusts the heating intensity of the electric heater according to the heating commands.

[0013] Furthermore, the detection instruments include flow meter A, flow meter B, level gauge, thermometer A, thermometer B, power meter for water pump A, power meter for water pump B, and power meter for electric heater. Flow meter A is installed on the outlet pipe of water pump A for online measurement of the instantaneous water flow rate at the outlet pipe of water pump A. Flow meter B is installed on the outlet pipe of water pump B for online measurement of the instantaneous water flow rate at the outlet pipe of water pump B. The level gauge is installed in the heating device for online measurement of the instantaneous water level stored in the heating device. Thermometer A is installed inside the heating device near the bottom outlet for online measurement of the hot water temperature inside the heating device. Thermometer B is installed at the cold water outlet of the heat exchange device for online detection of the cold water outlet temperature of the heat exchange device. The power meters for water pump A, water pump B, and electric heater are respectively connected to the motors of water pump A, water pump B, and electric heater for online measurement of the power of water pump A, water pump B, and electric heater. All detection instruments are connected to the process control system via hard-wired signals or fieldbus signals to send the detected process parameters to the process control system.

[0014] On the other hand, a physical experimental method for optimizing and controlling the operation of an industrial heat exchange process includes the following steps: Step 1: In the process control system, construct three basic loop controllers, including a heating device temperature controller, a heating device liquid level controller, and a heat exchange device cold water outlet temperature controller. The controlled variable of the temperature controller of the heating device is the temperature of the hot water generated inside the heating device as measured by thermometer A, and the control quantity is the heating command of the electric heater pressure regulating module. The controlled variable of the heating device level controller is the water level height in the heating device measured by the level gauge, and the control quantity is the frequency command of the water pump A frequency converter. The controlled variable of the cold water outlet temperature controller of the heat exchange device is the cold water outlet temperature of the heat exchange device measured by thermometer B, and the control quantity is the frequency command of the frequency converter of water pump B. Step 2: Define the operational indicators for optimizing the operation of the controlled object, including energy consumption indicators, output indicators, heating medium consumption indicators, and comprehensive indicators; Among them, the energy consumption index = power of water pump A + power of water pump B + power of electric heater; Production index = Instantaneous flow rate of the outlet pipe of pump B as measured by flow meter B; Heating medium consumption index = instantaneous flow rate of the outlet pipe of pump A measured by flow meter A; The comprehensive indicator is a weighted index of any two or three of the following: energy consumption, heating medium consumption, and output. Step 3: Define the decision variables for optimizing the operation of the controlled object; The decision variables for optimizing the operation of the controlled object include the setpoints of the heating device temperature controller and the heating device liquid level controller. Step 4: Define the optimization control problem for the controlled object; The controlled object operation optimization control problem is defined as follows: Under the premise that the three basic loop controllers constructed in step 1 are put into closed-loop control and meet specific constraints, how to adjust the two decision variables mentioned in step 3 so that the operation index mentioned in step 2 is optimized; Step 5: Start the equipment used in the hot water loop and cold water loop of the controlled object unit through the process control unit, and put the three basic loop controllers into automatic control mode. When the water flow of the controlled object unit enters a steady state, start the operation optimization control software containing a specific optimization algorithm of the operation control unit, and adjust the set values ​​of the heating device temperature controller and heating device liquid level controller online according to the process data of the controlled object unit, and carry out experimental research on optimizing the operation indicators.

[0015] The beneficial effects of adopting the above technical solution are as follows: The physical experimental device and method for optimizing and controlling the operation of an industrial heat exchange process provided by this invention can quantitatively calculate operating indicators, thereby enabling an objective comparison and evaluation of the performance of various operation optimization and control algorithms. This experimental device only requires conventional water as the experimental material for recycling, with no pollution emissions, and the only operating cost is electricity. It does not involve pressure, and the safety of the experiment is well guaranteed. Attached Figure Description

[0016] Figure 1 A schematic diagram of the physical experimental device for operation optimization control based on industrial heat exchange process provided in this embodiment of the invention; Figure 2 The control block diagrams of the three basic loop controllers in the process control system provided in this embodiment of the invention are as follows: (a) is the control block diagram of the temperature controller of the heating device, (b) is the control block diagram of the liquid level controller of the heating device, and (c) is the control block diagram of the cold water outlet temperature controller of the heat exchange device. Detailed Implementation

[0017] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0018] In this embodiment, a physical experimental device for optimizing and controlling the operation of an industrial heat exchange process is described, such as... Figure 1 As shown, it includes the controlled object unit, the process control unit, and the operation control unit; The controlled object unit is set as the controlled object for the operation optimization control experiment, including a hot water loop, a cold water loop and a heat exchange device; the hot water loop provides a heating medium to the heat exchange device through heating, and the heat exchange device exchanges heat with the cold water in the cold water loop through the heat source provided by the hot water loop; In this embodiment, the hot water loop includes a water storage tank A, a water pump A, a heating device, and corresponding pipelines. The outlet of the water storage tank A is connected to the input end of the water pump A via a pipeline, and the output end of the water pump A is connected to the top inlet of the heating device via a pipeline. The heating device has both electric heating and water storage functions. An electric heater is installed at the bottom of the heating device to heat the water injected into the heating device via the water pump A. The bottom outlet of the heating device is connected to the hot water inlet of the heat exchange device via a pipeline, and the water flow returns from the hot water outlet of the heat exchange device to the water storage tank A via a pipeline.

[0019] The cold water loop includes a water storage tank B, a water pump B, and corresponding pipelines. The outlet of the water storage tank B is connected to the input end of the water pump B via a pipeline, and the output end of the water pump B is connected to the cold water inlet of the heat exchange device via a pipeline. The water flow returns from the cold water outlet of the heat exchange device to the water storage tank B via a pipeline.

[0020] The heat exchange device has a hot water inlet, a hot water outlet, a cold water inlet, and a cold water outlet. The hot water loop flow and the cold water loop flow exchange heat in the heat exchange device, but no material contact or material exchange occurs.

[0021] The installation position of the heating device should be higher than the installation position of the heat exchange device, and the installation position of the heat exchange device should be higher than the installation positions of the water storage tank A and the water storage tank B, so as to ensure that the hot water loop can flow from the heating device through the heat exchange device back to the water storage tank A by gravity, and the cold water loop can flow from the heat exchange device back to the water storage tank B by gravity.

[0022] Throughout the operation of the controlled object, the water flow in the hot water loop, heated by the electric heater, is considered as the heating medium used to heat the water flow in the cold water loop, while the water flow in the cold water loop at the cold water outlet of the heat exchanger is considered as a product that meets the quality requirements (reaches the expected temperature). The process control unit detects process parameters such as flow rate, liquid level, temperature and power of the controlled object in real time, receives set value instructions from the operation control unit, and realizes basic loop control of temperature and liquid level of the controlled object by adjusting control instructions (frequency converter frequency instructions and heating instructions). In addition, the process control unit also has the function of starting and stopping equipment used in hot water loop and cold water loop. In this embodiment, the process control unit includes an actuator, a detection instrument, and a process control system. The process control system sends control commands to the actuator. The actuator receives control commands from the process control system and drives water pump A, water pump B, and an electric heater. The detection instrument measures the instantaneous water flow rate of water pump A, water pump B, and the outlet pipeline, the instantaneous liquid level of the water stored in the heating device, the hot water temperature inside the heating device, the cold water outlet temperature of the heat exchange device, and the motor power of water pump A, the motor power of water pump B, and the power of the electric heater. The detection instrument connects to the process control system and sends the detected process parameters to the process control system. The main body of the process control system can be, but is not limited to, a DCS, PLC, or industrial computer. The process control system receives temperature, flow rate, liquid level, and power signals from the detection instrument, constructs a basic loop controller for temperature and liquid level, and sends corresponding control commands to the actuator so that the controlled variables of each basic loop controller track their set values.

[0023] The actuator includes a frequency converter for water pump A, a frequency converter for water pump B, and a voltage regulating module for an electric heater. The frequency converters for water pump A and water pump B respectively receive frequency commands from the process control system, drive water pump A and water pump B, and convert the frequency commands into the rotational speeds of water pump A and water pump B, thereby regulating the water flow rates of water pump A and water pump B. The voltage regulating module for the electric heater receives heating commands from the process control system, drives the electric heater, and adjusts the heating intensity of the electric heater according to the heating commands.

[0024] The detection instruments include flow meter A, flow meter B, level gauge, thermometer A, thermometer B, power meter for water pump A, power meter for water pump B, and power meter for electric heater. Flow meter A is installed on the outlet pipe of water pump A to measure the instantaneous water flow rate of the outlet pipe of water pump A online. Flow meter B is installed on the outlet pipe of water pump B to measure the instantaneous water flow rate of the outlet pipe of water pump B online. The level gauge is installed in the heating device to measure the instantaneous water level stored in the heating device online. The thermometer A is installed inside the heating device near the bottom outlet of the heating device to measure the hot water temperature inside the heating device online. The thermometer B is installed at the cold water outlet of the heat exchange device to detect the cold water outlet temperature of the heat exchange device online. The power meters for water pump A, water pump B, and electric heater are respectively connected to the motors of water pump A, water pump B, and electric heater to measure the power of water pump A, water pump B, and electric heater online. All detection instruments are connected to the process control system via hard-wired signals or fieldbus signals to send the detected process parameters to the process control system.

[0025] The main body of the operation control unit is an operation control computer, which is connected to the process control unit via a network. The operation control computer executes operation optimization control software, which reads and records industrial heat exchange process data from the process control unit, performs specific optimization algorithm calculations based on the optimization objectives required by the experiment, and adjusts the set values ​​of the basic loop control of temperature and liquid level to achieve optimization of operation indicators.

[0026] In this embodiment, the controlled object unit consists of a stainless steel heating tank with a diameter × height of F450 × 500 mm, a 380V electric heater, a stainless steel convection heat exchanger with a diameter × length of F250 × 400 mm, water pump A, water pump B, a stainless steel water storage tank A with a length × width × height of 800 × 550 × 400 mm, a stainless steel water storage tank B with a length × width × height of 600 × 450 × 400 mm, and corresponding pipelines. The above equipment is arranged according to... Figure 1 The connection is made in this way.

[0027] The frequency converters for pumps A and B in the actuator are both Siemens MICROMASTER 440 frequency converters. The electric heater voltage regulation module is model LSA-TH3P. The thermometer is a model Pt100 resistance temperature sensor. The flow meter is a model LWGY-10(LW) / NI / 05 / S / S / N / N turbine flow meter. The level gauge is a model UCI-1 magnetic float reversing level gauge. The power meter is an ABB Emax2 general-purpose intelligent power meter (with 4~20mA output). The process control system uses a Siemens S7-1500 series PLC control system and engineering station. The basic loop controller and operator monitoring software are configured using Siemens TIA Portal software.

[0028] In this embodiment, the operation control unit uses a regular PC as the operation control computer, and MATLAB software is used to program the operation optimization control software. The OPC protocol is used to realize data interaction between the operation control computer and the Siemens S7-1500 PLC and its engineering station. The operation optimization control software reads and records process data such as temperature, liquid level, flow rate, and power from the Siemens S7-1500 PLC. According to the optimization algorithm required by the experiment, it calculates and adjusts the set values ​​of the heating tank temperature control loop and the heating tank liquid level control loop to achieve the optimization of operation indicators.

[0029] In this embodiment, a physical experimental method for optimizing and controlling the operation of an industrial heat exchange process includes the following steps: Step 1: In the process control system, construct three basic loop controllers, including a heating device temperature controller, a heating device liquid level controller, and a heat exchange device cold water outlet temperature controller. The controlled variable of the temperature controller of the heating device is the temperature of the hot water generated inside the heating device as measured by thermometer A, and the control quantity is the heating command of the electric heater pressure regulating module. The controlled variable of the heating device level controller is the water level height in the heating device measured by the level gauge, and the control quantity is the frequency command of the water pump A frequency converter. The controlled variable of the cold water outlet temperature controller of the heat exchange device is the cold water outlet temperature of the heat exchange device measured by thermometer B, and the control quantity is the frequency command of the frequency converter of water pump B. Step 2: Define the operational indicators for optimizing the operation of the controlled object, including energy consumption indicators, output indicators, heating medium consumption indicators, and comprehensive indicators; Among them, the energy consumption index = power of water pump A + power of water pump B + power of electric heater; Production index = Instantaneous flow rate of the outlet pipe of pump B as measured by flow meter B; Heating medium consumption index = instantaneous flow rate of the outlet pipe of pump A measured by flow meter A; The comprehensive indicator is a weighted index of any two or three of the following: energy consumption, heating medium consumption, and output. Step 3: Define the decision variables for optimizing the operation of the controlled object; The decision variables for optimizing the operation of the controlled object include the setpoints of the heating device temperature controller and the heating device liquid level controller. Step 4: Define the optimization control problem for the controlled object; The controlled object operation optimization control problem is defined as follows: Under the premise that the three basic loop controllers constructed in step 1 are put into closed-loop control and specific constraints are met (such as ensuring that the cold water outlet temperature of the heat exchange device meets the standard and that each operating index meets the upper and lower limit requirements), how to adjust the two decision variables mentioned in step 3 so that the operating index mentioned in step 2 is optimized (such as minimizing energy consumption, minimizing working fluid consumption, and maximizing output). Step 5: Start the equipment (pump A, pump B, and electric heater) used in the hot water loop and cold water loop of the controlled object unit through the process control unit, and put the three basic loop controllers into automatic control mode. When the water flow in the controlled object unit enters a steady state, start the operation optimization control software containing a specific optimization algorithm of the operation control unit, and adjust the set values ​​of the heating device temperature controller and heating device liquid level controller online according to the process data of the controlled object unit, and carry out experimental research on optimizing the operation indicators.

[0030] In this embodiment, firstly, in the Siemens S7-1500 series PLC control system, according to... Figure 2The diagram shows the construction of a heating tank temperature controller, a heating tank level controller, and a heat exchanger cold water outlet temperature controller. Each controller is a PID controller, and the ZN tuning method is used to tune the controller parameters, so that each basic loop controller has good tracking performance. Then, the energy consumption index is used as the operating index to be optimized. The energy consumption index = power of water pump A frequency converter + power of water pump B frequency converter + power of electric heater; the output index, i.e. the flow rate of water in water path B measured by flow meter B, is used as the interval constraint condition. Select the setpoints of the heating tank temperature controller and the heating tank level controller as decision variables; The operation optimization control problem is defined as follows: Under the premise that the three basic loop controllers are put into closed-loop control and the cold water outlet temperature of the heat exchange device meets the standard, and the production index meets the interval constraints, how to adjust the two decision variables, the set value of the heating tank temperature controller and the set value of the heating tank liquid level controller, so that the energy consumption index is minimized as much as possible. Finally, a physical experiment on the operation optimization control of an industrial heat exchange process was conducted. The process of a single experiment was as follows: Step S1: Start the experimental setup. First, fill water tanks A and B with water. Manually start water pump A to inject the pre-set amount of water (working medium) into the heating tank, then stop water pump A. Manually turn on the electric heater to heat the working medium to the required temperature. After confirming that all equipment in the experimental setup is in normal condition, start water pump A, water pump B, and the electric heater in sequence. Manually adjust each device in the actuator until the parameters tend to stabilize, then put the three basic loop controllers into automatic control mode. Step S2: Operation index optimization. After the three basic loop controllers reach steady-state operation, the operation optimization control software uses the experimental intelligent optimization algorithm to iteratively optimize the operation index based on the energy consumption index. After calculating the two decision variables, namely the set value of the heating tank temperature controller and the set value of the heating tank liquid level controller, the values ​​of the two decision variables are downloaded to the two basic loop controllers. Step S3: Optimization and iteration. After the new setpoint is loaded, the operating status of the process control system is continuously monitored. After the three basic loop controllers reach steady state again, the current energy consumption index can be calculated and compared with the previous energy consumption index to evaluate the previous optimization effect. The two decision variables are then iterated and optimized again. The above optimization-verification process is repeated until the expected optimization goal is achieved.

[0031] Step S4: End the experiment. After completing the optimization test, shut down all equipment step by step according to the safety procedures, drain the water from the heating tank, heat exchange device and pipeline, and restore the experimental device to its initial state.

Claims

1. A physical experimental device for optimizing and controlling the operation of an industrial heat exchange process, characterized in that: This includes the controlled object unit, the process control unit, and the operation control unit; The controlled object unit is set as the controlled object for the operation optimization control experiment, including a hot water loop, a cold water loop and a heat exchange device; the hot water loop provides a heating medium to the heat exchange device through heating, and the heat exchange device exchanges heat with the cold water in the cold water loop through the heat source provided by the hot water loop; Throughout the operation of the controlled object, the heated water flow in the hot water loop is considered as the heating medium used to heat the water flow in the cold water loop, while the water flow in the cold water loop at the cold water outlet of the heat exchanger is considered as a product that meets the quality requirements. The process control unit detects the process parameters of the controlled object in real time, receives setpoint instructions from the operation control unit, and realizes basic loop control of the temperature and liquid level of the controlled object by adjusting the control instructions. In addition, the process control unit also has the function of starting and stopping the equipment used in the hot water loop and cold water loop. The main body of the operation control unit is an operation control computer, which is connected to the process control unit via a network. The operation control computer executes operation optimization control software, which reads and records industrial heat exchange process data from the process control unit, performs specific optimization algorithm calculations based on the optimization objectives required by the experiment, and adjusts the set values ​​of the basic loop control of temperature and liquid level to achieve optimization of operation indicators. The hot water loop includes a water storage tank A, a water pump A, a heating device, and corresponding pipelines. The outlet of the water storage tank A is connected to the input end of the water pump A via a pipeline, and the output end of the water pump A is connected to the top inlet of the heating device via a pipeline. The heating device has both electric heating and water storage functions. An electric heater is installed at the bottom of the heating device to heat the water injected into the heating device via the water pump A. The bottom outlet of the heating device is connected to the hot water inlet of the heat exchange device via a pipeline, and the water flow returns from the hot water outlet of the heat exchange device to the water storage tank A via a pipeline. The cold water loop includes a water storage tank B, a water pump B, and corresponding pipelines. The outlet of the water storage tank B is connected to the input end of the water pump B via a pipeline, and the output end of the water pump B is connected to the cold water inlet of the heat exchange device via a pipeline. The water flow returns from the cold water outlet of the heat exchange device to the water storage tank B via a pipeline. The installation position of the heating device should be higher than the installation position of the heat exchange device, and the installation position of the heat exchange device should be higher than the installation positions of the water storage tank A and the water storage tank B, so as to ensure that the hot water loop can flow from the heating device through the heat exchange device back to the water storage tank A by gravity, and the cold water loop can flow from the heat exchange device back to the water storage tank B by gravity.

2. The physical experimental device for optimizing and controlling the operation of an industrial heat exchange process according to claim 1, characterized in that: The heat exchange device has a hot water inlet, a hot water outlet, a cold water inlet, and a cold water outlet. The hot water loop flow and the cold water loop flow exchange heat in the heat exchange device, but no material contact or material exchange occurs.

3. The physical experimental device for optimizing and controlling the operation of an industrial heat exchange process according to claim 2, characterized in that: The process control unit includes an actuator, a detection instrument, and a process control system. The process control system sends control commands to the actuator. The actuator receives the control commands from the process control system and drives water pump A, water pump B, and an electric heater. The detection instrument measures the instantaneous water flow rate at the outlet pipes of water pump A and water pump B, the instantaneous liquid level of the water stored in the heating device, the temperature of the hot water inside the heating device and the temperature of the cold water outlet of the heat exchange device, as well as the motor power of water pump A, the motor power of water pump B, and the power of the electric heater. The detection instrument connects to the process control system and sends the detected process parameters to the process control system. The process control system receives temperature, flow rate, liquid level, and power signals from the detection instrument, constructs a basic loop controller for temperature and liquid level, and sends corresponding control commands to the actuator to ensure that the controlled variables of each basic loop controller track their set values.

4. The physical experimental device for optimizing and controlling the operation of an industrial heat exchange process according to claim 3, characterized in that: The actuator includes a frequency converter for water pump A, a frequency converter for water pump B, and a voltage regulating module for an electric heater. The frequency converters for water pump A and water pump B respectively receive frequency commands from the process control system, drive water pump A and water pump B, and convert the frequency commands into the rotational speeds of water pump A and water pump B, thereby regulating the water flow rates of water pump A and water pump B. The voltage regulating module for the electric heater receives heating commands from the process control system, drives the electric heater, and adjusts the heating intensity of the electric heater according to the heating commands.

5. The physical experimental device for optimizing and controlling the operation of an industrial heat exchange process according to claim 4, characterized in that: The detection instruments include flow meter A, flow meter B, level gauge, thermometer A, thermometer B, power meter for water pump A, power meter for water pump B, and power meter for electric heater. Flow meter A is installed on the outlet pipe of water pump A to measure the instantaneous water flow rate of the outlet pipe of water pump A online. Flow meter B is installed on the outlet pipe of water pump B to measure the instantaneous water flow rate of the outlet pipe of water pump B online. The level gauge is installed in the heating device to measure the instantaneous water level stored in the heating device online. The thermometer A is installed inside the heating device near the bottom outlet of the heating device to measure the hot water temperature inside the heating device online. The thermometer B is installed at the cold water outlet of the heat exchange device to detect the cold water outlet temperature of the heat exchange device online. The power meters for water pump A, water pump B, and electric heater are respectively connected to the motors of water pump A, water pump B, and electric heater to measure the power of water pump A, water pump B, and electric heater online. All detection instruments are connected to the process control system via hard-wired signals or fieldbus signals to send the detected process parameters to the process control system.

6. A physical experimental method for optimizing and controlling the operation of an industrial heat exchange process, implemented using the physical experimental apparatus for optimizing and controlling the operation of an industrial heat exchange process as described in claim 5, characterized in that: The steps include the following: Step 1: In the process control unit, construct three basic loop controllers, including a heating device temperature controller, a heating device liquid level controller, and a heat exchange device cold water outlet temperature controller. The controlled variable of the temperature controller of the heating device is the temperature of the hot water generated inside the heating device as measured by thermometer A, and the control quantity is the heating command of the electric heater pressure regulating module. The controlled variable of the heating device level controller is the water level height in the heating device measured by the level gauge, and the control quantity is the frequency command of the water pump A frequency converter. The controlled variable of the cold water outlet temperature controller of the heat exchange device is the cold water outlet temperature of the heat exchange device measured by thermometer B, and the control quantity is the frequency command of the frequency converter of water pump B. Step 2: Define the operational metrics for optimizing the controlled object; Step 3: Define the decision variables for optimizing the operation of the controlled object; The decision variables for optimizing the operation of the controlled object include the setpoints of the heating device temperature controller and the heating device liquid level controller. Step 4: Define the optimization control problem for the controlled object; The controlled object operation optimization control problem is defined as follows: Under the premise that the three basic loop controllers constructed in step 1 are put into closed-loop control and meet specific constraints, how to adjust the two decision variables in step 3 so that the operation index in step 2 is optimized; Step 5: Start the equipment used in the hot water loop and cold water loop of the controlled object unit through the process control unit, and put the three basic loop controllers into automatic control mode. When the water flow of the controlled object unit enters a steady state, start the operation optimization control software containing a specific optimization algorithm of the operation control unit, and adjust the set values ​​of the heating device temperature controller and heating device liquid level controller online according to the process data of the controlled object unit, and carry out experiments to optimize the operation indicators.

7. The physical experimental method for optimizing and controlling the operation of an industrial heat exchange process according to claim 6, characterized in that: Step 2 defines the operational indicators for optimizing the operation of the controlled object, including energy consumption indicators, output indicators, heating medium consumption indicators, and comprehensive indicators. Among them, the energy consumption index = power of water pump A + power of water pump B + power of electric heater; Production index = Instantaneous flow rate of the outlet pipe of pump B as measured by flow meter B; Heating medium consumption index = instantaneous flow rate of the outlet pipe of pump A measured by flow meter A; The comprehensive index is a weighted index of any two or three of the following: energy consumption index, heating medium consumption index, and output index.

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