Multi-parameter adjustable experimental test platform for drum dryer

Abstract

The invention relates to a multi-parameter adjustable experimental test platform for a drum dryer. The multi-parameter adjustable experimental test platform comprises an air treatment part, a drum part and a control system part, the air treatment part is used for providing airflow with independent and controllable thermodynamic parameters for the roller part; the roller part is used for enabling a fabric load and airflow to complete heat and humidity exchange under the control of roller control parameters; the control system part comprises an operation layer and a monitoring layer, and the monitoring layer is used for monitoring thermodynamic parameters of each node and the mass of a fabric load and realizing full-process automatic control of an experiment; the operation layer comprises an air treatment subsystem and a roller movement subsystem, and the air treatment subsystem is used for independently regulating and controlling thermodynamic parameters of airflow provided by the air treatment part according to the monitored thermodynamic parameters of all nodes; the roller motion subsystem is used for adjusting roller control parameters. According to the method, the independent effect and the interaction effect of each parameter can be effectively separated, and the experiment repeatability and the data credibility are improved.

Description

Technical Field

[0001] This invention relates to the field of clothing drying test technology, and in particular to a multi-parameter adjustable test platform for tumble dryers. Background Technology

[0002] Tumble dryers are among the most energy-intensive household appliances, and improving their energy efficiency has become an important research direction. Among them, direct-vent tumble dryers have become the mainstream configuration in residential and commercial settings due to their simple mechanical structure, low initial cost, and high drying efficiency. Furthermore, their linear thermodynamic path—comprising air intake, sensible heat heating, and direct exhaust—avoids interference from internal heat recovery or closed-loop effects, defining a clear and stable system boundary for heat and mass transfer analysis, and is widely regarded as an important benchmark for tumble dryer research.

[0003] The essence of drum drying is a coupled heat and mass transfer process between heated airflow and the mechanically agitated fabric inside the rotating drum. Its drying performance is determined by two interacting parameter systems: first, the thermo-humidity-aerodynamic state on the air inlet side, encompassing core parameters such as temperature, humidity, and flow rate; and second, the kinematic characteristics on the drum side, including key indicators such as motion sequence, rotation speed, direction of rotation, and operating time. A thorough understanding of the heat and mass transfer mechanism and the construction of a high-precision drying kinetic model are prerequisites for improving the energy efficiency of dryers and optimizing drying strategies.

[0004] However, existing experimental testing platforms for drum drying research have significant technical shortcomings, making it difficult to meet the aforementioned research needs. On the one hand, there is a general lack of dedicated air humidity parameter control equipment, hindering precise and independent control of thermo-humidity-aerodynamic parameters. On the other hand, the control of drum kinematic parameters is mostly limited to simplified motion modes, such as constant-speed unidirectional rotation or basic symmetrical bidirectional operation, with limited support for programmable, time-analyzed sequences, making it impossible to achieve more complex motion strategies such as intermittent tumbling, asymmetric bidirectional speed, and independently configurable rotation-pause cycles. In summary, existing platforms fail to achieve wide-range, independent, and coordinated control of air conditions and complex drum kinematic parameters, thus failing to meet the practical needs of drum drying equipment and technology research. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a multi-parameter adjustable experimental testing platform for tumble dryers, which can effectively separate the independent effects and interactions of each parameter, and improve experimental repeatability and data reliability.

[0006] The technical solution adopted by the present invention to solve its technical problem is: to provide a multi-parameter adjustable experimental test platform for a drum dryer, including an air handling part, a drum part and a control system part;

[0007] The air handling section is used to provide the drum section with airflows whose thermodynamic parameters are independently controllable; the thermodynamic parameters include moisture content, dry air mass flow rate, and temperature;

[0008] The roller section is connected to the output end of the air handling section and is used to enable the fabric load to complete heat and moisture exchange with the airflow under the control of the roller control parameters; the roller control parameters include motion sequence, rotation speed and stage duration.

[0009] The control system includes an operation layer and a monitoring layer. The monitoring layer is used to monitor the thermodynamic parameters of each node and the mass of the fabric load, as well as to realize the full-process automated control of the experiment. The operation layer includes an air handling subsystem and a roller motion subsystem. The air handling subsystem is used to independently adjust the thermodynamic parameters of the airflow provided by the air handling section according to the monitored thermodynamic parameters of each node. The roller motion subsystem is used to adjust the roller control parameters.

[0010] The air handling section includes an air pretreatment module, an air delivery module, and an air reheating module connected in sequence.

[0011] The air pretreatment module is equipped with a pretreatment chamber with heat insulation function and a constant temperature and humidity machine. The constant temperature and humidity machine is used to regulate the humidity of the air in the pretreatment chamber.

[0012] The air delivery module is equipped with a variable frequency fan, which is used to adjust the mass flow rate of dry air.

[0013] The air reheating module is equipped with an electric heater, which is used to regulate the temperature of the air.

[0014] The air handling subsystem includes a humidity control module, which is used to calculate the deviation between the temperature and humidity in the pretreatment room collected in real time by the monitoring layer and the preset target temperature and humidity, and to adjust the constant temperature and humidity machine based on the deviation so that the humidity of the air in the pretreatment room reaches the target humidity.

[0015] The air handling subsystem includes a frequency control module, used to adjust the frequency of the inverter of the variable frequency fan according to the target dry air mass flow rate using a mapping model; the mapping model is obtained by adjusting the frequency of the inverter of the variable frequency fan, and the monitoring layer monitors the airflow speed in real time to obtain the frequency-wind speed mapping relationship; the measured wind speed is linearly converted into dry air mass flow rate using the fan characteristic parameters and aerodynamic correlation logic to obtain the wind speed-dry air mass flow rate mapping relationship; the frequency-wind speed mapping relationship and the wind speed-dry air mass flow rate mapping relationship are combined to obtain the mapping model.

[0016] The air handling subsystem includes a temperature control module, which calculates the deviation between the temperature of the airflow collected in real time by the monitoring layer and the preset target airflow temperature, and performs PID control on the electric heater based on the deviation so that the temperature of the airflow reaches the target airflow temperature.

[0017] The roller motion subsystem controls the roller section to perform a four-stage bidirectional alternating sequential cyclic motion via an external frequency converter. The four-stage bidirectional alternating sequential cyclic motion includes: a counterclockwise rotation phase, a first stop and hold phase, a clockwise rotation phase, and a second stop and hold phase. The running time of both the counterclockwise and clockwise rotation phases includes the motor rotation time and the inertia compensation pause time. The inertia compensation pause time is used to asymmetrically align the timing of the motor control commands with the timing of the roller's physical motion.

[0018] The air ducts within the air handling section and the air duct between the air handling section and the roller section are constructed from one or more of the following: high-temperature resistant silicone vulcanized air ducts, stainless steel air ducts, and galvanized air ducts; the connection nodes of each air duct are sealed with flanges, clamps, sealant, and aluminum foil tape, and the outside of the air ducts is covered with thermal insulation material.

[0019] The monitoring layer supports both a fixed-parameter configuration mode and a phased-parameter configuration mode for the entire process of automated control of the experiment. The fully automated control process includes load mass termination conditions and drying time termination conditions. The load mass termination condition means that the experiment terminates when the fabric load reaches a preset target load mass. The drying time termination condition means that the experiment terminates when the fabric load drying time reaches a preset target drying time. The fixed-parameter configuration mode involves setting a set of experimental parameters before the experiment, including thermodynamic parameters, drum control parameters, and termination conditions. During the experiment, the air handling subsystem follows the set parameters. The thermodynamic parameters control the air handling section, and the drum motion subsystem controls the drum section according to the set drum control parameters until the set termination condition is reached. The phased parameter configuration mode refers to setting multiple sets of experimental parameters before the experiment. Each set of experimental parameters includes thermodynamic parameters, drum control parameters, and termination conditions. During the experiment, the air handling subsystem first controls the air handling section according to the thermodynamic parameters in the first set of experimental parameters, and then controls the drum section according to the drum control parameters in the first set of experimental parameters until the termination condition in the first set of experimental parameters is reached. After completion, the experiment is carried out based on the next set of experimental parameters until all sets of experimental parameters are completed.

[0020] By adopting the above-mentioned technical solutions, this invention has the following advantages and positive effects compared with the prior art: The air handling section of this invention can independently control three thermodynamic parameters: moisture content, dry air mass flow rate, and temperature, providing a stable and controllable airflow for the drum section and effectively avoiding parameter cross-interference. The drum section of this invention, in conjunction with programmable motion sequences, rotation speed, and other control parameters, achieves controllable adjustment of the heat and moisture exchange process between the fabric and the airflow, meeting the experimental requirements of complex motion strategies. The control section of this invention adopts a two-layer control system. The monitoring layer monitors the parameters of the entire process in real time, while the operation layer accurately feeds back and controls the air and drum-related parameters, realizing the programmed setting and automated execution of experimental parameters, ensuring stable experimental boundary conditions and synchronous data acquisition. The entire experimental platform effectively separates the independent effects and interactions of each parameter, improving experimental repeatability and data reliability, and providing a standardized and reproducible scientific experimental platform for the study of heat and mass transfer mechanisms in drum dryers, energy efficiency optimization, and the development of drying strategies. Attached Figure Description

[0021] Figure 1 This is a schematic diagram illustrating the design concept of a multi-parameter adjustable experimental testing platform for a drum dryer according to an embodiment of the present invention.

[0022] Figure 2 This is a hardware schematic diagram of a multi-parameter adjustable experimental testing platform for a drum dryer according to an embodiment of the present invention.

[0023] Figure 3 This is a schematic diagram of the internal electrical component configuration of the control cabinet in an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram illustrating the classification of standard program types for the experimental platform in this embodiment of the invention;

[0025] Figure 5 This is a schematic diagram of the experimental procedure in an embodiment of the present invention;

[0026] Figure 6 This is a logical diagram illustrating the adjustment of various parameters in an embodiment of the present invention. Detailed Implementation

[0027] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0028] Embodiments of the present invention relate to a multi-parameter adjustable experimental testing platform for a tumble dryer, such as... Figure 1 As shown, it includes:

[0029] Air handling section A is used to provide airflow with independently controllable thermodynamic parameters to the drum section; wherein, the thermodynamic parameters include moisture content, dry air mass flow rate and temperature.

[0030] Roller section B is connected to the output end of the air treatment section and is used to enable the fabric load to complete heat and moisture exchange with the airflow under the control of roller control parameters; wherein, the roller control parameters include motion sequence, rotation speed and stage duration.

[0031] The control system section C includes an operation layer and a monitoring layer. The monitoring layer is used to monitor the thermodynamic parameters of each node and the mass of the fabric load, as well as to realize the full-process automated control of the experiment. The operation layer includes an air handling subsystem and a roller motion subsystem. The air handling subsystem is used to independently adjust the thermodynamic parameters of the airflow provided by the air handling section according to the monitored thermodynamic parameters of each node. The roller motion subsystem is used to adjust the roller control parameters.

[0032] like Figure 2 As shown, the air handling section in this embodiment includes an air pretreatment module, an air delivery module, and an air reheating module connected sequentially via air ducts. The air pretreatment module is equipped with a heat-insulated pretreatment chamber and a constant temperature and humidity unit b. The constant temperature and humidity unit b is used to regulate the humidity content of the air in the pretreatment chamber and performs the air pretreatment function, providing a basic air source with controllable humidity for the platform. The air delivery module is equipped with a variable frequency fan c, which is used to adjust the dry air mass flow rate. As the power element for air delivery, the variable frequency fan c enables independent control of the dry air mass flow rate. The air reheating module is equipped with an electric heater d, which is used to regulate the air temperature. The electric heater d is responsible for the sensible heat reheating of the air, precisely adjusting the inlet air temperature of the drum without changing the air humidity content.

[0033] In this embodiment, the drum section serves as the core carrier for fabric drying and tumbling. Its prototype is a commercial drum dryer e. To match the platform's centralized air supply and heating system, the original built-in centrifugal fan, heating element, and air duct were removed and replaced with external supporting components (i.e., the air handling unit and related supporting components). At the same time, the capacitor of its single-phase capacitor-driven asynchronous motor was removed, and the motor operation was controlled by an external frequency converter driver to achieve precise control of the drum's rotational speed, direction, and running / stopping time.

[0034] The control system in this embodiment is housed in control cabinet a, which integrates multiple electrical components and serves as the core of the platform's automated operation. The monitoring layer of the control system can be a customized PLC-HMI centralized monitoring and data acquisition system based on a programmable logic controller (PLC) and a touchscreen. It connects to the sensors and actuators of the air handling subsystem and the variable frequency drive of the roller kinematics subsystem via an RS485 Modbus bus. Simultaneously, it accesses a distributed sensor network to achieve coordination among subsystems, programmed parameter setting, equipment linkage control, automated execution of experimental procedures, and synchronous acquisition and storage of multi-domain data.

[0035] The distributed sensor network in this embodiment includes: electricity meters S8-S11 (see...) Figure 3 The system comprises four sensors: a constant temperature and humidity machine (b), a variable frequency fan (c), an electric heater (d), and a modified commercial drum dryer (e). Temperature and humidity transmitters S1-S4 monitor the temperature and relative humidity of the drying airflow before pretreatment, after pretreatment, after reheating, and after exiting the drum. Wind speed transmitters S5 and S6 monitor the wind speed at the drum inlet and outlet, respectively. A weighing device S7 monitors changes in load mass during the drying process. This distributed sensor network uses a polling mechanism to collect data on various parameters throughout the platform's operation, providing data support for precise parameter control and quantitative analysis of experimental results. All sensors and instruments are uniformly connected to an RS485 Modbus bus network to ensure time synchronization and consistency of data acquisition.

[0036] The air handling subsystem of the operating layer in this embodiment includes a humidity control module, a frequency control module, and a temperature control module. These three modules regulate air humidity, airflow, and temperature respectively through core components: a constant temperature and humidity unit, a variable frequency fan, and a heater. The final control target values ​​are three thermodynamically independent variables: humidity content, dry air mass flow rate, and temperature. Figure 6 As shown, the adjustment methods for each parameter are as follows:

[0037] The humidity control module is used to calculate the deviation between the temperature and humidity in the pretreatment room detected by the temperature and humidity transmitter S1 in real time and the preset target temperature and humidity, and adjust the constant temperature and humidity machine based on the deviation so that the humidity of the air in the pretreatment room reaches the target humidity, thereby maintaining the target pretreatment air state and completing the closed-loop regulation.

[0038] The frequency control module is used to adjust the frequency of the inverter of the variable frequency fan according to the target dry air mass flow rate using a mapping model, so as to achieve precise control of the dry air mass flow rate. The mapping model is obtained in the following way:

[0039] The frequency of the inverter of the variable frequency fan is adjusted, and the wind speed is monitored in real time by the wind speed sensor S5 to obtain the frequency-wind speed mapping relationship. The measured wind speed is linearly converted into dry air mass flow rate by using the fan characteristic parameters and aerodynamic correlation logic to obtain the wind speed-dry air mass flow rate mapping relationship. The mapping model can be obtained by combining the frequency-wind speed mapping relationship and the wind speed-dry air mass flow rate mapping relationship.

[0040] The temperature control module is used to calculate the deviation between the temperature of the airflow, which is collected in real time by the temperature and humidity transmitter S3, and the preset target airflow temperature. Based on the deviation, the module performs PID control on the electric heater so that the temperature of the airflow reaches the target airflow temperature, thereby achieving airflow temperature regulation.

[0041] In this embodiment, the roller motion subsystem controls the roller section to perform a four-stage bidirectional alternating sequential cyclic motion via an external frequency converter. This four-stage bidirectional alternating sequential cyclic motion includes: a counter-clockwise rotation phase (including acceleration, constant speed, and deceleration), a first stop holding phase, a clockwise rotation phase (including acceleration, constant speed, and deceleration), and a second stop holding phase. This cyclic motion sequence is repeated continuously until program termination, providing controllable and repeatable fabric tumbling under preset kinematic conditions. The roller speed is controlled by changing the motor input frequency; the running duration of both the counter-clockwise and clockwise rotation phases includes the motor rotation time and the inertia compensation pause time. The design logic of the inertia pause compensation period is to asymmetrically align the motor control command timing with the physical motion timing of the roller. For example, after each active rotation phase, a fixed duration (e.g., 3 seconds) is set to compensate for the roller inertia, ensuring that the roller has completed the deceleration to a stop before entering the stationary holding phase, thereby ensuring a smooth direction change.

[0042] like Figure 3As shown, the electrical components integrated inside the control cabinet in this embodiment cover all functional dimensions such as control, operation, protection, and transmission. The main configuration includes: a.1 a human-machine interface touchscreen, used for visual configuration of experimental parameters and real-time monitoring of platform operation status; a.2~a.4 operation buttons, serving as manual operation control elements for the platform; a.5~a.11 circuit breakers and a.23~a.25 contactors, jointly undertaking the protection and load switching functions of the electrical circuit; a.12 switching power supply, providing stable power to each electrical component; a.13~a.14 frequency converters, used to regulate the operation of the variable frequency fan and drum motor respectively; a.15 programmable logic controller (PLC), serving as the central processing unit of the platform, controlling each component through RS485 communication; a.16~a.22 intermediate relays, realizing the relay and amplification of control signals; a.26~a.29 terminal blocks, responsible for the conditioning and wiring management of various signals, ensuring the neatness of the internal wiring and the stability of signal transmission within the control cabinet.

[0043] The workflow of the multi-parameter adjustable experimental testing platform for a tumble dryer in this embodiment is as follows: Outdoor air first enters a pre-treatment chamber with heat insulation, and the humidity content of the indoor air is regulated by a constant temperature and humidity machine (b). The pre-treated air is then transported by a variable frequency fan (c), which can independently adjust the airflow. The air is then reheated to the target temperature by an electric heater (d), and finally enters the tumble dryer to complete heat and moisture exchange with the fabric load. The exhaust gas is then directly discharged to the outdoor environment. Simultaneously, the tumble dryer operates independently in a programmable motion mode, thereby achieving controlled regulation of fabric agitation during the drying process. All equipment and components of the experimental testing platform in this embodiment, including the air handling module, piping, sensors, and the tumble dryer, can be installed in a dedicated laboratory with stable environmental conditions to minimize environmental disturbances.

[0044] To ensure the airtightness and stability of the air supply in the experimental testing platform of this embodiment, and to achieve a smooth connection between the entire process of air introduction, pretreatment, transportation, reheating, and exhaust, this embodiment, in addition to the core functional components, is equipped with dedicated auxiliary pipelines and sealing and insulation materials. The pipeline routing and interface locations are clearly planned, laying the hardware foundation for precise parameter control. The auxiliary materials and pipeline system of the experimental testing platform of this embodiment are laid out around the air handling process, and are mainly divided into two parts: pipeline ducts and interfaces, and sealing and insulation materials. The specific design and configuration are as follows:

[0045] (1) Pipeline and ductwork: The pipeline is constructed from various special ducts such as high-temperature resistant silicone vulcanized duct, stainless steel duct, and galvanized duct. From the outdoor air inlet to the air outlet after drying, arrows are used to indicate the flow direction of the drying medium air along the pipeline. According to the air handling process, constant temperature and humidity machine b, variable frequency fan c, electric heater d and modified drum dryer e are connected in series to build a complete air transport link from fresh air input to exhaust gas discharge, ensuring the smooth operation of the entire air handling process, and realizing intuitive traceability of airflow path.

[0046] (2) Sealing and insulation materials: To ensure the airtightness and thermal stability of the pipeline system, flanges, clamps, sealant, and aluminum foil tape are used to seal the connection nodes of each air duct and functional component to effectively prevent air leakage and reduce the deviation of control accuracy caused by leakage. At the same time, insulation materials (not shown in the schematic diagram) are laid on the outside of the air duct to minimize heat loss during air reheating, which not only improves the energy utilization efficiency of the platform, but also effectively maintains the stability of air temperature throughout the experiment, further ensuring the accuracy of temperature control.

[0047] In this implementation, all experiments and tests are performed within a deterministic automation framework using a PLC. First, variable parameters and program termination conditions are set on the HMI interface. Then, the PLC automatically initiates the entire experimental process: pretreatment → air supply → heating → drum movement. During the experiment, measurement data is collected synchronously. When the experimental data reaches the preset termination condition, the system automatically stops and saves all experimental data. The termination condition refers to determining program termination based on the load mass (fabric moisture content) or drying time; that is, the experiment terminates when the fabric load mass reaches the preset target load mass, or when the fabric load drying time reaches the preset target drying time.

[0048] The experimental testing platform of this embodiment also supports a fixed parameter configuration mode throughout the entire process and a phased parameter configuration mode. The fixed parameter configuration mode involves setting a set of experimental parameters before the experiment, including thermodynamic parameters, drum control parameters, and termination conditions. During the experiment, the air handling subsystem controls the air handling section according to the set thermodynamic parameters, and the drum motion subsystem controls the drum section according to the set drum control parameters, until the set termination conditions are reached. The phased parameter configuration mode involves setting multiple sets of experimental parameters before the experiment, each set including thermodynamic parameters, drum control parameters, and termination conditions. During the experiment, the air handling subsystem first controls the air handling section according to the thermodynamic parameters in the first set of experimental parameters, and then controls the drum section according to the drum control parameters in the first set of experimental parameters, until the termination conditions in the first set of experimental parameters are reached. After completion, the experiment is then conducted based on the next set of experimental parameters, until all sets of experimental parameters are completed.

[0049] like Figure 4 As shown, the experimental testing platform of this embodiment uses a 2×2 matrix (termination condition: load mass or drying time; parameter configuration mode: full-process configuration parameters or staged configuration parameters) to implement four standard program types. Figure 5 As shown, in Program 1 under the fixed parameter configuration mode, the PLC compares the monitored load quality with the preset threshold 1 in real time. In Program 3 under the same fixed parameter configuration mode, the PLC compares the monitored drying time with the preset threshold 1 in real time. The program terminates when either the load quality or drying time reaches the preset threshold. In Program 2 under the phased parameter configuration mode, the PLC triggers a phase switching signal based on the real-time monitored load quality compared with preset thresholds 1 and 2, and automatically updates all relevant parameter settings, ultimately using the preset threshold 3 as the program termination criterion. In Program 4 under the same phased parameter configuration mode, the PLC triggers a phase switching signal based on the real-time monitored drying time compared with preset thresholds 1 and 2, and automatically updates all relevant parameter settings, ultimately using the preset threshold 3 as the program termination criterion. During the experiment, multiple sensors synchronously acquire data, ensuring logical synchronization between experimental actions and data acquisition, effectively suppressing operator-introduced randomness and establishing a deterministic experimental baseline. All measurements are visualized in real time via a human-machine interface (HMI) and can be exported for post-processing and quantitative analysis.

[0050] It is easy to see that this implementation method, in order to achieve independent and high-precision control, constructs a complete collaborative control method at three levels: operation, control, and function. From hardware structure and control logic to experimental execution, it ensures precise and independent parameter control across all dimensions. Firstly, at the operation level, all experimental procedures, including parameter configuration, process execution, parameter switching, stage switching, and data acquisition, are fully automated through a programmable logic controller and touchscreen system. This integrates all operations into a unified time-series management system, reducing variability introduced by operators in terms of timing and sequence, as well as errors caused by manual operation, ensuring high repeatability of the experiment, while also guaranteeing the stability and consistency of experimental boundary conditions. At the control level, air handling and drum movement are managed by independent control loops and coordinated at the monitoring layer. Based on the physical separation of pretreatment, air supply, and reheating modules, the inlet air state is regulated using humidity ratio, dry air mass flow rate, and temperature as thermodynamically independent control targets, avoiding the cross-interference of variables common in integrated dryer control. Simultaneously, the drum kinematics are independently controlled, thereby achieving separate control of heat, humidity, aerodynamics, and mechanical inputs. At the functional level, through a modular hardware architecture, a PLC centralized monitoring framework, and an independent parameter control strategy, the clear definition and independent programmable control of the air-side working conditions and the kinematic parameters of the drum side are realized, thereby supporting the systematic study of the effects of single parameters and the interaction of controlled multiple parameters.

Claims

1. A multi-parameter adjustable experimental testing platform for tumble dryers, characterized in that, This includes the air handling unit, the drum unit, and the control system unit; The air handling section is used to provide the drum section with airflows whose thermodynamic parameters are independently controllable; the thermodynamic parameters include moisture content, dry air mass flow rate, and temperature; The roller section is connected to the output end of the air handling section and is used to enable the fabric load to complete heat and moisture exchange with the airflow under the control of the roller control parameters; the roller control parameters include motion sequence, rotation speed and stage duration. The control system includes an operation layer and a monitoring layer. The monitoring layer is used to monitor the thermodynamic parameters of each node and the mass of the fabric load, as well as to realize the full-process automated control of the experiment. The operation layer includes an air handling subsystem and a roller motion subsystem. The air handling subsystem is used to independently adjust the thermodynamic parameters of the airflow provided by the air handling section according to the monitored thermodynamic parameters of each node. The roller motion subsystem is used to adjust the roller control parameters.

2. The multi-parameter adjustable experimental testing platform for a tumble dryer according to claim 1, characterized in that, The air handling section includes an air pretreatment module, an air delivery module, and an air reheating module connected in sequence. The air pretreatment module is equipped with a pretreatment chamber with heat insulation function and a constant temperature and humidity machine. The constant temperature and humidity machine is used to regulate the humidity of the air in the pretreatment chamber. The air delivery module is equipped with a variable frequency fan, which is used to adjust the mass flow rate of dry air. The air reheating module is equipped with an electric heater, which is used to regulate the temperature of the air.

3. The multi-parameter adjustable experimental testing platform for a tumble dryer according to claim 2, characterized in that, The air handling subsystem includes a humidity control module, which is used to calculate the deviation between the temperature and humidity in the pretreatment room collected in real time by the monitoring layer and the preset target temperature and humidity, and to adjust the constant temperature and humidity machine based on the deviation so that the humidity of the air in the pretreatment room reaches the target humidity.

4. The multi-parameter adjustable experimental testing platform for a tumble dryer according to claim 2, characterized in that, The air handling subsystem includes a frequency control module, used to adjust the frequency of the inverter of the variable frequency fan according to the target dry air mass flow rate using a mapping model; the mapping model is obtained by adjusting the frequency of the inverter of the variable frequency fan, and the monitoring layer monitors the airflow speed in real time to obtain the frequency-wind speed mapping relationship; the measured wind speed is linearly converted into dry air mass flow rate using the fan characteristic parameters and aerodynamic correlation logic to obtain the wind speed-dry air mass flow rate mapping relationship; the frequency-wind speed mapping relationship and the wind speed-dry air mass flow rate mapping relationship are combined to obtain the mapping model.

5. The multi-parameter adjustable experimental testing platform for a tumble dryer according to claim 2, characterized in that, The air handling subsystem includes a temperature control module, which calculates the deviation between the temperature of the airflow collected in real time by the monitoring layer and the preset target airflow temperature, and performs PID control on the electric heater based on the deviation so that the temperature of the airflow reaches the target airflow temperature.

6. The multi-parameter adjustable experimental testing platform for a tumble dryer according to claim 1, characterized in that, The roller motion subsystem controls the roller section to perform a four-stage bidirectional alternating sequential cyclic motion via an external frequency converter. The four-stage bidirectional alternating sequential cyclic motion includes: a counterclockwise rotation phase, a first stop and hold phase, a clockwise rotation phase, and a second stop and hold phase. The running time of both the counterclockwise and clockwise rotation phases includes the motor rotation time and the inertia compensation pause time. The inertia compensation pause time is used to asymmetrically align the timing of the motor control commands with the timing of the roller's physical motion.

7. The multi-parameter adjustable experimental testing platform for a tumble dryer according to claim 1, characterized in that, The air ducts within the air handling section and the air duct between the air handling section and the roller section are constructed from one or more of the following: high-temperature resistant silicone vulcanized air ducts, stainless steel air ducts, and galvanized air ducts; the connection nodes of each air duct are sealed with flanges, clamps, sealant, and aluminum foil tape, and the outside of the air ducts is covered with thermal insulation material.

8. The multi-parameter adjustable experimental testing platform for a tumble dryer according to claim 1, characterized in that, The monitoring layer supports both a fixed-parameter configuration mode and a phased-parameter configuration mode for the entire process of automated control of the experiment. The fully automated control process includes load mass termination conditions and drying time termination conditions. The load mass termination condition means that the experiment terminates when the fabric load reaches a preset target load mass. The drying time termination condition means that the experiment terminates when the fabric load drying time reaches a preset target drying time. The fixed-parameter configuration mode involves setting a set of experimental parameters before the experiment, including thermodynamic parameters, drum control parameters, and termination conditions. During the experiment, the air handling subsystem follows the set parameters. The thermodynamic parameters control the air handling section, and the drum motion subsystem controls the drum section according to the set drum control parameters until the set termination condition is reached. The phased parameter configuration mode refers to setting multiple sets of experimental parameters before the experiment. Each set of experimental parameters includes thermodynamic parameters, drum control parameters, and termination conditions. During the experiment, the air handling subsystem first controls the air handling section according to the thermodynamic parameters in the first set of experimental parameters, and then controls the drum section according to the drum control parameters in the first set of experimental parameters until the termination condition in the first set of experimental parameters is reached. After completion, the experiment is carried out based on the next set of experimental parameters until all sets of experimental parameters are completed.

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