Aging test device considering greenhouse film stress and test method thereof

Abstract

The invention belongs to the field of greenhouse film aging test methods, and relates to an aging test device considering greenhouse film stress and a test method thereof.The aging test device comprises an upper environment box, a lower environment box, a test observation box and a control panel which are arranged on a main frame, a support plate and an observation platform are arranged in the test observation box, and a greenhouse film fixing frame is arranged above the support plate and the observation platform; an arc-shaped arch frame is arranged in the greenhouse film fixing frame, a flexible film pressing rope is arranged at the top of the greenhouse film fixing frame, and the two ends of the greenhouse film fixing frame are connected with a rotary tensioning device at an end plate of the greenhouse film fixing frame and a force sensor at an end plate of the other opposite end of the greenhouse film fixing frame respectively. Tension needed in the test process can be accurately adjusted and applied before the test is started through the rotary tensioning device and the force sensor, if an electric tensioning actuator is used, greenhouse film stress can be compensated and calibrated in real time in the test process, and other environmental parameters such as temperature, humidity and ultraviolet light intensity can be further adjusted. And a multi-environmental factor interaction test of the greenhouse film in a natural curved surface and stress state is realized.

Description

Technical Field

[0001] This invention belongs to the field of greenhouse film aging test methods, specifically relating to an aging test device and test method that takes into account the stress on the greenhouse film. Background Technology

[0002] Greenhouse film is a key material in facility agriculture, and its durability and performance stability directly affect the ability to regulate the crop growth environment and production efficiency. In practical applications, greenhouse film must withstand the combined effects of complex environmental factors such as high temperature, high humidity, mechanical tension, and ultraviolet radiation for extended periods. Especially under the influence of wind loads and snow pressure, the film is continuously under tensile stress, accelerating material fatigue and aging. These factors accelerate the aging process of the film, leading to a significant decline in its physical and optical properties, such as discoloration, embrittlement, stress crack propagation, and reduced light transmittance. This not only affects the internal lighting conditions and temperature control within the greenhouse, shortening the lifespan of the film and increasing agricultural production costs, but may also cause localized damage due to stress concentration, adversely affecting crop growth and even leading to problems such as frost damage and the proliferation of pests and diseases, posing a serious threat to facility agriculture production.

[0003] Currently, most testing methods for evaluating the aging performance of greenhouse films have limitations and cannot fully simulate the multi-physics coupled environment of actual applications. Commonly used aging test methods for greenhouse films include natural exposure, accelerated aging, and damp heat aging. Natural exposure is time-consuming and costly, accelerated aging focuses only on ultraviolet radiation testing, and damp heat aging emphasizes aging tests under constant temperature and humidity conditions. These methods neglect the interaction between factors such as high temperature, high humidity, mechanical tension, and ultraviolet radiation. The results obtained from these single-factor testing methods deviate significantly from the aging conditions in actual applications, making it impossible to accurately predict the durability and performance changes of greenhouse films under real-world service conditions, and thus failing to meet the demands of facility agriculture for high-performance and long-life greenhouse films.

[0004] Therefore, it is necessary to develop an aging test method that takes into account the stress on the greenhouse film, so as to effectively solve the research problem that traditional test methods cannot fully simulate the real environment. This has become the focus of the inventor's research. Summary of the Invention

[0005] To overcome the problems of existing greenhouse film aging test methods in terms of environmental simulation, such as limited test conditions, low accuracy, unsatisfactory controllability of test conditions, and difficulty in conducting multi-factor interaction tests including greenhouse film stress elements, this invention provides an aging test device and method that considers greenhouse film stress. The device includes an upper environmental chamber, a lower environmental chamber, a test observation chamber, and a control panel, all mounted on a main frame. A support plate and an observation platform are provided inside the test observation chamber. A greenhouse film fixing frame is installed above the support plate and observation platform. An arc-shaped arch frame is installed inside the greenhouse film fixing frame, and a top arc-shaped arch frame is provided at the top of the arch frame. A flexible film-pressing rope with an external silicone sleeve is installed. One end of the flexible film-pressing rope is connected to a rotating tensioning device at the end plate of the greenhouse film fixing frame, and the other end is connected to a force sensor at the opposite end plate of the greenhouse film fixing frame. This allows the greenhouse film to be subjected to force in a natural curved state. The tension during the test can be precisely adjusted and fixed before the test begins through the rotating tensioning device and the force sensor. Furthermore, other environmental parameters such as temperature, humidity, and ultraviolet light intensity can be adjusted to achieve multiple environmental factor interaction tests on the greenhouse film under natural curved surface and stress state. This allows for accurate simulation and evaluation of the aging performance of the greenhouse film.

[0006] The present invention first provides an aging test device considering the stress of greenhouse film, including a main frame and an upper environmental chamber, a test observation chamber and a lower environmental chamber set on the main frame. The bottom of the upper environmental chamber is open, the top of the lower environmental chamber is open, and the top and bottom of the test observation chamber are open. The upper environmental chamber, the test observation chamber and the lower environmental chamber cooperate with each other and can be sealed. The device includes a control module, as well as a sensing module, a temperature regulation module and an ultraviolet regulation module inside the environmental chamber, and a humidity regulation module that communicates with the inside of the environmental chamber. The front of the test observation box is equipped with an embedded door, while the other three sides are UV-proof vacuum glass windows, which can effectively block external light and ensure that the lighting conditions during the test are basically determined by the UV adjustment module. A horizontal observation platform is detachably fixed inside the test observation box, and a support plate with through holes is fixed at the bottom. The observation platform can be fixed in a variety of ways, such as being supported and fixed on a grid plate inside the test observation box. The cross-sectional dimension of the observation platform should be smaller than the cross-sectional dimension of the test observation box to avoid excessive impact on the internal gas flow. A rectangular film fixing frame is set on the observation platform and support plate. Inside the film fixing frame, there are arc-shaped arches symmetrically arranged along both sides of the film fixing frame. The film is supported above the arc-shaped arches and fixed below the flexible film-pressing rope to ensure that the film maintains a natural curved surface under stress. The top of the arc-shaped arches is equipped with a flexible film-pressing rope. One end of the flexible film-pressing rope is connected to a rotating tensioning device at the end plate of the film fixing frame, and the other end is connected to a force sensor fixedly connected to the film fixing frame at the other end plate of the rotating tensioning device. The end of the flexible film-pressing rope is connected to the force-receiving end of the force sensor through a clamp, which can precisely adjust the film tension so that the film is subjected to force in a natural curved surface state. The force sensor is connected to and wiredly connected to the control module.

[0007] This invention enables the simultaneous application of one or more of the following to greenhouse films under natural curved surfaces and stress conditions: high temperature, high humidity, and ultraviolet radiation. This achieves multi-physical field coupling in a real environment, unlike traditional single-factor aging tests. Through integrated operation, it achieves multi-environment synergistic loading, significantly improving test efficiency and simulation realism. It can be used for long-term continuous testing and is suitable for rapid evaluation of material durability under complex working conditions.

[0008] The control module comprises an upper environmental chamber control panel, a lower environmental chamber control panel, and a central processing unit integrated within the upper and lower environmental chamber control panels, all mounted on the main frame. The sensing module includes a temperature sensor, a humidity sensor, and an ultraviolet sensor fixedly installed inside the environmental chamber. A fan, a temperature regulation module, an ultraviolet regulation module, a force sensor, and a sensing module installed inside the environmental chamber, as well as a humidity regulation module connected to the interior of the environmental chamber, are electrically connected to the upper and lower environmental chamber control panels. These modules are used to control the operation of the fan, temperature regulation module, humidity regulation module, ultraviolet regulation module, and force sensor, and to receive signals from the sensing modules and force sensor. The positions of the sensing modules, fan, and each regulation module can be flexibly adjusted according to experimental requirements and are not specifically limited.

[0009] Preferably, the rotary tensioning device is a rotary tensioning knob, which is threaded to the end plate of one end of the film fixing frame. When rotated, it can retract the end of the flexible film pressing rope wrapped on it. The upper environmental box control panel and the lower environmental box control panel have built-in PID industrial general tension control algorithm. Users can set the target tension value. The system automatically prompts "increase / decrease" the rotary tension force by comparing the sensor feedback value with the set value in real time.

[0010] Alternatively, the rotary tensioning device can be an electric tensioning actuator, which includes a stepper motor, a reduction gear set, and a winding reel. The electric tensioning actuator is fixed to the end plate of the film fixing frame. The end of the stepper motor is sequentially connected to the reduction gear set and the winding reel. The reduction gear set amplifies the torque of the stepper motor and applies it to the winding reel. The end of the flexible film pressing rope is fixedly wound around the winding reel of the electric tensioning actuator. The control module integrates a PID industrial general tension control algorithm, and a target tension value is set on the control module. The tension of the greenhouse film is monitored in real time by a force sensor, and the feedback value is compared with the set value. When the tension value is lower than the set value due to reasons such as film loosening, creep, or temperature changes, the control module sends a command to the electric tension actuator to drive the stepper motor to rotate and tighten the flexible film-pressing rope, so that the tension tends to the target value. When the tension is greater than the set value, the control module sends a command to the electric tension actuator to drive the stepper motor to rotate and release the flexible film-pressing rope, so that the tension tends to the target value, thereby realizing fully automatic, high-precision closed-loop control and real-time compensation of tension.

[0011] The electric tensioning actuator control system includes a power module, a force sensor, a control module, a judgment module, and a stepper motor. The power module supplies power to the force sensor, control module (i.e., upper environmental box control panel and lower environmental box control panel) and stepper motor. The power modules for the force sensor and stepper motor are integrated inside the module, while the control module is powered by an external power supply. After the force sensor acquires the monitored tension, it outputs the monitored tension signal to the control module; The control module takes a set tension value as input and receives a monitored tension signal, and outputs the set tension value and the monitored tension signal to the judgment module. The judgment module is integrated with the control module and shares the same power supply module with the control module. It inputs the set tension value and the monitored tension signal to the control module. When the monitored tension is greater than the set tension, it outputs a tension reduction signal to the stepper motor. When the monitored tension is less than the set tension, it outputs a tension increase signal to the stepper motor. After the stepper motor receives the tension reduction signal or the tension increase signal, it rotates in the corresponding direction and acts on the downstream reduction gear set and winding wheel, thereby tightening or releasing the flexible film pressing rope and changing the stress on the greenhouse film. After the stress on the greenhouse film changes, a new monitoring tension signal is obtained by the force sensor. The force sensor then inputs the new monitoring tension signal back into the control module, and the above process is repeated cyclically to judge and adjust the tension.

[0012] Preferably, a fan, a temperature control module, an ultraviolet control module, and a sensing module are installed inside the upper and lower environmental boxes. The humidity control module is connected to the upper and lower environmental boxes. The force sensor is correspondingly installed with the film fixing frame. Each of the fan, temperature control module, humidity control module, ultraviolet control module, sensing module, and force sensor is electrically connected to one of the control panels of the upper and lower environmental boxes according to its relative position (if the position is relatively upward, it is connected to the upper environmental box control panel; if it is relatively downward, it is connected to the lower environmental box control panel; if it is relatively central, it can be selected from either one). As a further preferred embodiment, a temperature control module and a sensing module are installed in both the upper and lower environmental boxes.

[0013] The humidity control module includes a water tank mounted on the main frame, a humidifier mounted on the main frame, and a water purifier. The downstream of the water tank is connected to the humidifier. The upper and / or lower environmental chambers have adapter interfaces on their walls for connecting to the pipes connected to the humidifier outlet. The water purifier's outlet is connected to the water tank. The water purifier purifies the incoming water from the water supply system and then sends it into the water tank. The humidifier draws water from the water tank, atomizes the water in the humidifier, and sends it through pipes into the assembled upper environmental chamber, lower environmental chamber, and test observation chamber. The water mist circulates under the action of the fans inside the chambers to regulate humidity. A humidity sensor can monitor humidity data in real time. The power of the humidifier is controlled by an industrial general PID algorithm to ensure that humidity fluctuations are ≤3% RH, thereby solving the problems of excessive local humidity and equipment corrosion caused by traditional spraying.

[0014] The temperature control module consists of compressors installed in the upper and lower environmental chambers.

[0015] The ultraviolet adjustment module includes an ultraviolet lamp and an integrated telescopic rod. The integrated telescopic rod is detachably fixed to the inside of the two opposing ultraviolet-proof vacuum glass windows of the test observation box. The integrated telescopic rod consists of glass suction cups at both ends, telescopic knobs inside the glass suction cups, and a telescopic rod in the middle. It is physically adsorbed onto the surface of the ultraviolet-proof vacuum glass window through the glass suction cups, which breaks through the damage to the test observation box structure caused by traditional fixing methods (such as bolt fixing and adhesive fixing). The installation position can be flexibly adjusted and reused, adapting to aging tests in multiple scenarios. It is especially suitable for aging tests in multiple scenarios that require frequent changes in test layout, while avoiding damage to the airtightness of the box. Integrated telescopic poles are known products in existing technology and can be purchased directly. For example, the Future Style telescopic pole (model 100-170) purchased from the Future Style JD.com flagship store features an inner and outer sleeve structure. The axial length can be adjusted from 30 to 50 cm using a telescopic knob. This integrated telescopic pole has flexible adjustment functions, allowing for length and position adjustments according to different test requirements. It enables flexible adjustment and reuse of the installation position. It integrates telescopic adjustment, angle fine-tuning, and rigid locking functions, solving the problem of loosening after adjustment of traditional telescopic poles. It can accurately control the distance between the ultraviolet lamp tube and the greenhouse film, ensuring uniform radiation intensity. By locking the integrated telescopic pole, the deviation of the ultraviolet radiation distance can be controlled to ≤1 mm under vibration environment. A C-shaped buckle is installed at the bottom of the integrated telescopic rod. The ultraviolet lamp is detachably fixed to the integrated telescopic rod via the C-shaped buckle, which facilitates the quick installation and removal of the ultraviolet lamp and ensures the stability of the ultraviolet lamp during the test, effectively preventing the ultraviolet lamp from loosening or falling off. The C-shaped buckle is made of elastic material and fits onto the rod body of the integrated telescopic rod. The ultraviolet lamp is fixed in the opening of the C-shaped buckle. The outer frame of the test observation box has a wire hole. After the wire is threaded, a sealing ring is set around the wire hole or it is sealed with sealant. The connection wire of the ultraviolet lamp is exited at the top of the integrated telescopic rod. The connection wires of the ultraviolet lamp, fan, temperature control module, sensor module and force sensor are threaded through the wire hole and electrically connected to the corresponding control module. The C-shaped buckle can slide along the integrated telescopic rod. The C-shaped buckle is provided with corresponding screw holes. The C-shaped buckles are connected and fixed with bolts (not shown in the figure), realizing dynamic adjustment, flexible installation and precise positioning. The position and number of ultraviolet lamps can be quickly adjusted according to the test requirements.

[0016] Furthermore, the power cord of the ultraviolet lamp is wrapped with three layers of material from the inside out, including an inner fluororubber insulation layer, a middle tin-plated copper wire braided shielding layer, and an outer polytetrafluoroethylene anti-aging sheath. It is connected through the wiring hole on the test observation box, which effectively extends the service life and ensures test safety, ensuring the smooth progress of the test process.

[0017] In a specific embodiment of the present invention, the force sensor has a range of 0~200 N, an accuracy of ±0.3%FS, and an output signal of 4~20 mA digital signal, and can be purchased from Nanjing Chiyuan System Engineering Co., Ltd. (model CYH-3X-B).

[0018] Furthermore, the flexible pressure rope is covered with a silicone sleeve to prevent it from abrading the surface of the greenhouse film.

[0019] The recessed door features a double-door design, and the door can be secured in the middle with a sealing strip. This double-door design helps to better ensure the airtightness of the cabinet. Optionally, multiple observation platforms can be set up inside the test observation box. Each observation platform can be independently equipped with a film fixing frame and the film can be fixed to achieve multiple sets of comparative tests. In a specific embodiment of the present invention, one or more observation platforms are set up.

[0020] The bottom surface of the upper environmental chamber, the top surface of the lower environmental chamber, and the upper and lower ends of the test observation chamber are all equipped with sealing components (such as rubber sealing strips or silicone sealing rings), which together form a sealed overall structure.

[0021] The greenhouse film fixing frame can be made of various materials as needed, as long as it does not significantly affect the test. In a specific embodiment of the present invention, the greenhouse film fixing frame is made of aluminum alloy.

[0022] In a specific embodiment of the present invention, the flexible pressure rope is made of high-strength polyester fiber.

[0023] The five inner walls of the upper and lower environmental chambers are all covered with insulation material (such as polyurethane foam, rock wool, etc.), and waterproof aluminum foil is fixed to the surface of the insulation material (fixed by conventional methods, such as bonding with high-temperature resistant adhesive). The environmental chambers have built-in fans and compressors (the fans can be installed in the upper and / or lower environmental chambers as needed; compressors are installed inside both the upper and lower environmental chambers). The walls of the environmental chambers have interfaces that connect to the downstream of the humidifier. The interfaces are sealed with seals (such as rubber sealing strips or silicone sealing rings). The compressor can cool or heat. The fan is used to continuously circulate air during the test to ensure that the temperature distribution inside the test observation chamber is uniform and constant, effectively preventing abnormal aging of the greenhouse film material or fire caused by local overheating, thereby improving test safety and temperature control accuracy. The humidifier regulates the humidity inside the environmental chamber to create a continuous set environment, thereby achieving the regulation and control of the temperature and humidity inside the assembled and sealed upper and lower environmental chambers and the test observation chamber.

[0024] The present invention further provides an aging test method considering the stress on the greenhouse film, which is carried out using the above-mentioned test apparatus and includes: (1) Cut the greenhouse film sample to be tested into the required size for the test, clean the surface to remove impurities and contaminants, and then balance it in a standard environment (general conditions of standard environment: 23±2℃, relative humidity: 45%~55%) to adapt the greenhouse film to the test environment and reduce the influence of environmental factors. Record the initial parameters of the greenhouse film sample to provide a comparison benchmark for subsequent aging tests. Lay the greenhouse film sample flat on the double-arc arch frame (i.e., the arch frame with a shape symmetrical along the inside of the greenhouse film fixing frame) of the greenhouse film fixing frame, and fix the greenhouse film with a flexible film pressing rope. One end of the flexible film pressing rope is fixed to the rotating tensioning device on the end plate of the greenhouse film fixing frame, and the other end is fixed to the force sensor. After setting the target tension, adjust the rotating tensioning device according to the current value displayed on the control panel until the tension is adjusted to the set value to ensure that the stress is constant throughout the test. (2) Place the integrated telescopic rod in the corresponding installation position inside the test observation box. First, attach the glass suction cup at one end of the integrated telescopic rod to the corresponding position. Then, extend the integrated telescopic rod by using the telescopic knob and attach the glass suction cup at the other end to the corresponding UV-proof vacuum glass window. The length of the integrated telescopic rod corresponds to the inside of the test observation box and is fixed by the glass suction cup. Lock the integrated telescopic rod to ensure its stability during the test. Install the corresponding number of C-shaped buckles and ultraviolet lamps on the telescopic rod as needed, so that the ultraviolet lamps and C-shaped buckles fit tightly together. Connect the power cord of the ultraviolet lamp to the power system after passing it through the wire hole. (3) Connect the water purifier to the water supply system to ensure the water quality is pure and avoid scale blockage of the test device due to water quality problems, which would affect the test results; then close the embedded door of the test observation box and seal the middle of the embedded door and the junction of the upper environmental box, the test observation box and the lower environmental box; turn on the control module and turn on one or more of the corresponding temperature adjustment module, humidity adjustment module and ultraviolet adjustment module until the space inside the test observation box, the upper environmental box and the lower environmental box reaches a stable test environment; (4) Monitor and record the performance indicators of the greenhouse film (such as temperature, humidity, ultraviolet intensity, force) through the control panel of the upper environmental box and the control panel of the lower environmental box. After the test, analyze the collected parameters and evaluate the aging degree of the greenhouse film.

[0025] Based on the initial parameters and experimentally collected parameters, we can gain a detailed understanding of the aging patterns of greenhouse films under one or more combined effects of high temperature, high humidity, mechanical tension, and ultraviolet radiation, providing a scientific basis for the performance evaluation and lifespan of greenhouse films.

[0026] As a preferred option, in step (1), the surface of the greenhouse film sample is cleaned with anhydrous ethanol to remove any possible impurities and contaminants, thereby improving the accuracy of the test results; the sample is equilibrated in a standard environment for at least 24 hours to allow it to adapt to the test environment and reduce the impact of environmental factors on the test results; the initial thickness, weight, and optical performance parameters of the greenhouse film sample are recorded to provide a benchmark for subsequent aging tests; the greenhouse film fixing frame is a rectangular structure with symmetrical arc-shaped arches on both sides inside, used to simulate the curved tension state of the greenhouse film in actual agricultural facilities; the pressure rope spans the top of the arch and is gradually tensioned or released by rotating the tensioning device, which can preset and fix the stress on the greenhouse film during the test before the test begins, simulating the continuous stress state of the greenhouse film; the force sensor collects the tension force data in real time and displays the current stress value in real time through the environmental chamber control panel, ensuring that the stress on the greenhouse film is constant and traceable during the test, and improving the consistency between the test conditions and the actual service state; In step (2), an anti-ultraviolet vacuum glass window is used, which can effectively block external light and ensure that the lighting conditions of the test environment during the test are basically completely controlled by the internal light source, so that external light cannot enter the interior; Before placing the integrated telescopic rod, clean the inner surface of the UV-resistant vacuum glass window of the test observation box to ensure that the surface is dry and free of any adhering substances, so as to provide good contact conditions for the physical adsorption of the glass suction cup; the integrated telescopic rod extends along the length of the test observation box and is perpendicular to the UV-resistant vacuum glass window it is adsorbing; after installing the UV lamp, ensure that the electrical connection of the UV lamp is reliably connected to the power cord. The initial parameters in step (1) are the thickness, weight, and optical performance parameters of the greenhouse film; the parameters monitored in real time in step (4) include the test environment parameters and the tension force on the greenhouse film. The environmental parameters include temperature, humidity, and ultraviolet intensity. The test collection parameters include the environmental parameters as well as the tension force, thickness, weight, and optical performance parameters of the greenhouse film. The optical performance parameters include surface energy, transmittance, dripping, and light conversion efficiency. The tension force, temperature, humidity, and ultraviolet intensity of the greenhouse film in the test collection parameters are monitored in real time through the control panel of the upper environmental box and / or the control panel of the lower environmental box. The thickness, weight, and optical performance parameters are stopped every 1000 h, the greenhouse film is removed, and the data is tested and recorded once. Then the greenhouse film is put back, the assembly device is reassembled, and the operation continues.

[0027] Compared with the prior art, the present invention has achieved the following beneficial effects: (1) This invention provides a new method for simulating the aging of greenhouse film. Through a dedicated test device, it can simultaneously simulate the coupled effects of multiple environmental factors such as mechanical tension, high temperature, high humidity and ultraviolet radiation. In particular, the combined effect of mechanical tension and other factors effectively solves the problem that traditional test methods cannot fully simulate the real environment, and provides more accurate and realistic test conditions for studying the aging behavior of greenhouse film in practical applications. (2) The test device is innovatively designed, using an integrated telescopic rod and glass suction cup combination to achieve non-destructive installation and flexible adjustment. This not only protects the structural integrity of the test chamber, but also greatly improves the versatility and reusability of the device, making it particularly suitable for aging test needs in multiple scenarios and under multiple conditions. (3) The environmental control system of the device can accurately adjust parameters such as temperature, humidity, and mechanical tension, and ensure water purity through a water purifier connection to avoid scale blockage, thereby improving the stability of the experiment and the reliability of the results. (4) Through reasonable power cord design and three-layer material wrapping, the safety and durability of electrical connection are enhanced, the safety of the test process is guaranteed, the service life of the equipment is extended, and the operation and maintenance are also convenient, thus improving the overall test efficiency. (5) This invention innovatively introduces an automatic force monitoring and compensation closed-loop control system. Through the coordinated work of the electric tension actuator and the force sensor, the tension of the greenhouse film can be sensed and automatically adjusted in real time, effectively overcoming the stress relaxation problem caused by material creep and changes in ambient temperature. This ensures the extreme stability and consistency of the stress state of the greenhouse film throughout the long-term aging test, greatly improving the accuracy and reliability of the test data, which is impossible to achieve by manual adjustment.

[0028] This invention provides an aging test device and method that considers the stress on greenhouse films. By constructing an accelerated aging environment coupled with four fields—mechanical force, high temperature, high humidity, and ultraviolet radiation—it achieves a realistic reproduction of the actual service conditions of greenhouse films. Using this device, the performance evolution of greenhouse films under the synergistic effects of multiple environmental factors can be obtained in a short time. The reliability of the accelerated model can be verified by comparing the results with outdoor natural exposure tests. Simultaneously, based on real-time monitoring data of key indicators such as film thickness, light transmittance, and mechanical properties, a correlation model between environmental parameters and aging behavior is established, revealing the multi-factor synergistic aging mechanism and providing quantitative evidence for evaluating the durability of greenhouse films. For greenhouse films of different materials or structures, simultaneous comparative tests can be conducted on the same test platform to quickly obtain the differences in anti-aging performance of various types of films. The aging mechanism can be analyzed by combining material composition, microstructure evolution, and macroscopic aging phenomena. Furthermore, by independently adjusting the temperature, humidity, ultraviolet intensity, and mechanical force levels, different climate zones or extreme weather scenarios in my country can be flexibly simulated to assess the regional applicability and lifespan limits of greenhouse films. This method overcomes the limitations of traditional single-factor aging tests, which deviate significantly from real-world conditions, and provides a scientific, efficient, and repeatable technical means for optimizing greenhouse film formulations, developing new products, grading performance, and predicting service life. Attached Figure Description

[0029] Figure 1 This is a three-dimensional structural diagram of the aging test apparatus of the present invention; Figure 2 for Figure 1 A schematic diagram of the rear-facing three-dimensional structure; Figure 3 This is a front structural diagram of the aging test apparatus of the present invention; Figure 4 This is a schematic diagram of the rear structure of the aging test apparatus of the present invention; Figure 5 This is a three-dimensional structural diagram of the experimental observation box; Figure 6 for Figure 5 A schematic diagram of the rear-facing three-dimensional structure; Figure 7 This is a schematic diagram of the front structure of the experimental observation box; Figure 8This is a schematic diagram of the three-dimensional structure of the experimental observation box from another direction; Figure 9 This is a schematic diagram of the stress structure of the greenhouse film in embodiments 1 and 2; Figure 10 This is a schematic diagram of the stress structure of the greenhouse film in embodiment 3; Figure 11 This is a schematic diagram of the circuit signal transmission block diagram of the electric tensioning actuator control system.

[0030] The components are as follows: 1 is the main frame, 2 is the water purifier, 3 is the water tank, 4 is the experimental observation box, 5 is the upper environmental box control panel, 6 is the lower environmental box control panel, 7 is the humidifier, 8 is the upper environmental box, 9 is the lower environmental box, 10 is the embedded box door, 11 is the UV-resistant vacuum glass window, 12 is the wire hole, 13 is the observation platform, 14 is the support plate, 15 is the greenhouse film, 16 is the greenhouse film fixing frame, 17 is the arc-shaped arch frame, 18 is the flexible film pressing rope, 19 is the rotary tension knob, 20 is the force sensor, 21 is the integrated telescopic rod, 22 is the C-shaped buckle, 23 is the ultraviolet lamp tube, 24 is the glass suction cup, 25 is the telescopic knob, 26 is the telescopic rod, 27 is the stepper motor, 28 is the reduction gear set, and 29 is the winding reel. Detailed Implementation

[0031] The technical solution of the present invention will be further described below with reference to specific embodiments. These embodiments are only used to illustrate the technical solution of the present invention in more detail and should not be construed as limiting the scope of protection of the present invention.

[0032] Device Example 1: An aging test device considering the stress on the greenhouse film like Figure 1-8 As shown, the aging test device considering the stress on the greenhouse film includes a main frame 1 and an upper environmental chamber 8, a test observation chamber 4, and a lower environmental chamber 9 mounted on the main frame 1. The upper environmental chamber 8 has an open bottom, the lower environmental chamber 9 has an open top, and the test observation chamber 4 has open tops and bottoms. The upper environmental chamber 8, the test observation chamber 4, and the lower environmental chamber 9 cooperate with each other and can be sealed together. In addition, it includes a control module, a sensing module, a temperature regulation module, an ultraviolet regulation module inside the environmental chamber, and a humidity regulation module connected to the interior of the environmental chamber.

[0033] The front of the test observation box 4 is equipped with an embedded door 10, and the other three sides are UV-proof vacuum glass windows 11, which can effectively block external light and ensure that the lighting conditions during the test are basically determined by the UV adjustment module. The test observation box 4 is equipped with a detachable horizontal observation platform 13, and a support plate 14 with through holes is fixed at the bottom. The observation platform 13 is supported and fixed on the grid plate inside the test observation box 4. like Figure 9As shown, both the observation platform 13 and the support plate 14 are equipped with rectangular film fixing frames 16. Inside the film fixing frames 16, there are symmetrical arc-shaped arches 17. The top of the arc-shaped arches 17 is equipped with a flexible film-pressing rope 18. One end of the flexible film-pressing rope 18 is connected to a rotating tension knob 19 at the end plate of the film fixing frame 16. The rotating tension knob 19 is threadedly connected to the end plate of one end of the film fixing frame 16. When it rotates, it can retract or expand the end of the flexible film-pressing rope 18 wound on it. The flexible film-pressing rope 18 has another... A force sensor 20, which is fixedly connected to the film fixing frame 16, is connected to the end plate of the tension knob 19, which rotates relative to the film fixing frame 16 at one end. The end of the flexible film pressing rope 18 is connected to the force receiving end of the force sensor 20 through a clamp, which can precisely adjust the tension of the film 15 so that the film 15 is subjected to force in a natural curved state. The force sensor 20 is connected to and wired to the control module. The film 15 is set above the arc-shaped arch frame 17 and below the flexible film pressing rope 18 to ensure that the film 15 is in a natural curved state under force.

[0034] This device enables the simultaneous application of one or more of the following to the greenhouse film 15 under natural curved surface and stress conditions: high temperature, high humidity, and ultraviolet radiation. This achieves multi-physical field coupling in a real environment, which is different from traditional single-factor aging tests. Through integrated operation, it achieves multi-environment synergistic loading, significantly improving test efficiency and simulation realism. It can conduct tests continuously for a long time and is suitable for rapid evaluation of material durability under complex working conditions.

[0035] The control module consists of an upper environmental chamber control panel 5 and a lower environmental chamber control panel 6 mounted on the main frame 1, as well as a central processing unit integrated into the upper environmental chamber control panel 5 and the lower environmental chamber control panel 6. The sensing module includes a temperature sensor, a humidity sensor, and an ultraviolet sensor fixedly installed inside the environmental chamber. A fan, a temperature regulation module, an ultraviolet regulation module, a force sensor 20, and a sensing module installed inside the environmental chamber, as well as a humidity regulation module communicating with the interior of the environmental chamber, are electrically connected to the upper environmental chamber control panel 5 and the lower environmental chamber control panel 6. These components are used to control the operation of the fan, temperature regulation module, humidity regulation module, ultraviolet regulation module, and force sensor 20, and to receive signals from the sensing module and the force sensor 20. The upper environmental box control panel 5 and the lower environmental box control panel 6 are equipped with a built-in PID industrial general tension control algorithm. Users can set the target tension value. The system automatically prompts the rotation direction of the tension knob 19 by comparing the sensor feedback value with the set value in real time. When the sensor feedback value is less than the set value, it prompts to increase; when it is greater than the set value, it prompts to decrease. The "increase / decrease" signal is output to the upper environmental box control panel 5 and the lower environmental box control panel 6 for display.

[0036] A fan, a temperature control module, an ultraviolet (UV) control module, and a sensor module are installed inside the upper environmental chamber 8 and the lower environmental chamber 9. The humidity control module is connected to the upper environmental chamber 8 and the lower environmental chamber 9. The force sensor 20 is correspondingly installed with the greenhouse film fixing frame 16. Each of the fan, temperature control module, humidity control module, UV control module, sensor module, and force sensor 20 is electrically connected to one of the upper environmental chamber control panel 5 and the lower environmental chamber control panel 6 according to its relative position (if the position is relatively upward, it is connected to the upper environmental chamber control panel 5; if it is relatively downward, it is connected to the lower environmental chamber control panel 6; if it is relatively central, it can be either one). Both the upper environmental chamber 8 and the lower environmental chamber 9 are equipped with a temperature control module and a sensor module (that is, two sets of temperature control modules and sensor modules are installed in the upper environmental chamber 8 and the lower environmental chamber 9, and each is electrically connected to the upper environmental chamber control panel 5 and the lower environmental chamber control panel 6 respectively).

[0037] The humidity control module includes a water tank 3 installed on the main frame 1, a humidifier 7 installed on the main frame 1, and a water purifier 2. The downstream of the water tank 3 is connected to the humidifier 7. The upper environmental chamber 8 and the lower environmental chamber 9 have adapter interfaces on their walls for connecting to the pipes connected to the outlet of the humidifier 7. The outlet of the water purifier 2 is connected to the water tank 3. The water purifier 2 purifies the water from the water supply system and then sends it into the water tank 3. The humidifier 7 takes water from the water tank 3. The water is atomized in the humidifier 7 and then sent through pipes into the assembled upper environmental chamber 8, lower environmental chamber 9, and test observation chamber 4. The water mist circulates under the action of the fan inside the chamber to regulate the humidity. The humidity sensor can monitor the humidity data in real time. The power of the humidifier is controlled by an industrial general PID algorithm to ensure that the humidity fluctuation is ≤3%RH, thereby solving the problems of excessive local humidity and equipment corrosion caused by traditional spraying.

[0038] The temperature regulation module is a compressor installed in the upper environmental chamber 8 and the lower environmental chamber 9.

[0039] The ultraviolet adjustment module includes an ultraviolet lamp 23 and an integrated telescopic rod 21. The integrated telescopic rod 21 is detachably fixed to the inner side of the two opposite ultraviolet-proof vacuum glass windows 11 of the test observation box 4. The integrated telescopic rod 21 consists of glass suction cups 24 at both ends, telescopic knobs 25 on the inner side of the glass suction cups 24, and a telescopic rod 26 in the middle. It is physically adsorbed to the surface of the ultraviolet-proof vacuum glass window 11 by the glass suction cups 24, which breaks through the destruction of the test observation box 4 body structure by traditional fixing methods (such as bolt fixing and adhesive fixing). The installation position can be flexibly adjusted and reused, which is suitable for aging tests in multiple scenarios. It is especially suitable for aging tests in multiple scenarios that require frequent changes in test layout, while avoiding damage to the airtightness of the box.

[0040] The integrated telescopic rod 21 is a known product in the prior art. In this embodiment, it is a telescopic rod purchased from the Future Style JD.com self-operated flagship store, model number 100-170. The integrated telescopic rod 21 has an inner and outer sleeve structure. The axial length can be adjusted from 30 to 50 cm using the telescopic knob 25. The integrated telescopic rod 21 has a flexible adjustment function, which can adjust the length and position according to different test requirements, realize flexible adjustment of the installation position and reuse. It integrates telescopic adjustment, angle fine adjustment and rigid locking functions, solves the problem of easy loosening after adjustment of traditional telescopic rods, and can accurately control the distance between the ultraviolet lamp tube 23 and the greenhouse film 15 to ensure uniform radiation intensity.

[0041] A C-shaped buckle 22 is provided at the bottom of the integrated telescopic rod 21. The ultraviolet lamp 23 is detachably fixed to the integrated telescopic rod 21 through the C-shaped buckle 22, which facilitates the quick installation and removal of the ultraviolet lamp 23, while ensuring the stability of the ultraviolet lamp 23 during the test and effectively preventing the ultraviolet lamp 23 from loosening or falling off. The C-shaped buckle 22 is made of elastic material and fits onto the rod body of the integrated telescopic rod 21. The ultraviolet lamp 23 is fixed in the opening of the C-shaped buckle 22 and corresponds one-to-one with the C-shaped buckle 22. The outer frame of the test observation box 4 is provided with a wire hole 12. After the wire is threaded, the wire hole 12 is surrounded by a dense mesh. The UV lamp 23 is sealed with a sealing ring or sealant. The connecting wire of the UV lamp 23 exits from the top of the integrated telescopic rod 21. The connecting wires of the UV lamp 23, fan, temperature control module, sensing module and force sensor 20 pass through the wiring hole 12 and are electrically connected to the corresponding control module. The C-shaped buckle 22 can slide along the integrated telescopic rod 21. The C-shaped buckle 22 is provided with corresponding screw holes. Each C-shaped buckle 22 is connected and fixed with bolts (not shown in the figure), realizing dynamic adjustment, flexible installation and precise positioning. The position and number of UV lamps 23 can be quickly adjusted according to the test requirements.

[0042] The power cord of the ultraviolet lamp tube 23 is wrapped with three layers of material from the inside out, including an inner fluororubber insulation layer, a middle tin-plated copper wire braided shielding layer, and an outer polytetrafluoroethylene anti-aging sheath. It is connected through the wire hole 12 on the test observation box 4, which effectively extends the service life and ensures the safety of the test and ensures the smooth progress of the test process.

[0043] The force sensor 20 has a range of 0~200 N, an accuracy of ±0.3%FS, and an output signal of 4~20 mA digital signal. It was purchased from Nanjing Chiyuan System Engineering Co., Ltd., model CYH-3X-B.

[0044] The flexible pressure rope 18 is covered with a silicone sleeve to prevent it from abrading the surface of the greenhouse film 15. In this embodiment, the flexible pressure rope 18 is made of Dyneema material (approximately 2-4 mm wide), but high-strength polyester fiber material can also be used.

[0045] The recessed door 10 features a double-door design, with the door secured in the middle by a sealing strip. This double-door design ensures better sealing of the cabinet. Optionally, multiple observation platforms 13 can be set up inside the test observation box 4. Each observation platform 13 can be independently equipped with a greenhouse film fixing frame 16 and fix the greenhouse film 15 to realize multiple sets of comparative tests. In this embodiment, only one set of observation platforms 13 is set up.

[0046] The bottom surface of the upper environmental chamber 8, the top surface of the lower environmental chamber 9, and the upper and lower ends of the test observation chamber 4 are all equipped with sealing components (such as rubber sealing strips or silicone sealing rings), which together form a sealed overall structure.

[0047] The greenhouse film fixing frame 16 can be made of various materials as needed, as long as it does not affect the test. In this embodiment, the greenhouse film fixing frame 16 is made of aluminum alloy.

[0048] The five inner walls of the upper environmental chamber 8 and the lower environmental chamber 9 are all covered with thermal insulation material (such as polyurethane foam, rock wool, etc.). Waterproof aluminum foil is fixed to the surface of the thermal insulation material (attached with high-temperature resistant adhesive). The environmental chamber has a built-in fan and compressor (the fan can be installed inside the upper environmental chamber 8 or the lower environmental chamber 9 as needed; the compressor is installed inside both the upper environmental chamber 8 and the lower environmental chamber 9). The interface on its wall is connected to the downstream of the humidifier 7. The inside of the interface is sealed with a sealing component (such as a rubber sealing strip or a silicone sealing ring). The compressor can cool or heat. The fan is used to continuously circulate air during the test to ensure that the temperature distribution inside the test observation chamber 4 is uniform and constant, effectively preventing abnormal aging of the greenhouse film 15 material or fire caused by local overheating, thereby improving the safety of the test and the accuracy of temperature control. The humidifier 7 adjusts the humidity inside the environmental chamber to create a continuous set environment, thereby realizing the adjustment and control of the temperature and humidity inside the assembled and sealed upper environmental chamber 8, lower environmental chamber 9 and test observation chamber 4.

[0049] Device Example 2 An aging test device that considers the stress on the greenhouse film has an overall structure that is basically the same as that in embodiment 1, except that at least two sets of observation platforms 13 are set in the test observation box 4 in this embodiment.

[0050] Following the same method as in embodiment 1, a rectangular greenhouse film fixing frame 16 is set on each set of observation platform 13 and support plate 14. Inside the greenhouse film fixing frame 16, there are arc-shaped arch frames 17 and flexible film pressing ropes 18 with symmetrical shapes along both sides of the greenhouse film fixing frame 16. The greenhouse film 15 is supported above the arc-shaped arch frames 17 and fixed below the flexible film pressing ropes 18. One end of the flexible film pressing rope 18 is connected to the rotating tension knob 19 at the end plate of the greenhouse film fixing frame 16, and the other end is connected to the force sensor 20 at the opposite end plate of the greenhouse film fixing frame 16. The tension of the greenhouse film 15 can be precisely adjusted so that the greenhouse film 15 is subjected to force in a natural curved state. The force sensor 20 is connected to the control module.

[0051] Device Example 3 like Figure 10 As shown, an aging test device considering the stress on the greenhouse film has an overall structure that is basically the same as that in embodiment 1. The difference is that in this embodiment, instead of a rotary tension knob 19, a set of electric tension actuators is provided. The connecting wires of the electric tension actuators are electrically connected to the corresponding upper environmental box control panel 5 and / or lower environmental box control panel 6 through the wire hole 12. The electric tension actuator includes a stepper motor 27, a reduction gear set 28, and a winding reel 29. The electric tension actuator is fixed to the end plate of the greenhouse film fixing frame 16. The end of the stepper motor 27 is connected to the reduction gear set 28 and the winding reel 29 in sequence. The reduction gear set 28 amplifies the torque of the stepper motor 27 and applies it to the winding reel 29. The end of the flexible film pressing rope 18 is fixedly wound around the electric tension actuator. On the winding reel 29 of the device, the control module integrates a PID industrial general tension control algorithm. A target tension value is set on the control module, and the tension of the film is monitored in real time by the force sensor 20. The feedback value is compared with the set value. When the tension value is found to be lower than the set value due to film slack, creep, temperature changes, etc., the control module sends a command to the electric tensioning actuator to drive the stepper motor 27 to rotate and tighten the flexible film pressing rope 18, so that the tension tends to the target value. When the tension is greater than the set value, the control module sends a command to the electric tensioning actuator to drive the stepper motor 27 to rotate and release the flexible film pressing rope 18, so that the tension tends to the target value. This realizes fully automatic, high-precision closed-loop control and real-time compensation and correction of tension. During the test, it can also automatically adjust to maintain constant tension.

[0052] The circuit signal transmission of the electric tensioning actuator control system is as follows: Figure 11 As shown, it includes a power module, a force sensor 20, a control module, a judgment module, and a stepper motor 27; The power module is used to supply power to the force sensor 20, the control module (i.e., the upper environmental box control panel 5 and the lower environmental box control panel 6) and the stepper motor 27. The power modules of the force sensor 20 and the stepper motor 27 are integrated inside them, while the control module is powered by an external power supply. After acquiring the monitored tension, the force sensor 20 outputs the monitored tension signal to the control module; The control module takes a set tension value as input and receives a monitored tension signal, and outputs the set tension value and the monitored tension signal to the judgment module. The judgment module is integrated with the control module and shares the same power supply module with the control module. It inputs the set tension value and the monitored tension signal to the control module. When the monitored tension is greater than the set tension, it outputs a tension reduction signal to the stepper motor 27. When the monitored tension is less than the set tension, it outputs a tension increase signal to the stepper motor 27. After the stepper motor 27 receives the tension reduction signal or the tension increase signal, it rotates in the corresponding direction and acts on the downstream reduction gear set 28 and winding wheel 29, thereby tightening or releasing the flexible film pressing rope 18 and changing the stress on the greenhouse film 15. After the stress on the greenhouse film 15 changes, a new monitoring tension signal is obtained by the force sensor 20. The force sensor 20 inputs the new monitoring tension signal back into the control module, and repeats the above process to judge and adjust the tension.

[0053] Method Example 1: An aging test method considering the stress on the greenhouse film, conducted using the aging test apparatus described in Device Example 1, with the following specific steps: (1) First, cut the greenhouse film 15 sample to be tested into the required size for the test, clean the surface with anhydrous ethanol to remove any possible impurities or contaminants, and ensure the accuracy of the test results; After cleaning, the greenhouse film 15 sample was equilibrated for 24 hours in a standard environment (general conditions of 23±2℃ and relative humidity of 45%~55%) to allow the greenhouse film 15 to adapt to the test environment and reduce the influence of environmental factors on the test results. The initial thickness, weight, and optical performance parameters (including surface energy, transmittance, dripping, and light conversion efficiency) of the greenhouse film 15 samples were recorded. Surface energy was tested using the contact angle measurement method according to GB / T 30693-2014 "Measurement of Contact Angle between Plastic Film and Water". Transmittance was tested using the spectrophotometric method according to GB / T 2410-2008 "Determination of Transmittance and Haze of Transparent Plastics". Dripping (anti-fog level) was tested according to GB / T 31726-2015 "Test Method for Anti-fog Properties of Plastic Films". Light conversion efficiency was tested using fluorescence spectroscopy. These parameters will provide a benchmark for subsequent aging tests. After recording, the greenhouse film 15 sample is laid flat on the double-arc arch frame 17 (i.e., the arch frame whose shape is symmetrical along the two sides inside the greenhouse film fixing frame) of the greenhouse film fixing frame 16. The greenhouse film 15 is fixed with a flexible film pressing rope 18. One end of the flexible film pressing rope 18 is fixed to the rotation tension knob 19 on the end plate of the greenhouse film fixing frame 16, and the other end is fixed to the force sensor 20. The target tension was set to 40 N (the sample on the support plate and the observation platform was 40 N). The current value was displayed in real time through the control panel 5 of the upper environmental chamber and the control panel 6 of the lower environmental chamber. The industrial general PID algorithm system automatically prompted the direction of knob rotation to ensure that the force remained constant throughout the test. The flexible film-pressing rope 18 spans the top of the arch frame and is gradually tightened or released by rotating the tension knob 19. Before the test begins, the stress on the greenhouse film during the test can be preset and fixed to simulate the continuous stress state of the greenhouse film 15. The force sensor 20 collects the tension force data in real time and displays the current stress value in real time through the environmental chamber control panel, ensuring that the stress on the greenhouse film 15 is constant and traceable during the test, and improving the consistency between the test conditions and the actual service conditions.

[0054] (2) Place the integrated telescopic rod 21 in the test observation box 4 at the corresponding installation position as determined. First, clean the inner surface of the UV-proof vacuum glass window 11 of the test observation box 4 corresponding to the installation position to ensure that the UV-proof vacuum glass window 11 is dry and free of attachments, so as to provide good contact conditions for the glass suction cup 24. Align one end of the integrated telescopic rod 21 with the glass suction cup 24 at the installation position of the cleaned UV-proof vacuum glass window 11, and press the glass suction cup 24 evenly to make it fit tightly against the glass surface, so as to achieve a firm adsorption between the glass suction cup 24 and the inner surface of the UV-proof vacuum glass window 11. Then, by using the telescopic knob 25, the integrated telescopic rod 21 is stretched axially to the installation position of the UV-proof vacuum glass window 11 on the other side, while maintaining the perpendicularity and parallelism between the integrated telescopic rod 21 and the surface of the UV-proof vacuum glass window 11. The telescopic rod 26 is adjusted to a suitable length and the glass suction cup 24 at the other end is attached and fixed to the installation position of the UV-proof vacuum glass window 11. The integrated telescopic rod 21 is locked in the current state to ensure that the integrated telescopic rod 21 remains stable during the test. Install the corresponding number of C-shaped clips 22 and ultraviolet lamps 23 on the telescopic rod 26 as needed, so that the ultraviolet lamps 23 and C-shaped clips 22 fit tightly to prevent them from loosening or falling off during the test. Ensure that the electrical connection of the ultraviolet lamp tube 23 is reliably connected to the power cord to avoid loose connections or short circuits. After the power cord of the ultraviolet lamp tube 23 is passed through the wire hole 12 on the test observation box 4, it is connected to the power system.

[0055] (3) Connect the water purifier 2 to the water supply system to ensure the purity of the water and avoid scale blockage of the test device due to water quality problems, which would affect the normal conduct of the test and the accuracy of the results; During the connection process, carefully check the sealing of the interface to ensure a firm and reliable connection and prevent water leakage; Close the embedded door 10 of the test observation box 4, and seal the middle part of the embedded door 10 and the junction of the upper environmental box 8, the test observation box 4 and the lower environmental box 9 to ensure that the embedded door 10 and the upper environmental box 8, the test observation box 4 and the lower environmental box 9 are well sealed, so as to maintain the stability of the environment inside the box and ensure the stability and sealing of the overall device. By adjusting the ultraviolet lamps 23, temperature adjustment modules, and humidity adjustment modules connected to them in the upper environmental chamber 8 and lower environmental chamber 9 through the control panel 5 of the upper environmental chamber and the control panel 6 of the lower environmental chamber, the space inside the test observation chamber 4, the upper environmental chamber 8, and the lower environmental chamber 9 can reach a stable test environment. During the adjustment process, closely observe the changes in temperature and humidity inside the environmental chamber to ensure that they reach and stabilize within the set range, providing precise environmental protection for the experiment. Before turning on the ultraviolet lamp 23, check again whether the installation of the ultraviolet lamp 23 is secure and whether the electrical connection is reliable to ensure that the ultraviolet lamp 23 can work normally. The irradiation intensity and time of the ultraviolet lamp 23 should be precisely controlled according to the test requirements to accurately simulate the aging effect of ultraviolet light on the greenhouse film 15 under different environmental conditions.

[0056] (4) During the test, the test environment parameters (temperature, humidity, ultraviolet intensity) and the stress conditions such as the tension of the greenhouse film 15 are monitored and recorded in real time through the upper environmental chamber control panel 5 and the lower environmental chamber control panel 6. For the material performance indicators such as the thickness, weight and optical properties of the greenhouse film 15, the device is stopped every 1000 h, the greenhouse film 15 is taken out and tested and recorded once (the testing method is the same as described above), then the greenhouse film 15 is put back and the device is reassembled to continue operation.

[0057] After the experiment, the collected environmental parameters and performance parameters of the greenhouse film 15 (i.e., thickness, weight, optical properties, tensile force, etc.) were comprehensively analyzed to assess the aging degree of the greenhouse film 15. By comparing the performance parameters before and after the experiment, the aging law of the greenhouse film 15 under the combined effects of high temperature, high humidity, mechanical tensile force, and ultraviolet radiation was understood in detail, providing a scientific basis for the performance evaluation and life prediction of the greenhouse film 15.

[0058] Method Example 2 An aging test method considering the stress on the greenhouse film is carried out using the aging test device described in Device Example 2; The aging test method is basically the same as that described in Method Example 1, except that the test observation box 4 is equipped with multiple observation platforms 13. Each set of observation platforms 13 and support plates 14 is equipped with corresponding arc-shaped arch frames 17 and greenhouse film 15 samples, which are fixed with flexible film pressing ropes 18 to realize the comparative test of more than three sets of greenhouse film 15 samples.

[0059] Different materials can be used for the various groups of greenhouse film 15 samples. They are treated under the same test conditions in the test observation box 4. The position of the ultraviolet lamp is adjusted through pre-experiment to make the radiation to each greenhouse film 15 the same. The greenhouse films 15 of different materials are aged under the same temperature, humidity, tensile force and ultraviolet radiation conditions. The differences in aging performance of greenhouse films 15 of different materials under the combined action of high temperature, high humidity, mechanical tensile force and ultraviolet radiation can be compared and analyzed.

[0060] Method Example 3 An aging test method considering the stress on the greenhouse film is carried out using the aging test device described in Device Example 2; The aging test method is basically the same as that described in Method Example 2, except that two observation platforms 13 are set up. The greenhouse film 15 laid on the observation platform 13 and the support plate 14 is made of the same material. By subjecting the same greenhouse film 15 to different stress conditions, the aging performance differences of the same greenhouse film 15 under different stresses and the combined effects of high temperature, high humidity and ultraviolet radiation can be compared and analyzed. For example, the tension of the upper observation platform 13 is set to 40 N, the tension of the lower observation platform 13 is set to 80 N, and the support plate is not tensioned, so the stress remains constant throughout the test.

[0061] Method Example 4 An aging test method considering the stress on the greenhouse film is carried out using the aging test device described in Device Example 3. The method is basically the same as that in Method Example 1, except for step (1), which is as follows: After recording the initial thickness, weight, and optical performance parameters of the greenhouse film sample 15, the sample was laid flat on the double-sided arc-shaped arches 17 of the greenhouse film fixing frame 16. The greenhouse film 15 was then secured with a flexible pressure rope 18, one end of which was fixed to the winding wheel 29 of the electric tensioning actuator, and the other end to the force sensor 20. The target tension value was set via the control panel, and the system immediately activated its automatic monitoring and compensation mode. The control module automatically controlled the electric tensioning actuator based on real-time feedback data from the force sensor 20, precisely adjusting and stabilizing the greenhouse film tension at the set value. During the experiment, this closed-loop system continuously operated, automatically compensating for tension attenuation caused by material creep, temperature fluctuations, and other factors, ensuring dynamic stability of the force throughout the experiment.

[0062] The experiment conducted using Method Example 4 can automatically and in real time adjust the stress on the film inside the chamber after the device is sealed and the test begins. Compared with Method Examples 1-3, which can only adjust and fix the force before the aging test device is sealed, Method Example 4 achieves stable and controllable stress on the film during the test.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any equivalent substitutions or modifications made by those skilled in the art within the spirit and principle of the present invention without any creative effort should be included within the protection scope of the present invention.

Claims

1. An aging test device considering the stress on greenhouse film, comprising a main frame and an upper environmental chamber, a test observation chamber, and a lower environmental chamber mounted on the main frame, wherein the bottom of the upper environmental chamber is open, the top of the lower environmental chamber is open, and the top and bottom of the test observation chamber are both open; the upper environmental chamber, the test observation chamber, and the lower environmental chamber cooperate with each other and are sealably connected; the device includes a control module, and further includes a sensing module, a temperature regulation module, and an ultraviolet regulation module inside the environmental chamber, as well as a humidity regulation module communicating with the interior of the environmental chamber; the test observation chamber has an embedded door on the front side, and the other three sides are ultraviolet-proof vacuum glass windows; characterized in that: A horizontal observation platform is detachably fixed inside the test observation box, and a support plate with through holes is fixed at the bottom. A rectangular film fixing frame is set on the observation platform and the support plate. Inside the film fixing frame, there are arc-shaped arches symmetrically arranged along both sides of the film fixing frame. The film is supported above the arc-shaped arches and fixed below the flexible film pressing rope. The top of the arc-shaped arches is equipped with a flexible film pressing rope. One end of the flexible film pressing rope is connected to a rotating tensioning device at the end plate of the film fixing frame, and the other end is connected to a force sensor fixedly connected to the film fixing frame at the other end plate of the rotating tensioning device. The end of the flexible film pressing rope is connected to the force receiving end of the force sensor through a clamp. The force sensor is connected to and wiredly connected to the control module.

2. The aging test apparatus according to claim 1, characterized in that, The control module consists of an upper environmental chamber control panel, a lower environmental chamber control panel, and a central processing unit integrated into the upper and lower environmental chamber control panels, all mounted on the main frame. The sensing module includes a temperature sensor, a humidity sensor, and an ultraviolet sensor fixedly installed inside the environmental chamber. A fan, a temperature regulation module, an ultraviolet regulation module, a force sensor, and a sensing module installed inside the environmental chamber, as well as a humidity regulation module connected to the interior of the environmental chamber, are electrically connected to the upper and lower environmental chamber control panels.

3. The aging test apparatus according to claim 2, characterized in that, The rotary tensioning device is a rotary tensioning knob, which is threaded to the end plate of one end of the film fixing frame. When rotated, it can retract the end of the flexible film pressing rope wrapped on it. The upper environmental box control panel and the lower environmental box control panel have built-in PID industrial general tension control algorithm. The target tension value is set, and the system automatically prompts "increase / decrease" the rotary tension force by comparing the sensor feedback value with the set value in real time.

4. The aging test apparatus according to claim 2, characterized in that, The rotary tensioning device is an electric tensioning actuator, which includes a stepper motor, a reduction gear set, and a winding reel. The electric tensioning actuator is fixed to the end plate of the greenhouse film fixing frame. The end of the stepper motor is connected to the reduction gear set and the winding reel in sequence. The end of the flexible film pressing rope is fixedly wound on the winding reel of the electric tensioning actuator. The control module integrates a PID industrial general tension control algorithm.

5. The aging test apparatus according to claim 4, characterized in that, The electric tensioning actuator control system includes a power module, a force sensor, a control module, a judgment module, and a stepper motor. The power module supplies power to the force sensor, control module, and stepper motor; After the force sensor acquires the monitored tension, it outputs the monitored tension signal to the control module; The control module takes a set tension value as input and receives a monitored tension signal, and outputs the set tension value and the monitored tension signal to the judgment module. The judgment module is integrated with the control module. The control module receives the set tension value and the monitored tension signal. When the monitored tension is greater than the set tension, the control module outputs a tension reduction signal to the stepper motor. When the monitored tension is less than the set tension, the control module outputs a tension increase signal to the stepper motor. After the stepper motor receives the tension reduction signal or the tension increase signal, it rotates in the corresponding direction and acts on the downstream reduction gear set and winding wheel, thereby tightening or releasing the flexible film pressing rope and changing the stress on the greenhouse film. After the stress on the greenhouse film changes, a new monitoring tension signal is obtained by the force sensor. The force sensor then inputs the new monitoring tension signal back into the control module, and the above process is repeated cyclically to judge and adjust the tension.

6. The aging test apparatus according to any one of claims 1-5, characterized in that, A fan, a temperature control module, an ultraviolet control module, and a sensor module are installed inside the upper and lower environmental boxes. The humidity control module is connected to the upper and lower environmental boxes. The force sensor is correspondingly set with the greenhouse film fixing frame. Each of the fan, temperature control module, humidity control module, ultraviolet control module, sensor module, and force sensor is electrically connected to one of the control panels of the upper and lower environmental boxes according to its relative position. The humidity control module includes a water tank installed on the main frame, a humidifier installed on the main frame, and a water purifier. The downstream of the water tank is connected to the humidifier. The upper and lower environmental boxes have adapter interfaces on their walls for connecting to the pipes connected to the humidifier outlet. The water outlet of the water purifier is connected to the water tank. The water purifier purifies the water from the water supply system and then sends it into the water tank. The humidifier takes water from the water tank. The water is atomized in the humidifier and then sent through pipes into the assembled upper environmental box, lower environmental box, and test observation box. The water mist circulates under the action of the fan inside the box to regulate the humidity. The humidity sensor can monitor the humidity data in real time. The temperature control module is a compressor installed in the upper and lower environmental boxes; The ultraviolet adjustment module includes an ultraviolet lamp and an integrated telescopic rod. The integrated telescopic rod is detachably fixed to the inside of the two opposite ultraviolet-proof vacuum glass windows of the test observation box. The integrated telescopic rod consists of glass suction cups at both ends, telescopic knobs inside the glass suction cups, and a telescopic rod in the middle. It is physically adsorbed onto the surface of the ultraviolet-proof vacuum glass window through the glass suction cups. The integrated telescopic rod has an inner and outer sleeve structure, and its axial length can be adjusted from 30 to 50 cm using a telescopic knob. A C-shaped buckle is located at the bottom of the integrated telescopic rod, through which the ultraviolet lamp is detachably fixed. The C-shaped buckle is made of elastic material and fits onto the rod body. The ultraviolet lamp is fixed within the opening of the C-shaped buckle. The outer frame of the test observation box has a wire hole, which is sealed with a sealing ring or sealant after the wire is threaded through. The connection wire of the ultraviolet lamp exits at the top of the integrated telescopic rod. The connection wires of the ultraviolet lamp, fan, temperature control module, sensing module, and force sensor exit through the wire hole and are electrically connected to the corresponding control module. The C-shaped buckle can slide along the integrated telescopic rod, and corresponding screw holes are provided on the C-shaped buckle. The C-shaped buckles are connected and fixed with bolts.

7. The aging test apparatus according to any one of claims 1-5, characterized in that, The power cord of the ultraviolet lamp tube is wrapped with three layers of material from the inside out, including an inner fluororubber insulation layer, a middle tin-plated copper wire braided shielding layer, and an outer polytetrafluoroethylene anti-aging sheath, and is connected through the wire hole on the test observation box. The observation platform is fixed to the grid plate inside the test observation box; The flexible pressure membrane rope is covered with a silicone sleeve. The recessed cabinet door features a double-door design, with the door secured in the middle by a sealing strip; The bottom surface of the upper environmental chamber, the top surface of the lower environmental chamber, and the upper and lower ends of the test observation chamber are all equipped with sealing components, which together form a sealed overall structure.

8. The aging test apparatus according to any one of claims 1-5, characterized in that, The upper and lower environmental boxes have insulation material pasted on all five inner walls, and waterproof aluminum foil is fixedly installed on the surface of the insulation material. The environmental box has a built-in fan and compressor, and an interface is opened on its wall to connect to the downstream of the humidifier. The interface is sealed with a sealant.

9. An aging test method considering the stress on the greenhouse film, performed using the aging test apparatus described in claims 1-8, characterized in that, The specific steps include: (1) Cut the greenhouse film sample to be tested into the required size for the test, clean the surface to remove impurities and contaminants, then balance it under standard conditions and record the initial parameters of the greenhouse film sample; lay the greenhouse film sample flat on the double-sided arc arch frame of the greenhouse film fixing frame, fix the greenhouse film with flexible film pressing rope, one end of the flexible film pressing rope is fixed through the rotation tensioning device of the end plate of the greenhouse film fixing frame, and the other end is fixed to the force sensor. After setting the target tension force, adjust the rotation tensioning device according to the current value displayed on the control panel until the tension force is adjusted to the set value; (2) Place the integrated telescopic rod in the corresponding installation position inside the test observation box. First, attach the glass suction cup at one end of the integrated telescopic rod to the corresponding position. Then, extend the integrated telescopic rod by using the telescopic knob and attach the glass suction cup at the other end to the corresponding UV-proof vacuum glass window. The length of the integrated telescopic rod corresponds to the inside of the test observation box and the glass suction cup is fixed. Lock the integrated telescopic rod to ensure its stability during the test. Install the corresponding number of C-shaped buckles and ultraviolet lamps on the telescopic rod so that the ultraviolet lamps and C-shaped buckles fit tightly together. Connect the power cord of the ultraviolet lamp to the power system after passing it through the wire hole. (3) Connect the water purifier to the water supply system; then close the embedded door of the test observation box, and seal the middle of the embedded door and the junction of the upper environmental box, the test observation box and the lower environmental box; turn on the control module, and turn on one or more of the corresponding temperature adjustment module, humidity adjustment module and ultraviolet adjustment module until the space inside the test observation box, the upper environmental box and the lower environmental box reaches a stable test environment; (4) Monitor and record the performance indicators of the greenhouse film through the control panel of the upper environmental box and the control panel of the lower environmental box. After the test, analyze the collected parameters and evaluate the aging degree of the greenhouse film.

10. The aging test method according to claim 9, characterized in that, In step (1), the surface of the greenhouse film sample is cleaned with anhydrous ethanol to remove any possible impurities and contaminants; the sample is equilibrated under standard conditions for at least 24 hours; the initial thickness, weight, and optical performance parameters of the greenhouse film sample are recorded; the greenhouse film fixing frame is a rectangular structure with an arc-shaped arch frame symmetrically arranged on both sides inside. The pressure rope spans the top of the arch frame and is gradually tensioned or released by a rotating tensioning device. The force sensor collects tension data in real time and displays the current force value in real time through the control panel of the environmental chamber. Before placing the integrated telescopic rod, clean the inner surface of the UV-proof vacuum glass window of the test observation box to ensure that the surface is dry and free of any adhering substances; the integrated telescopic rod extends along the length of the test observation box and is perpendicular to the UV-proof vacuum glass window it adsorbs; after installing the UV lamp tube, ensure that the electrical connection of the UV lamp tube is reliably connected to the power cord. The initial parameters in step (1) are the thickness, weight, and optical performance parameters of the greenhouse film; the parameters monitored in real time in step (4) include the test environment parameters and the tensile force on the greenhouse film. The environmental parameters include temperature, humidity, and ultraviolet intensity. The test collection parameters include the environmental parameters as well as the tensile force, thickness, weight, and optical performance parameters of the greenhouse film. The optical performance parameters include surface energy, transmittance, dripping, and light conversion efficiency. The tensile force, temperature, humidity, and ultraviolet intensity of the greenhouse film in the test collection parameters are monitored in real time through the control panel of the upper environmental box and the control panel of the lower environmental box. The thickness, weight, and optical performance parameters are stopped every 1000 h, the greenhouse film is removed, and the data is tested and recorded once. Then the greenhouse film is put back, the assembly device is reassembled, and the operation continues.

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