Granary storage monitoring system based on optical fiber sensing

Abstract

The invention relates to the technical field of grain storage, and discloses a granary storage monitoring system based on optical fiber sensing, which comprises a form monitoring module and a leakage monitoring module, the form monitoring module comprises a plurality of form monitoring units, and the form monitoring units are vertically arranged on the inner wall of a granary in an array mode. The form monitoring unit comprises a plurality of sensing optical fiber channels, each sensing optical fiber channel is subjected to stress analysis, and comparison is carried out through the data comparison unit. According to the invention, the sensing optical fiber technology is creatively utilized to carry out uninterrupted real-time monitoring on the granary, and various potential safety hazards possibly caused by deformation of the granary are quickly captured, so that accidents are effectively prevented, and a firmer safety defense line is built for grain storage.

Description

Technical Field

[0001] The invention relates to the technical field of grain storage, and in particular to a grain storage monitoring system based on optical fiber sensing. Background Art

[0002] A granary is a warehouse for storing grain, designed to protect the harvested grain from natural disasters, pests and corruption, and to provide a controlled environment to maintain the quality and integrity of the grain. Temperature and humidity are important factors affecting grain quality. Under excessively high or low humidity and temperature, grain may be affected by mildew, germination, and insect pests. Structurally, a granary usually includes a warehouse, warehouse doors, warehouse windows, manholes, grain retaining plates (doors) and other parts. The warehouse is the main part for storing grain and must withstand loads such as wind loads, snow loads, earthquakes, and the pressure of grain. The setting of warehouse doors and windows must take into account the convenience of grain entry and exit processes and daily management. The manholes facilitate the custodians to enter and exit the granary for inspection or maintenance.

[0003] When currently granaries are in use, the corresponding sensors are generally inserted directly into the grain to monitor the grain temperature. The stress of the inner wall of the granary cannot be monitored, and the granary may be deformed and damaged. In addition, when the granary is damaged and leaking, it cannot be discovered in time.

[0004] In view of this, the present application proposes a granary storage monitoring system based on optical fiber sensing in view of the fact that existing granaries do not have the function of deformation monitoring. Summary of the invention

[0005] The main purpose of the present invention is to provide a granary storage monitoring system based on optical fiber sensing, which can effectively solve the problem that when the current granary is in use, the corresponding sensor is generally directly inserted into the grain to monitor the temperature of the grain, and the stress of the inner wall of the granary cannot be monitored, the granary may be deformed and damaged, and the damage and leakage of the granary cannot be discovered in time.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A grain storage monitoring system based on optical fiber sensing, including a morphology monitoring module and a leakage monitoring module:

[0008] The morphology monitoring module includes a plurality of morphology monitoring units, each of which includes a deformation monitoring device, and the deformation monitoring device is installed on the inner wall of the granary;

[0009] The morphology monitoring unit includes several sensing optical fiber channels. Stress analysis is performed in each sensing optical fiber communication channel, and the stress is compared by the data comparison unit. The stress of each point at each time is monitored according to the morphology monitoring units arranged in the granary, and the stress change data of the abnormal point and its surroundings are recorded. The obtained data is expanded to form the data to be processed. The original code of the data record is: v_B(T,ε,m i ,X);

[0010] The m in this code i is the morphology monitoring unit number, X is the distance from the optical fiber signal transmitting end to the recording point. When the data at a certain point changes, the data comparison unit compares the current data of the point with the average of previous data and the average of nearby data.

[0011] Preferably, each of the sensing optical fiber communication channels is close to the inner wall of the granary. Assuming that the pressure on the grain side is evenly distributed, we can use the following formula to calculate the hoop stress on the granary wall. The hoop stress measured on the sensing optical fiber of each communication channel can be expressed as:

[0012]

[0013] Where ε is the hoop stress on the silo wall; r is the radius of the silo; t is the material thickness of the inner silo wall; L is the lateral pressure of the grain on the silo wall;

[0014] Generally, under the condition of static equilibrium, for a circular silo, we can imagine cutting a narrow beam of unit width from the silo wall along the axial direction and perform a force analysis on it. Then the lateral pressure of grain on the silo wall can be expressed as:

[0015]

[0016] Where L is the lateral pressure per unit area; w is the grain bulk density (weight / unit volume); u' is the friction coefficient between the grain and the silo wall; R is the silo bottom area divided by the circumference (unit length); k is the ratio of the lateral pressure on the grain pile to the vertical pressure (a constant per unit length of the grain depth under consideration); and h is the grain depth (unit length).

[0017] Preferably, the shape, size and type of grain stored in the silo will change the friction and circumferential force between the grain and the silo wall. On the basis of the above formula (2), the uniform distribution constant di of different types of grain is added and substituted into formula (2), and the result is:

[0018]

[0019] The BOTDA system using the sensing fiber can generally effectively express the relationship between the sensing fiber and the strain, and the formula is:

[0020] Δvb=ΔεC ε (4)

[0021] Where Δvb represents the change in Brillouin frequency shift; C ε It is a constant related to the optical fiber material, its manufacturing process, doping concentration and other factors. It describes the proportional relationship between the change in Brillouin frequency shift and strain. Δε represents the change in strain on the optical fiber.

[0022] Combining equation (3) and equation (4) and adding the relationship between the sensing fiber and temperature, we can finally get:

[0023]

[0024] Where v_B(T,ε) is the Brillouin frequency shift when the temperature is T and the strain is ε; v_B0 is the Brillouin frequency shift at the reference temperature T0 and without strain; C_T is the temperature coefficient of the Brillouin frequency shift, which indicates the change in the Brillouin frequency shift when the temperature changes by 1°C; C_ε is the strain coefficient of the Brillouin frequency shift, which indicates the change in the Brillouin frequency shift when the strain changes by 1με (microstrain), and T0 is the reference temperature.

[0025] Preferably, the leakage monitoring module includes multiple leakage monitoring units, and the leakage monitoring unit includes a leakage monitoring device. An array of multiple leakage monitoring devices is arranged on the inner wall of the granary. Each leakage monitoring unit includes a transmitting end and a receiving end. In an initial state, the transmitting end and the receiving end are not fully connected.

[0026] Preferably, the deformation monitoring device is a single-channel optical fiber configuration, and the deformation monitoring device includes a second transmitter and a second receiver, an optical fiber is provided between the second transmitter and the second receiver, the second transmitter and the second receiver form a communication channel through the optical fiber, the optical fiber is arranged close to the inner wall of the granary, a protective tube is provided on the outside of the optical fiber, and the optical fiber of the morphology monitoring device is arranged in a spiral shape, so that the communication channel between the second transmitter and the second receiver is spiral.

[0027] Preferably, when the optical fibers are arranged in a spiral shape, n i The number is always 1, and the code of the point where the Brillouin frequency shift occurs and the four points close to it should be: v_B(T, ε, m i , X), v_B(T, ε, m i+1 , X+), v_B(T, ε, m i+2 ,X-)、v_B(T,ε,m i+2 , X+S), v_B(T, ε, m i+2, XS), can also be increased or reduced according to the pitch, where D is the cylinder diameter, that is, the projection diameter, and s is the pitch.

[0028] Preferably, the deformation monitoring device is a multi-channel optical fiber configuration, and the deformation monitoring device includes the morphology monitoring device and also includes a second fixed seat, the second fixed seat is vertically installed on the inner wall of the granary, and a plurality of fourth transmitters and fourth receivers are installed on the second fixed seat. The fourth transmitters and fourth receivers are arranged in a one-to-one correspondence, and each fourth transmitter forms a communication channel with the corresponding fourth receiver through optical fiber. The fourth receiver is in a circular shape, and the multiple communication channels are independent of each other.

[0029] Preferably, when the optical fibers are arranged in a vertical array, n i The number is always 1, and the code of the point where the Brillouin frequency shift occurs and the nine points close to it should be: v_B(T, ε, m i , X), v_B(T, ε, m i , X1), v_B(T, ε, m i , X2), v_B(T, ε, m i-1 , X), v_B(T, ε, m i-1 , X1), v_B(T, ε, m i-1 , X2), v_B(T, ε, m i+1 , X), v_B(T, ε, m i+1 , X1), v_B(T, ε, m i+1 , X2).

[0030] Preferably, the leakage monitoring device includes a plurality of wall grooves, which are installed on the inner wall of the granary, and the cross-section of the wall groove is in the shape of the letter "U". A first transmitter and a first receiver are cooperatively installed in the wall groove, and the first transmitter and the first receiver are cooperatively connected. A protective cover is provided on the wall groove, and a plurality of through holes are opened on the protective cover.

[0031] Preferably, a glass tube is provided in the wall groove, two ends of the glass tube are respectively arranged to correspond to the first transmitter and the first receiver, a plastic sleeve is provided on the outside of the glass tube, and a cavity is opened between the plastic sleeve and the glass tube.

[0032] The present invention innovatively uses the sensing fiber technology to implement uninterrupted real-time monitoring of the granary, aiming to quickly capture various safety hazards that may be caused by deformation of the granary, so as to effectively prevent accidents and build a more solid safety line for grain storage. In practical applications, the sensing fiber is cleverly arranged inside the granary. Its highly sensitive characteristics enable even the slight deformation caused by the change of force or slight external force inside the granary to be accurately sensed and recorded. The system can not only record these stress changes in real time, but also conduct in-depth analysis of these data through advanced comparison and analysis algorithms, and then accurately judge the health status of the granary structure, and automatically trigger corresponding alarm information when necessary, so that managers can quickly take countermeasures. More advanced is that when the granary suffers major damage, resulting in the breakage of the optical fiber inside the sensing fiber, the system will immediately identify this extreme situation and generate a specific emergency signal to notify the staff as soon as possible to ensure that they can intervene immediately and effectively curb the further deterioration of the situation; it greatly enhances the safety of the grain storage environment and sets a new benchmark for safety management in the grain storage industry.

[0033] The present invention not only has the function of efficiently monitoring the humidity and leakage inside the granary, but also can respond intelligently when the humidity in the granary exceeds the standard. Specifically, when the humidity inside the granary rises abnormally, the frosted glass surface on the outside of the glass tube in the leakage monitoring device will show a higher light reflection characteristic, resulting in a significant enhancement of the light signal captured by the fourth receiver. Subsequently, the leakage monitoring module will immediately trigger an alarm message of excessive humidity so that timely countermeasures can be taken. Furthermore, if the monitored light reflectivity climbs above the preset threshold, the system will determine that the granary may be damaged and leaking, and will issue an emergency alarm through the leakage monitoring module to ensure that the problem can be quickly noticed and handled.

[0034] The parts not involved in the device are the same as those in the prior art or can be implemented by using the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The present invention is a simplified system block diagram of a grain storage monitoring system based on optical fiber sensing.

[0036] Figure 2 It is a flow chart of the present invention.

[0037] Figure 3 This is a schematic diagram of the structure of the granary currently in use.

[0038] Figure 4 This is a schematic diagram of the internal structure of the granary.

[0039] Figure 5 It is a schematic diagram of the basic structure of the single-channel morphology monitoring device of the present invention.

[0040] Figure 6 It is a schematic diagram of the basic structure of the multi-channel morphology monitoring device of the present invention.

[0041] Figure 7 It is a schematic diagram of the installation positions of the fourth transmitter and the fourth receiver of the present invention.

[0042] Figure 8 This is a point record relationship diagram of the single-channel morphology monitoring device of the present invention.

[0043] Fig. 9 It is a point record relationship diagram of the present invention.

[0044] Fig.10 It is a schematic diagram of the installation position of the wall groove of the leakage monitoring device of the present invention.

[0045] Fig.11 It is a schematic diagram of the basic structure of the present invention.

[0046] Fig.12 For the present invention Fig.11 Top view of the .

[0047] Fig.13 For the present invention Fig.12 AA section view.

[0048] Fig.14 It is a line graph of humidity and light reflectivity between the first transmitting end and the first receiving end of the present invention.

[0049] In the figure: 101, wall groove; 103, first transmitter; 104, first receiver; 105, protective cover; 106, through hole; 107, glass tube; 108, plastic sleeve; 109, cavity; 201, second transmitter; 202, second receiver; 203, optical fiber; 207, second fixing seat; 208, fourth transmitter; 209, fourth receiver. DETAILED DESCRIPTION

[0050] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0051] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0052] Reference Figure 1-3 An embodiment of the present disclosure provides a grain silo storage monitoring system based on optical fiber sensing, including a morphology monitoring module and a liquid leakage monitoring module.

[0053] The morphology monitoring module includes several morphology monitoring units, which are vertically arrayed on the inner wall of the granary. The morphology monitoring unit includes several sensing optical fiber channels. Stress analysis is performed on each sensing optical fiber communication channel respectively, and comparison is performed through a data comparison unit.

[0054] Each sensing optical fiber communication channel is close to the inner wall of the granary. Assuming that the pressure on the grain side is evenly distributed, we can use the following formula to calculate the hoop stress on the granary wall. The hoop stress measured on the sensing optical fiber of each communication channel can be expressed as:

[0055]

[0056] Where, is the hoop stress on the silo wall; r is the radius of the silo; t is the material thickness of the inner silo wall; L is the lateral pressure of grain on the silo wall;

[0057] Generally, under the condition of static equilibrium, for a circular silo, we can imagine cutting a narrow beam of unit width from the silo wall along the axial direction and perform a force analysis on it. Then the lateral pressure of grain on the silo wall can be expressed as:

[0058]

[0059] Where L is the lateral pressure per unit area; w is the bulk density of grain (weight / unit volume); u is the friction coefficient between grain and the silo wall; R is the silo bottom area divided by the perimeter (unit length); k is the ratio of the lateral pressure on the grain pile to the vertical pressure (a constant under the unit length of the grain depth under consideration); h is the grain depth (unit length);

[0060] However, the shape, size and type of grain stored in the silo will change the friction and circumferential force between the grain and the silo wall. On the basis of the above formula (2), add the uniform distribution constant di of different types of grain and substitute it into formula (2), and we can get:

[0061]

[0062] The BOTDA system using the sensing fiber can generally effectively express the relationship between the sensing fiber and the strain, and the formula is:

[0063] Δvb=ΔεC ε (4)

[0064] Where Δvb represents the change in Brillouin frequency shift; Cε is a constant related to factors such as the optical fiber material, its manufacturing process, and doping concentration, which describes the proportional relationship between the change in Brillouin frequency shift and strain; Δε represents the change in strain on the optical fiber;

[0065] Combining equation (3) and equation (4) and adding the relationship between the sensing fiber and temperature, we can finally get:

[0066]

[0067] Where v_B(T, ε) is the Brillouin frequency shift when the temperature is T and the strain is ε; v_B0 is the Brillouin frequency shift at the reference temperature T0 and without strain; C_T is the temperature coefficient of the Brillouin frequency shift, which indicates the change in the Brillouin frequency shift when the temperature changes by 1°C; C_ε is the strain coefficient of the Brillouin frequency shift, which indicates the change in the Brillouin frequency shift when the strain changes by 1με (microstrain), and T0 is the reference temperature.

[0068] The stress at each point at each time is monitored according to the morphological monitoring units arranged in the granary, and the stress changes at the point and at the time are recorded and arranged in cylindrical data, and the obtained cylindrical data are unfolded to form visual data. The original code of the data record is: v_B(T, ε, mi, X);

[0069] In this code, mi is the morphology monitoring unit number, and X is the distance from the optical fiber signal transmitting end to the recording point.

[0070] When the data at a certain point changes, the data comparison unit compares the current data of the point with the average of previous data and the average of nearby data, and generates a corresponding report based on the corresponding comparison results.

[0071] Reference Figure 1In the detailed operation process shown, we first use a precise processor to accurately control the corresponding transmitter so that it can accurately inject the laser beam into the sensing optical fiber 203. Once the incident light successfully enters the sensing optical fiber 203, the morphology monitoring module will immediately start and begin to collect various data in a comprehensive and detailed manner. During this process, the module is highly sensitive and can quickly detect the existence of any abnormal data points. Once these abnormal points are found, the module will immediately use a pre-set scientific formula to process them and accurately record the calculated stress change value in an external storage device.

[0072] Subsequently, these data will be sent to the data comparison module for strict verification and comparison. This step is crucial because it involves an in-depth comparison of the stress change value of the current abnormal point with the average stress change value of the previous abnormal point. If the data verification fails, it means that the stress change of the current abnormal point is significantly different from the normal pattern, which often indicates that the shape of the granary where the abnormal point is located may have undergone a significant deformation. At this time, the system will immediately trigger a granary deformation warning and use the previously mentioned formula to accurately calculate the abnormal position to ensure that the relevant information can be reported to the corresponding staff as soon as possible so that they can take countermeasures quickly.

[0073] It is worth mentioning that while the morphology monitoring module is running at full capacity, the leakage monitoring module is also working in parallel. The interval scanning time between the two is precisely set to one unit time, ensuring comprehensive and real-time monitoring of the granary status. The leakage monitoring module is composed of multiple carefully designed leakage monitoring units, which are cleverly arranged on the inner wall of the granary in an array. Each unit is equipped with a transmitter and a receiver. In the initial state, these transmitters and receivers are not fully connected, leaving sufficient flexibility for subsequent monitoring work.

[0074] Reference Figure 3 and Figure 4 At present, sensors are generally installed on the pillars inside the granary. Corresponding temperature and humidity sensors are installed on the pillars. This method cannot monitor the condition of the inner wall of the granary, but can only monitor the temperature and humidity of the grain in the granary. However, the inner wall of the granary is directly in contact with the outside world, and its temperature is relatively low, which will cause a large amount of moisture to condense into small droplets on its inner wall, causing the humidity and temperature on one side of the inner wall of the granary to be different from those inside the granary.

[0075] When the leakage monitoring module starts running, although the transmitter and the receiver remain disconnected, the humidity changes between them can be accurately captured. Once the laser intensity received by the receiver increases abnormally and exceeds the preset threshold range, it often means that the humidity between the transmitter and the receiver is too high. This increase in humidity will cause the light reflectivity of the material to increase significantly, thus providing us with an important basis for judging that the humidity in the granary is too high.

[0076] To understand this relationship more intuitively, we can refer to Fig.14 This figure clearly shows the close relationship between humidity and light reflectivity between the transmitter and the receiver. As the humidity continues to increase, the light reflectivity also shows a clear upward trend. This linear correlation provides us with strong evidence and further confirms the impact of humidity changes on light reflectivity.

[0077] Back again Figure 1 In the operation process, when the processor controls the transmitter to inject the laser into the sensing optical fiber 203, the leakage monitoring module also starts to collect data. If the intensity of the optical signal received by a leakage monitoring unit suddenly increases, it indicates that the humidity in the granary may have seriously exceeded the standard. At this time, the system will immediately activate the early warning mechanism and issue an emergency warning of water seepage in the granary to ensure that relevant personnel can quickly take necessary preventive measures to prevent the situation from further deteriorating.

[0078] The single-channel morphology monitoring device includes a second transmitter 201 and a second receiver 202. A sensing optical fiber 203 is provided between the second transmitter 201 and the second receiver 202. The second transmitter 201 and the second receiver 202 form a communication channel through the sensing optical fiber 203. The sensing optical fiber 203 is arranged close to the inner wall of the granary. A protective tube is provided on the outside of the sensing optical fiber 203. The sensing optical fiber 203 of the morphology monitoring device is arranged in a spiral shape, so that the communication channel between the second transmitter 201 and the second receiver 202 is spiral.

[0079] When the sensing optical fiber 203 is arranged in a spiral shape, the number ni is constantly 1, and the coding of the point where the Brillouin frequency shift occurs and the four points close to it should be: v_B(T, ε, mi, X), v_B(T, ε, mi+1, X+), v_B(T, ε, mi+2, X-), v_B(T, ε, mi+2, X+S), v_B(T, ε, mi+2, XS), and can also be increased or reduced according to the pitch. In the above formula, D is the diameter of the cylinder, that is, the projection diameter, and s is the pitch.

[0080] Reference Figure 5 and Figure 8The detailed display shows that the sensing optical fiber 203 is cleverly arranged in a precise spiral arrangement. This layout design is designed to achieve sensitive capture and accurate monitoring of stress changes in the granary structure. When the system detects a specific point where stress changes, it automatically triggers a sophisticated data collection process. This process not only records the information of the stress change point itself, but also reads the data of several points closely surrounding it to ensure the comprehensiveness and accuracy of the analysis.

[0081] Specifically, if Figure 8 As shown in the figure, when the system identifies a stress change point, it will immediately read the data of a total of 25 points radiating from this point. The selection of these 25 points is carefully calculated to fully cover and evaluate the impact of stress changes on the surrounding areas. Assume that at 7:15 Beijing time, the system detects a significant stress change point (which we call a "marked point"), then the system will go back to an earlier time point of 7:00 Beijing time to read and collect stress change data including the marked point and the 24 adjacent points around it. This step is to capture and analyze the baseline state before the stress change in order to compare it with the current state and identify any minor or significant change trends.

[0082] After the data is collected, the system will conduct a key comparative analysis: comparing the stress change value of the marked point with the average stress change data of the 25 points read. This comparison process is crucial because it can help us determine whether the stress change experienced by the marked point is abnormal. If the stress change value of the marked point significantly exceeds the average value of the 25 points by twice or more, the system will immediately generate and trigger a warning signal for grain silo deformation. This warning means that there may be structural safety issues, and immediate measures need to be taken for further inspection and repair to prevent potential grain silo damage or safety accidents.

[0083] On the contrary, if the stress change value of the marked point does not show obvious abnormality compared with the average value of the surrounding points, that is, it remains within a reasonable fluctuation range, then this indicates that the stress condition of the inner wall of the granary is normal and there is no need to worry too much. Through such real-time monitoring and data analysis processes, we can effectively monitor the health of the granary structure and ensure the safety and stability of the grain storage environment.

[0084] The multi-channel morphology monitoring device includes a second fixing seat 207, which is vertically mounted on the inner wall of the granary. A plurality of fourth transmitters 208 and fourth receivers 209 are mounted on the second fixing seat 207. The fourth transmitters 208 and the fourth receivers 209 are arranged one by one. Each fourth transmitter 208 forms a communication channel with the corresponding fourth receiver 209 through the sensing optical fiber 203. The fourth receiver 209 is in a circular shape, and the plurality of communication channels are independent of each other.

[0085] When the sensing optical fiber 203 is arranged in a spiral shape, the number ni is constant at 1, and the codes of the point where the Brillouin frequency shift occurs and the nine points adjacent to it should be: v_B(T, ε, mi, X), v_B(T, ε, mi, X1), v_B(T, ε, mi, X2), v_B(T, ε, mi-1, X), v_B(T, ε, mi-1, X1), v_B(T, ε, mi-1, X2), v_B(T, ε, mi+1, X), v_B(T, ε, mi+1, X1), v_B(T, ε, mi+1, X2)

[0086] Reference Figure 6 , Figure 7 and Fig. 9 The sensor fibers 203 are carefully arranged in a vertical array, which is designed to capture and accurately monitor changes in the stress of the granary structure. When the system detects a specific point where stress changes, it immediately initiates a comprehensive and detailed data collection and analysis process.

[0087] Specifically, if Fig. 9 As shown in the figure, when the system identifies two stress change points, it will quickly read data from a total of 30 points around these two points. The selection of these 30 points is well thought out, aiming to fully cover and deeply analyze the impact of stress changes on the granary structure. Each point carries important stress information, and together they form a detailed data network, providing a solid foundation for subsequent comparative analysis.

[0088] Assume that at 7:15 Beijing time, the system detects two significant stress change points (which we call "marked points"). Next, the system will go back to an earlier time point of 7:00 Beijing time to read and collect stress change data including these two marked points and the 28 adjacent points around them. This step is to capture and analyze the baseline state before the stress change in order to compare it with the current state and identify any minor or significant change trends. It is worth noting that although the data mentioned here is read from 25 points, considering that there are two marked points and their surrounding points, the actual number of points read should be adjusted to 30 to ensure the comprehensiveness and accuracy of the analysis.

[0089] After the data is collected, the system will conduct a critical comparative analysis: the stress change value of each marked point is compared with the average stress change data of the 30 points read. This comparison process is crucial because it can help us determine whether the stress change experienced by the marked point is abnormal. If the stress change value of any marked point significantly exceeds the average of these 30 points by twice or more, the system will immediately generate and trigger a warning signal for grain silo deformation. This warning means that there may be structural safety hazards, and immediate measures need to be taken for further inspection and repair to prevent potential grain silo damage or safety accidents.

[0090] On the contrary, if the stress change values ​​of all the marked points do not show obvious abnormalities compared with the average values ​​of the surrounding points, that is, they remain within a reasonable fluctuation range, then this indicates that the stress condition of the inner wall of the granary is normal and there is no need to worry too much. Through such real-time monitoring and data analysis processes, we can effectively monitor the health of the granary structure and ensure the safety and stability of the grain storage environment. At the same time, this vertical array of sensing optical fibers 203 also provides us with a more intuitive and comprehensive perspective for stress change monitoring, which helps us to more accurately grasp the overall safety status of the granary structure.

[0091] Reference Figure 10-13 The leakage monitoring device includes a plurality of wall grooves 101, which are installed on the inner wall of the granary. The cross-sectional shape of the wall grooves 101 is in the shape of the letter "U". This design not only ensures the stability of the installation, but also provides a good space for the subsequent equipment installation. Inside the wall grooves 101, the first transmitter 103 and the first receiver 104 are precisely matched and installed with reference to Fig.12 They are respectively installed at both ends of the wall groove 101 to establish a stable connection, and the wall groove 101 is in an arc shape.

[0092] The wall groove 101 is also equipped with a protective cover 105, which not only protects the internal equipment from external interference, but also has a number of through holes 106 formed thereon. The design of these through holes 106 allows moisture in the granary to smoothly enter the interior of the wall groove 101, providing the necessary conditions for subsequent monitoring work.

[0093] A glass tube 107 is arranged inside the wall groove 101. The two ends of the glass tube 107 are respectively arranged to correspond to the first transmitter 103 and the first receiver 104 to ensure the transmission path of the laser signal. The outer side of the glass tube 107 is wrapped with a layer of sheath 108. A cavity 109 is formed between the sheath 108 and the glass tube 107. The design of the cavity 109 provides space for the accumulation of moisture.

[0094] It is worth noting that a reflective coating is also applied on the inner side of the plastic sleeve 108, which can effectively enhance the refraction of the laser signal inside the plastic sleeve 108, so that the laser signal can better pass through the glass tube 107 and be reflected on the plastic sleeve 108. At the same time, a number of holes are cleverly opened on the plastic sleeve 108, and these holes are connected to the cavity 109, so that the moisture in the granary can smoothly enter the cavity 109.

[0095] When the humidity in the granary increases, moisture will enter the cavity 109 through the through hole 106 on the protective cover 105 and the holes on the plastic sheath 108. As the humidity continues to increase, the moisture will condense into small water droplets on the glass tube 107. The presence of these small water droplets will increase the transmittance of the glass tube 107, thereby enhancing the refraction effect of the optical fiber 203 in the plastic sheath 108. In this way, when the first transmitter 103 emits a laser, the laser can better pass through the glass tube 107 and reflect on the plastic sheath 108, thereby greatly improving the intensity of the optical signal received by the first receiver 104.

[0096] By monitoring the intensity of the optical signal received by the first receiver 104, we can accurately determine the moisture level in the granary. When the humidity is insufficient, the intensity of the optical signal received by the first receiver 104 will be relatively low; when the humidity is sufficient, the intensity of the optical signal will be significantly improved. This monitoring method based on optical signal intensity is not only accurate and reliable, but also can realize real-time monitoring of the moisture level in the granary.

[0097] In addition, since the wall groove 101 is installed close to the inner wall of the granary, when water mist condenses on the granary wall that is in direct contact with the outside world, small water droplets will form and flow into the wall groove 101 along the inner wall of the granary. In this way, the humidity in the wall groove 101 will increase rapidly, thereby triggering the alarm information more quickly. This design not only improves the monitoring sensitivity, but also provides a strong guarantee for timely handling of moisture problems in the granary.

[0098] The present invention not only has the function of efficiently monitoring the humidity and leakage inside the granary, but also can respond intelligently when the humidity in the granary exceeds the standard. Specifically, when the humidity inside the granary rises abnormally, the frosted glass surface outside the glass tube 107 in the leakage monitoring device will show higher light reflection characteristics, resulting in a significant enhancement of the light signal captured by the fourth receiver. Subsequently, the leakage monitoring module will immediately trigger an alarm message of excessive humidity so that timely countermeasures can be taken. Furthermore, if the monitored light reflectivity rises above the preset threshold, the system will determine that the granary may be damaged and leaking, and send an emergency alarm through the leakage monitoring module to ensure that the problem can be quickly paid attention to and handled.

[0099] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A grain storage monitoring system based on optical fiber sensing, characterized in that: Including morphology monitoring module and leakage monitoring module: The morphology monitoring module includes a plurality of morphology monitoring units, each of which includes a deformation monitoring device, and the deformation monitoring device is installed on the inner wall of the granary; The morphology monitoring unit includes several sensing optical fiber channels. Stress analysis is performed in each sensing optical fiber communication channel, and the stress is compared by the data comparison unit. The stress of each point at each time is monitored according to the morphology monitoring units arranged in the granary, and the stress change data of the abnormal point and its surroundings are recorded. The obtained data is expanded to form the data to be processed. The original code of the data record is: v_B(T,ε,m i ,X); The m in this code i is the morphology monitoring unit number, X is the distance from the optical fiber signal transmitting end to the recording point. When the data at a certain point changes, the data comparison unit compares the current data of the point with the average of previous data and the average of nearby data.

2. According to claim 1, a grain storage monitoring system based on optical fiber sensing is characterized in that: Each of the sensing optical fiber communication channels is close to the inner wall of the granary. Assuming that the pressure on the grain side is evenly distributed, we can use the following formula to calculate the hoop stress on the granary wall. The hoop stress measured on the sensing optical fiber of each communication channel can be expressed as: Where ε is the hoop stress on the silo wall; r is the radius of the silo; t is the material thickness of the inner silo wall; L is the lateral pressure of the grain on the silo wall; Generally, under the condition of static equilibrium, for a circular silo, we can imagine cutting a narrow beam of unit width from the silo wall along the axial direction and perform a force analysis on it. Then the lateral pressure of grain on the silo wall can be expressed as: Where L is the lateral pressure per unit area; w is the grain bulk density (weight / unit volume); u' is the friction coefficient between the grain and the silo wall; R is the silo bottom area divided by the circumference (unit length); k is the ratio of the lateral pressure on the grain pile to the vertical pressure (a constant per unit length of the grain depth under consideration); and h is the grain depth (unit length).

3. According to claim 2, a grain storage monitoring system based on optical fiber sensing is characterized in that: However, the shape, size and type of grain stored in the silo will change the friction and circumferential force between the grain and the silo wall. On the basis of the above formula (2), add the uniform distribution constant di of different types of grain and substitute it into formula (2), and we can get: The BOTDA system using the sensing fiber can generally effectively express the relationship between the sensing fiber and the strain, and the formula is: Δvb=ΔεC ε (4) Where Δvb represents the change in Brillouin frequency shift; C ε It is a constant related to the optical fiber material, its manufacturing process, doping concentration and other factors. It describes the proportional relationship between the change in Brillouin frequency shift and strain. Δε represents the change in strain on the optical fiber. Combining equation (3) and equation (4) and adding the relationship between the sensing fiber and temperature, we can finally get: Where v_B(T,ε) is the Brillouin frequency shift when the temperature is T and the strain is ε; v_B0 is the Brillouin frequency shift at the reference temperature T0 and without strain; C_T is the temperature coefficient of the Brillouin frequency shift, which indicates the change in the Brillouin frequency shift when the temperature changes by 1°C; C_ε is the strain coefficient of the Brillouin frequency shift, which indicates the change in the Brillouin frequency shift when the strain changes by 1με (microstrain), and T0 is the reference temperature.

4. The grain storage monitoring system based on optical fiber sensing according to claim 1 is characterized in that: The leakage monitoring module includes multiple leakage monitoring units, and the leakage monitoring unit includes a leakage monitoring device. The multiple leakage monitoring devices are arranged in an array on the inner wall of the granary. Each leakage monitoring unit includes a transmitting end and a receiving end. In the initial state, the transmitting end and the receiving end are not fully connected.

5. The grain storage monitoring system based on optical fiber sensing according to claim 1 is characterized in that: The deformation monitoring device is a single-channel optical fiber configuration, comprising a second transmitter (201) and a second receiver (202), an optical fiber (203) being arranged between the second transmitter (201) and the second receiver (202), the second transmitter (201) and the second receiver (202) forming a communication channel through the optical fiber (203), the optical fiber (203) being arranged close to the inner wall of the granary, a protective tube being arranged outside the optical fiber (203), the optical fiber (203) of the shape monitoring device being arranged in a spiral shape, so that the communication channel between the second transmitter (201) and the second receiver (202) is in a spiral shape.

6. The grain storage monitoring system based on optical fiber sensing according to claim 5 is characterized in that: When the optical fiber (203) is arranged in a spiral shape, n i The number is always 1, and the code of the point where the Brillouin frequency shift occurs and the four points close to it should be: v_B(T, ε, m i , X), v_B(T, ε, m i+1 , X+), v_B(T, ε, m i+2 ,X-)、v_B(T,ε,m i+2 , X+S), v_B(T, ε, m i+2 , XS), can also be increased or reduced according to the pitch, where D is the cylinder diameter, that is, the projection diameter, and s is the pitch.

7. The grain storage monitoring system based on optical fiber sensing according to claim 1 is characterized in that: The deformation monitoring device is a multi-channel optical fiber configuration. The deformation monitoring device includes the morphology monitoring device and also includes a second fixed seat (207). The second fixed seat (207) is vertically installed on the inner wall of the granary. A plurality of fourth transmitters (208) and fourth receivers (209) are installed on the second fixed seat (207). The fourth transmitters (208) and the fourth receivers (209) are arranged in a one-to-one correspondence. Each fourth transmitter (208) forms a communication channel with the corresponding fourth receiver (209) through the optical fiber (203). The fourth receiver (209) is in a circular shape, and the multiple communication channels are independent of each other.

8. The grain storage monitoring system based on optical fiber sensing according to claim 7 is characterized in that: When the optical fibers (203) are arranged in a vertical array, n i The number is always 1, and the code of the point where the Brillouin frequency shift occurs and the nine points close to it should be: v_B(T, ε, m i , X), v_B(T, ε, m i , X1), v_B(T, ε, m i , X2), v_B(T, ε, m i-1 , X), v_B(T, ε, m i-1 , X1), v_B(T, ε, m i-1 , X2), v_B(T, ε, m i+1 , X), v_B(T, ε, m i+1 , X1), v_B(T, ε, m i+1 , X2).

9. The grain storage monitoring system based on optical fiber sensing according to claim 4 is characterized in that: The liquid leakage monitoring device comprises a plurality of wall grooves (101), wherein the wall grooves (101) are installed on the inner wall of a granary, wherein the cross section of the wall grooves (101) is in the shape of a letter "U", wherein a first transmitter (103) and a first receiver (104) are cooperatively installed in the wall grooves (101), wherein the first transmitter (103) and the first receiver (104) are cooperatively connected, and a protective cover (105) is provided on the wall grooves (101), wherein a plurality of through holes (106) are opened on the protective cover (105).

10. A grain storage monitoring system based on optical fiber sensing according to claim 9, characterized in that: A glass tube (107) is arranged in the wall groove (101), and two ends of the glass tube (107) are respectively arranged to correspond to the first transmitter (103) and the first receiver (104). A sleeve (108) is arranged on the outside of the glass tube (107), and a cavity (109) is provided between the sleeve (108) and the glass tube (107).

Images