CN-121978059-A - Medium phase change state sensing method and system based on prism lens high polymer optical fiber

CN121978059ACN 121978059 ACN121978059 ACN 121978059ACN-121978059-A

Abstract

The invention belongs to the technical field of medium phase change state monitoring, and relates to a medium phase change state sensing method and a medium phase change state sensing system based on prism high polymer optical fibers, wherein the method comprises the steps of inputting incident light signals, enabling the incident angle of the incident light to be larger than a critical angle through a prism end head, the light is totally reflected, a return light signal is received, the return light signal is converted into an electric signal, preprocessing is carried out, and sensing judgment of the medium phase change state of the medium to be detected is carried out based on the preprocessed signal data. The system comprises a main control unit, a light intensity data acquisition instrument and a high polymer optical fiber sensor. The invention utilizes the prism end structure design of the high polymer optical fiber to lead the light to generate total reflection so as to realize the perception of the medium phase change state, does not need to additionally increase a sensor, takes the prism end as a perception part, and the high polymer optical fiber is not only an optical transmission medium but also a perception medium.

Inventors

ZHANG HAIHUA
LIU ZHIBIN
MA XIANFENG
ZHANG HAOJIN
HAN HAN
Chen Qiaoman
LUO YINGJIE

Assignees

同济大学

Dates

Publication Date: 20260505
Application Date: 20260403

Claims (10)

1. The medium phase change state sensing method based on the prism lens high polymer optical fiber is characterized by comprising the following steps of: S1, inputting an incident light signal through a first high polymer optical fiber, and enabling an incident angle of the incident light to be larger than a critical angle through a prism end formed by the end parts of the first high polymer optical fiber and the second high polymer optical fiber So that light is totally reflected; The critical angle The calculation formula of (2) is as follows: ; Wherein, the Is the refractive index of the high polymer optical fiber, The refractive index of the medium to be measured; s2, receiving a return optical signal through a second polymer optical fiber; step S3, acquiring the light intensity of the return light signal measured at the time t in real time by a light intensity data acquisition instrument Converting the return light signal into an electrical signal; s4, preprocessing the converted electric signals, and performing sensing judgment on the medium phase change state of the medium to be tested based on the preprocessed signal data; step S5 when the light intensity of the return light signal When the corresponding electric signal changes and the instantaneous change value tends to infinity, the corresponding electric signal is changed at any time before the change Is the light intensity of the return light signal of (a) Corresponding to the electric signal and any time after the change Is the light intensity of the return light signal of (a) When the ratio of the corresponding electric signals is greater than 1, the medium phase change state of the medium to be measured is changed from gas to liquid; when returning the light intensity of the light signal When the corresponding electric signal changes and the instantaneous change value tends to infinity, the corresponding electric signal is changed at any time before the change Is the light intensity of the return light signal of (a) Corresponding to the electric signal and any time after the change Is the light intensity of the return light signal of (a) When the ratio of the corresponding electric signals is smaller than 1, the medium phase change state of the medium to be measured is changed from liquid to gas; when returning the light intensity of the light signal When the corresponding electric signal changes and the instantaneous change value gradually increases from 0, and at any moment before the change Is the light intensity of the return light signal of (a) Corresponding to the electric signal and any time after the change Is the light intensity of the return light signal of (a) When the ratio of the corresponding electric signals is greater than 1, the medium phase change state of the medium to be measured is changed from solid to liquid; when returning the light intensity of the light signal When the corresponding electric signal changes and the instantaneous change value gradually decreases and approaches 0, and at any moment before the change Is the light intensity of the return light signal of (a) Corresponding to the electric signal and any time after the change Is the light intensity of the return light signal of (a) When the ratio of the corresponding electric signals is smaller than 1, the medium phase change state of the medium to be measured is changed from liquid to solid.
2. The prism-lens-based high polymer optical fiber-based medium phase change state sensing method according to claim 1, wherein the optical fiber ends of the first high polymer optical fiber and the second high polymer optical fiber are aligned and attached to form a right-angle prism end structure, wherein the length of the prism end is 1mm and the width is 2mm.
3. The method for sensing a dielectric phase change state based on a prism lens high polymer optical fiber according to claim 1, wherein the high polymer optical fiber is a high polymer optical fiber with polymethyl methacrylate as a fiber core material.
4. The method for sensing the phase change state of the medium based on the prism lens high polymer optical fiber according to claim 1, wherein the preprocessing of the electric signal converted from the return optical signal comprises the steps of removing high-frequency noise by using a low-pass filter, guaranteeing the accuracy of data, and comparing the real-time measured data change with the standard data change of a database so as to normalize the data result.
5. The method for sensing the medium phase change state based on the prism-shaped high polymer optical fiber according to claim 1, wherein when the medium phase change state of the medium to be measured changes, alarm prompt is carried out, and based on different changes of the medium phase change state, the medium phase change state is prompted by alarm lamps with different colors.
6. A prism-based high polymer optical fiber based medium phase change state sensing system for implementing the method of any one of claims 1-5, comprising: The main control unit is connected with the light intensity data acquisition instrument through a communication connection line and is used for sending instructions to control the light intensity and the wavelength of incident light sent by the light intensity data acquisition instrument, receiving a return light signal transmitted by the light intensity data acquisition instrument, and processing and analyzing the return light signal to obtain a light intensity change curve; The light intensity data acquisition instrument is provided with at least one high polymer optical fiber incident end socket and at least one high polymer optical fiber reflecting end socket and is used for emitting incident light and receiving return light; The high polymer optical fiber incident end socket is used for connecting one end of the first high polymer optical fiber to the light intensity data acquisition instrument; the high polymer optical fiber reflection end socket is used for connecting one end of the high polymer optical fiber II to the light intensity data acquisition instrument; The high polymer optical fiber I is used for transmitting incident light emitted by the light intensity data acquisition instrument and acting on the end head of the prism; The high polymer optical fiber II is used for receiving the return light which is totally reflected at the end head of the prism and transmitting a return light signal to the light intensity data acquisition instrument; The prism end is formed by aligning and attaching the optical fiber ends of the first high polymer optical fiber and the second high polymer optical fiber, so that a right-angle prism end structure is formed and is used for directly contacting a medium to be measured, and the incident light is subjected to total reflection.
7. The prism-based polymer optical fiber medium phase change state sensing system according to claim 6, wherein the main control unit comprises: The preprocessing module is used for preprocessing the electric signal converted by the return optical signal, and comprises the steps of removing high-frequency noise by using a low-pass filter and comparing the real-time measured data change with the standard data change of the database; differential calculation module based on light intensity obtained in real time Differentiating the corresponding electric signal to obtain an instantaneous change value; the ratio calculating module is used for calculating the ratio of the light intensity before and after the change to the electric signal when the light intensity changes, so as to judge the medium phase change state of the medium to be measured; And the display module is used for displaying the light intensity change curve graph.
8. The medium phase change state sensing system based on the prism lens high polymer optical fiber of claim 7, wherein the main control unit further comprises an alarm module for prompting through alarm lamps with different colors when medium phase change states of the medium to be measured are different.
9. The prism-based polymer optical fiber medium phase change state sensing system according to claim 7, wherein the main control unit further comprises a monitoring time setting module for setting a time interval for monitoring the medium to be measured by the system.
10. The prism-lens-based high polymer optical fiber medium phase change state sensing system according to claim 6, wherein the optical intensity data acquisition instrument is provided with 8 high polymer optical fiber incident end sockets and 8 high polymer optical fiber reflecting end sockets, the 8 high polymer optical fiber incident end sockets are respectively connected with 8 high polymer optical fibers I, the 8 high polymer optical fiber reflecting end sockets are respectively connected with 8 high polymer optical fibers II, the 8 high polymer optical fibers I and the 8 high polymer optical fibers II are matched in a one-to-one correspondence manner, so that 8 sets of high polymer optical fiber sensors are formed, and the 8 sets of high polymer optical fiber sensors monitor the same medium to be measured or monitor different mediums to be measured simultaneously.

Description

Medium phase change state sensing method and system based on prism lens high polymer optical fiber Technical Field The invention relates to the technical field of medium phase change state monitoring, in particular to a medium phase change state sensing method and system based on prism high polymer optical fibers. Background The change in phase change state of a medium typically includes a change from a gas to a liquid, a change from a liquid to a gas, a change from a solid to a liquid, a change from a liquid to a solid. Conventional methods typically employ temperature sensors for monitoring. The application provides a method and a system for sensing the phase change state of a medium by capturing the fine change of the refractive index in the phase change process of the medium by utilizing the characteristic that the medium in different states has different refractive indexes. Disclosure of Invention The invention aims to solve the technical problems in the background art, and provides a medium phase change state sensing method and a medium phase change state sensing system based on a prism high polymer optical fiber. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: the medium phase change state sensing method based on the prism lens high polymer optical fiber comprises the following steps: S1, inputting an incident light signal through a first high polymer optical fiber, and enabling an incident angle of the incident light to be larger than a critical angle through a prism end formed by the end parts of the first high polymer optical fiber and the second high polymer optical fiber So that light is totally reflected; The critical angle The calculation formula of (2) is as follows: ; Wherein, the Is the refractive index of the high polymer optical fiber,The refractive index of the medium to be measured; s2, receiving a return optical signal through a second polymer optical fiber; step S3, acquiring the light intensity of the return light signal measured at the time t in real time by a light intensity data acquisition instrument Converting the return light signal into an electrical signal; s4, preprocessing the converted electric signals, and performing sensing judgment on the medium phase change state of the medium to be tested based on the preprocessed signal data; step S5 when the light intensity of the return light signal When the corresponding electric signal changes and the instantaneous change value tends to infinity, the corresponding electric signal is changed at any time before the changeIs the light intensity of the return light signal of (a)Corresponding to the electric signal and any time after the changeIs the light intensity of the return light signal of (a)When the ratio of the corresponding electric signals is greater than 1, the medium phase change state of the medium to be measured is changed from gas to liquid; when returning the light intensity of the light signal When the corresponding electric signal changes and the instantaneous change value tends to infinity, the corresponding electric signal is changed at any time before the changeIs the light intensity of the return light signal of (a)Corresponding to the electric signal and any time after the changeIs the light intensity of the return light signal of (a)When the ratio of the corresponding electric signals is smaller than 1, the medium phase change state of the medium to be measured is changed from liquid to gas; when returning the light intensity of the light signal When the corresponding electric signal changes and the instantaneous change value gradually increases from 0, and at any moment before the changeIs the light intensity of the return light signal of (a)Corresponding to the electric signal and any time after the changeIs the light intensity of the return light signal of (a)When the ratio of the corresponding electric signals is greater than 1, the medium phase change state of the medium to be measured is changed from solid to liquid; when returning the light intensity of the light signal When the corresponding electric signal changes and the instantaneous change value gradually decreases and approaches 0, and at any moment before the changeIs the light intensity of the return light signal of (a)Corresponding to the electric signal and any time after the changeIs the light intensity of the return light signal of (a)When the ratio of the corresponding electric signals is smaller than 1, the medium phase change state of the medium to be measured is changed from liquid to solid. The following is a technical scheme further defined by the method in the invention, and the optical fiber ends of the first high polymer optical fiber and the second high polymer optical fiber are aligned and attached to form a right-angle prism end structure, wherein the length of the prism end is 1mm, and the width of the prism end is 2mm. The following is a technical scheme further defined by th