Frozen soil area heat pipe working condition data detection device based on temperature difference method
Technical Field
The invention relates to the technical field of frozen soil engineering equipment detection, in particular to a frozen soil area heat pipe working condition data detection device based on a temperature difference method.
Background
The frozen soil is soil body and rock with negative temperature and ice, and the area of the frozen soil in China is mainly distributed in Qinghai-Tibet plateau, great and small Khingan mountains in northeast China, tianshan mountain and Altaishan mountain. Along with the continuous acceleration of national economic construction, various traffic facilities such as Qinghai-Tibet highways, qinghai-Tibet railways and other national important projects are continuously built in the special areas.
Due to the existence of permafrost and thick-layer underground ice, the stability of the foundation of the transmission line tower in the permafrost region has great uncertainty: along with the change of external environment, the melting of ice in frozen soil can lead to the rapid weakening of the foundation of the tower, and the safe operation and the long-term stability of the foundation of the tower are greatly affected. To avoid this effect, a certain number of heat pipes are typically arranged around the foundation to maintain the stability of the foundation.
A heat pipe is a heat conduction system with two-phase convection circulation of vapor and liquid, which is a sealed vacuum steel pipe filled with extremely volatile liquid and gaseous working media (such as nitrogen, freon, propane, CO2 and the like), the upper end is a heat dissipation section provided with heat dissipation fins, and the lower end is a heat absorption section. When the heat pipe is applied, the heat absorption section of the heat pipe is inserted into frozen soil which needs to be cooled. When the ambient temperature, namely the temperature of the radiating section is lower than the temperature of the underground heat absorption section, the heat pipe starts to work in a heat conduction state, and the heat in the foundation soil is continuously radiated to cool the soil body.
Therefore, any minor flaw or damage of the heat pipe during the manufacturing, installation and use process can cause the leakage of the internal working medium, thereby affecting the working efficiency of the heat pipe and even being scrapped. Therefore, it is an important task to detect whether the heat pipe is operating properly. In the existing detection means, a detector is usually required to hold the instrument until the working heat pipe is collected and analyzed in the later period, the working period of the heat pipe is generally a low-temperature night environment in winter, and the working is stopped due to the fact that the heat is absorbed by solar radiation and the heat radiation section of the heat pipe is heated in the daytime. Namely: to obtain effective working condition data, the detection period is limited to the night in winter, and the low temperature in winter or the darkness in night is unfavorable for the development of the detection work; in addition, the surface temperature of the heat pipe, the stability of the radiation temperature and the difference value from the ambient temperature can be changed to a large extent due to the influence and interference of various conditions such as the ambient temperature, the wind speed, the solar heat radiation and the like and the difference of the working performance and the state of different heat pipes. The method has the advantages that the thermal parameters and the working conditions of the heat pipe are difficult to measure, so that the detection result obtained by the later analysis has large error and low precision.
For example, for a heat pipe of a power transmission line tower foundation, the following difficulties exist in the expansion of the work of detecting the working condition data: 1. compared with linear engineering such as roads and railways, the power transmission line tower footing is generally erected at a certain distance from the roads or at a position which is far away from the roads by a great distance, and under the condition of extreme cold regions such as Qinghai-Tibet plateau, the road traffic is difficult, and particularly the road traffic is difficult to reach at night, so that the method is time-consuming and labor-consuming. 2. The limited sight line at night is not beneficial to accurately finding the heat pipe: (1) The transmission line iron tower and the heat pipe are made of metal materials, the heat pipe is embedded close to the foundation of the tower, and the heat pipe and the transmission line tower are mutually overlapped in the observation sight range, so that serious interference is caused; (2) Under the condition of low temperature in the middle night, the tower material and the heat pipe metal material all show the same thermal infrared property, and cannot be detected by using the existing method.
Disclosure of Invention
The invention aims to solve the technical problem of providing a frozen soil area heat pipe working condition data detection device based on a temperature difference method, which can automatically measure heat pipe working condition data and ensure the accuracy of measured data, thereby improving the detection efficiency and the accuracy of detection results.
In order to solve the existing problems, the invention provides a frozen soil area heat pipe working condition data detection device based on a temperature difference method, which comprises a protective shell, an infrared temperature sensor, an internal thermometer and a data memory, wherein the infrared temperature sensor, the internal thermometer and the data memory are arranged in the protective shell; the data memory is connected with the infrared temperature sensor, the internal thermometer and the external thermometer and is used for recording and storing measurement data from the infrared temperature sensor, the internal thermometer and the external thermometer; and a detection hole is formed in the position, opposite to the detection direction of the infrared temperature sensor, of the protective shell, so that the infrared temperature sensor can directly measure the pipe wall temperature of the heat pipe.
Preferably, heat dissipation holes are formed in the upper portions of two sides of the protective shell.
Preferably, the fixing device is specifically a magnetic body arranged on one side, close to the heat pipe, of the inner side of the protective shell.
Compared with the prior art, the invention has the following advantages:
1. the accuracy of the detection result is high
(1) A novel detection mode is established
The heat pipe is a metal round pipe, and the curved surface, the metal heat conduction property and the like of the heat pipe bring a plurality of difficulties to accurately test the thermal parameters such as the surface temperature, the heat flow and the like of the heat pipe under the extreme natural conditions of a cold region. The invention establishes a semi-open and semi-closed detection environment by utilizing the protective shell, so that the detection is not interfered by the external environment (except an external thermometer), the temperature detection problem of the metal surface is well solved by high-precision and thermal infrared temperature observation, and the accuracy of measurement data is ensured; meanwhile, the protective shell indirectly plays a role in heat flow detection, and the heat radiation intensity of the heat pipe under different environmental conditions can be obtained through the comparative analysis of the internal temperature and the external temperature in the later period.
(2) Ensuring the integrity and accuracy of the detection result
The invention is provided with the infrared temperature sensor and the internal and external thermometer, which can detect the temperature of the pipe wall of the heat pipe and also detect the internal and external environmental temperature of the shell, thus being convenient for judging the working state of the heat pipe by comparing and analyzing the relative environmental temperature of the surface of the heat pipe in the later stage, and further improving the accuracy and the reliability of the detection result obtained by the later stage analysis.
The automatic detection breaks through the limitation of the existing detection period, and improves the working efficiency
(1) Changing the working condition of heat pipe detection
The invention is provided with the fixer and the data memory, the detection device can be fixed on the heat pipe in daytime, and the detection device can automatically measure and record the measured data, and then the measured data can be obtained. Compared with the prior art, the night manual in-person detection method has the advantages that the safety of detection personnel is ensured, and meanwhile, manpower and material resources are saved.
(2) The key detection problem of the heat pipe of the transmission line is solved, and the maintenance engineering is safe and stable
The invention adopts the contact sensor, can realize the rapid detection without damaging the heat pipe under the original state of the heat pipe, and only needs to fix the detection device on the surface of the heat pipe during the detection. The device has small volume and light weight, and can be carried in a large quantity, so that a plurality of heat pipes can be detected simultaneously, and the technical problem that once the heat pipes are well distributed, the heat pipes cannot be detected accurately and in a large scale is fundamentally solved.
The invention integrates infrared and temperature detection, ensures that the heat pipe can be accurately and automatically detected to quickly and accurately judge whether the heat pipe is abnormal or not in the later period, so that the abnormal heat pipe can be timely maintained or replaced, and further provides guarantee for the safe operation of engineering facilities such as power transmission line towers and the like in frozen soil areas protected by the heat pipe.
Drawings
The following describes the embodiments of the present invention in further detail with reference to the drawings.
Fig. 1 is a schematic cross-sectional view of the present invention.
FIG. 2 is a schematic diagram showing the relative positions of the heat pipe to be tested in the application of the present invention.
FIG. 3 is a perspective view showing the appearance of the present invention
In the figure: 1-protective shell, 2-infrared temperature sensor, 3-internal thermometer, 4-data memory, 5-external thermometer, 6-detection hole, 7-heat-dissipating hole, 8-magnetic body and 9-heat pipe.
Detailed Description
As shown in fig. 1 to 3, a temperature difference method-based device for detecting working condition data of a heat pipe in a frozen soil area comprises a protective shell 1, an infrared temperature sensor 2, an internal thermometer 3 and a data memory 4 which are arranged in the protective shell 1, an external thermometer 5 arranged outside the protective shell 1 and a fixer arranged on the protective shell 1, wherein the detection device is used for fixing the detection device on the heat pipe 9. The infrared temperature sensor 2, the internal thermometer 3 and the external thermometer 5 are connected to the data memory 4 via transmission cables, which periodically transmit the respective measured data to the data memory 4, which data memory 4 records and stores them.
When the device is used, the detection device can be fixed on the heat pipe 9 in the daytime, so that the detection device can automatically execute detection work, and after a period of time, for example, in the daytime of the next day, a detection person takes out stored data for later indoor analysis and judgment of the working condition of the heat pipe. It will be appreciated that one skilled in the art can determine which of these are valid operating condition data, i.e., data measured while the heat pipe 9 is in an operational, thermally conductive state, by observing the extracted measured data.
A detection hole 6 is formed in one side, close to the heat pipe 9, of the protective shell 1, and is used for detecting the pipe wall temperature of the heat pipe 9 by the infrared temperature sensor 2, and the pipe wall of the heat pipe 9 is positioned at the position of the detection hole 6 in use; the upper parts of the two sides of the protective shell 1 are provided with heat dissipation holes 7, so that the whole device can be ventilated and dissipated. In the actual manufacturing process, the protective housing 1 can be made of PVC, opaque organic glass or metal and other materials capable of shielding wind and rain and shielding the sun, for example, a PVC plate with the thickness of 0.3mm is made into a cuboid with the thickness of 10cm multiplied by 5cm multiplied by 3cm to be used as the protective housing 1, square holes with the side length of 1.5mm multiplied by 1.5mm are formed in the middle part of one surface of 10cm multiplied by 5cm to be used as the detection holes 6, and a plurality of round small holes are formed in the other two sides of the protective housing 1 to be used as the heat dissipation holes 7.
The infrared temperature sensor 2 is arranged at a position, which is far away from the heat pipe 9 and is opposite to the detection hole 6, inside the protective shell 1, the detection direction of the probe faces the heat pipe 9, and the temperature of the pipe wall of the heat pipe 9 is directly detected in an irradiation mode during operation.
The fixing device may be a magnetic body 8 disposed on one side of the inner side of the protective housing 1 near the heat pipe 9, and may integrally adsorb the detection device on the pipe wall of the heat pipe 9, and may be four magnets disposed on four corners of the inner side of the protective housing 1. Of course, it is also possible to use binding strips separately provided on both sides of the protective case 1 or other fixing objects capable of fixing the entire detection device to the heat pipe 9.
In the actual assembly process, the internal thermometer 3 can be arranged at an upper position inside the protective shell 1, generally above the infrared temperature sensor 2; an external thermometer 5 is arranged below the outside of the protective shell 1; finally, the data memory 4 is arranged in the lowermost part of the interior of the protective housing 1 and is connected to the infrared temperature sensor 2, the internal thermometer 3 and the external thermometer 5 by means of transmission cables.
The detection device integrates infrared and temperature detection, has the effects of simple and convenient operation, rapid retraction, continuous detection parameters, automatic observation and the like, and (1) can accurately measure the thermal infrared temperature of the outer surface of the metal pipe with high precision through the construction of a semi-open, relatively stable airflow and light-shielding detection environment, namely a detection chamber; (2) By detecting the internal temperature and the external temperature of the protective shell 1 at the same time, key data can be provided for analysis of heat release efficiency and working conditions of different heat pipes under different environmental temperature conditions; (3) The invention has the automatic recording efficiency of the detection data, and can carry out long-term observation records at different time intervals according to the setting; (4) According to the system analysis of the overall and actually measured big data on site, the establishment of the judging modes of the working characteristics of different heat pipes can be established, and the identification and judgment of the working states of different heat pipes can be completed according to the continuous recorded data of the different heat pipes, so that data support is provided for the repair and replacement of the heat pipes.