Abstract:
The transmission path of vibration difficult to determine has posed a great threat to the safe operation of water transmission pipeline, due mainly to the complex structure of pump station pipeline, where there are many vibration sources. In this study, an attempt was made to analyze the pipeline transfer path characteristics of pumping stations using transfer entropy. The pipeline of 7 pump stations in an irrigation area was also taken as the research object. Firstly, a prototype test was carried out to obtain the spectrum diagram, and energy proportion, thereby analyzing the main vibration source of pipeline vibration. Then, a transmission entropy method was used to identify the vibration transmission path of the main vibration source in the pump station pipeline under various working conditions. The effectiveness of the pipeline vibration transmission path was finally verified when taking the information transmission rate as the quantitative standard. The results show that: 1) The main vibration source was caused by the blade frequency and frequency doubling in the pipeline, mainly transmitting from the elbow and tee pipe to other parts when the pumping station unit operated stably. Furthermore, the average information transmission rate was 27.2%. More importantly, the transmission rate was relatively low during stable operation, mainly because the anchor block, buttress, and other devices played a critical role in the vibration reduction and energy dissipation. 2) The main vibration source was also caused by the blade frequency in the pipeline, mainly transmitted from the elbow and tee to other parts of the pipeline, when the pump station unit starting up. The average information transmission rate was 42%. It was found that a large part of the energy at the elbow and tee was transmitted to other parts of the pipeline during startup. 3) The main vibration source was the high-frequency vibration caused by low-frequency water flow pulsation and pipe water coupling in the pipeline when the pump station unit was shut down. The vibration was mainly transmitted periodically between the valve, elbow, and tee. The average information transmission rate was 51.4%. It can be seen that a large part of the energy from the valve, elbow, and tee was transmitted to other parts of the pipeline. Correspondingly, the information transmission rate of each working condition showed that a large part of vibration energy at the pipeline valve, elbow, and tee pipe was still transmitted to other parts. Whether the machine was switched on or off, the energy transmitted by the pipeline during the stable operation was less under the control of vibration reduction measures, such as anchor block. Therefore, the prototype observation data was selected to analyze the source of vibration through the spectrum diagram and energy proportion, where quantitatively determine the transmission relationship between vibration from the perspective of energy with the help of transmission entropy and information transmission rate, as well as the direction of vibration transmission. It was more efficient and intuitive than before, indicating great advantages in the application of vibration transmission path recognition. Consequently, this research can greatly contribute to accurately identify the vibration transmission path of the main vibration source in the pump station pipeline, thereby identifying the dangerous parts of the pipeline under different working conditions, where the vibration reduction measures can be further proposed. This finding can provide a promising theoretical basis for the operation and management of the pump station pipeline