The Counter Flow Wet-cooling Tower Thermal Performance Monitoring System And Remote Monitoring Platform Based On CFD

Cooling tower, the most important part of the circulating cooling system, whose cooling performance has critical influence on the effect of the system, needs to be monitored on thermal performance. With the title “The counter flow wet-cooling tower thermal performance monitoring system and remote monitoring platform ”, the thesis studies the counter flow wet-cooling tower thermal performance monitoring model and optimization control method, developes a set of accurate and efficient remote operation of the cooling tower thermal performance monitoring system, to further realize the cooling system of intelligent control, high efficiency and energy saving, which has important practical value for the cooling tower real-time monitoring and remote management. The research is supported by Guangdong CAS Comprehensive Strategic Cooperation Project(2013B091500061).After analyzing the research progress at home and abroad of cooling tower numerical simulation technology, thermal performance monitoring technology, and optimizing control technology, the thesis establishes simulation model of counter flow wet-cooling tower thermal performance based on CFD, then proposes the cooling tower thermal performance real-time and remote monitoring solutions, designs the cooling tower real-time monitor and remote monitoring plateform. Finally, installs and tests the complete set of monitoring system, analyzes the experimental results, and applys it to actual production. Main work of the thesis includes the following parts:⑴Analyzes the modeling mothed of the cooling tower, which is the key part of the cycle cooling system and verify the accuracy of the model through the calculation. By using this model, the cooling tower outlet water temperature under different external environment and operation conditions is predicted.⑵The hardware overall architecture is proposed and all hardware parts of the scene parameter measuring module, executing mechanism module and other key module function is analyzed based on the cooling tower real-time monitotoring functional requirements. According to scene sensing information characteristics of cooling tower, the environment parameters, operation parameters and electrical parameter acquisition module hardware circuit is designed, their working principles, communication modes, and sensor data acquisition processes of the acquisition module hardware are analyzed. In view of cooling tower sensing information acquisition task scheduling requirements, the working mechanism and task process of the central processing module is analyzed, and its key circuit is designed.⑶Each part of software’s overall framework and workflow is analyzed based on functional requirements of cooling tower thermal performance monitoring system. Some sensor datas processing program are researched: temperature compensation and nonlinearity correction of atmospheric pressure sensor data is realized to effectively reduce its temperature drift and nonlinear error. To reduce task conflict and improves the efficiency of the code with task distribution by s cheduler, real-time operating system of central processing module based on μCOS-II is designed. Platform SQL database is designed and cooling tower remote monitoring platform based on Web technology is developed to realize remote management of cooling towe r.⑷Aiming at the heat and mass transfer process of wet cooling tower fill area, cooling tower thermal performance real-time monitoring theory based on Poppe methods is analyzed. On this basis, uses the linear relation of air temperature and water temperature change during the steady process to simplify model and puts forward the cooling tower thermal performance real-time monitoring algorithm based on Temperature Point Boundary Value Measurement(TPBVM); Combined with the energy-saving control demand, puts forward the cooling tower optimal control meth od based on temperature control. The method establishes the relationship between temperature and the flow of the pump by fitting characteristic curve of pump, and then find the the linear relationship between temperature difference and frequency, which greatly simplified the optimization control method; Wet cooling tower thermal performance remote monitoring solution based on Socket technology and SQL technology is put forward to lay the cooling tower thermal performance real-time monitor and remote monitoring platform theoretical foundation.⑸The monitor sensing information acquisition module, monitoring status and system configuration tab of remote monitoring platform function is tested. Then, the cooling tower monitoring experiment is performed and following three results and conclusions is obtain:(1)The output water temperature of the simulation model is very close to the actual experimental values with the relative deviation control within 5%, which proves the accuracy and validity of the model.(2) Cooling tower thermal performance is evaluated using Poppe and TPBVM model respectively, result shows TPBVM model effectively reduces evaluation time about 2.3482 s under the RMSE of 5.48% compared with Poppe model.(3) When the load of cooling tower decreases, the optimal control algorithm based on temperature difference control is used and the results showed that, the measured frequency values is relat ively consistent with the results obtain from the fitted curve equation under different test temperature difference, and the relative deviation is within 3%. When the water temperature difference decreases from 4.8℃ to 3℃, frequency drops, with energy saving rate increases from 15.5% to 78.2%, the energy saving effect of optimizin g control is verified.The counter flow wet-cooling tower thermal performance monitoring system and remote monitoring platform has been used in a company’s cooling tower monitoring project. Running result shows that the monitoring system works and meets the monitoring needs.