Development Of On-line Thermal Performance Monitor&Remote Monitoring Platform For Wet Cooling Tower

Cooling tower Monitoring is the premise of improving cooling tower efficiencyand stabilization of cooling system. With the title “Development of On-line ThermalPerformance Monitor and Remote Monitoring Platform for Wet Cooling Tower”, thethesis studies the models and methods of wet cooling tower thermal performancemonitoring. A monitoring system, which could accurately monitor cooling towerthermal performance in on-line and remote control ways are developed. It haspractical significance for cooling tower on-line monitoring and networked remotemanagement. The research is supported by Guangdong SME Innovation Fund(2012CY166) and New Century Excellent Researcher Award Program from Ministryof Education of China (NCET-08-0211).The thesis first analyses the research progress at home and abroad of coolingtower models, monitoring technology, and remote monitoring technology, thenproposes the cooling tower thermal performance and remote monitoring solutions,designs the cooling tower on-line monitor and remote monitoring plateform. Finally,installs and tests the complete set of monitoring system, analyzes the experimentalresults. Main work of the thesis includes the following parts:⑴Aiming at the heat and mass transfer process of wet cooling tower fill area,cooling tower thermal performance on-line monitoring theory based on Merkel,e-NTU, and Poppe methods is analyzed. On the basis of the classical model, linearrelation of air temperature and water temperature change and simplified model of thecooling tower thermal performance is built; cooling tower thermal performanceon-line monitoring algorithm based on Temperature Boundary Value MeasurementConstraints (TBVMC) is presented; wet cooling tower thermal performance remotemonitoring solution based on Socket technology and SQL technology is put forwardto lay the cooling tower thermal performance on-line monitor and remote monitoringplatform theoretical foundation.⑵The hardware overall architecture is proposed and all hardware parts of thesensing information acquisition module and central processing module function isanalyzed based on the cooling tower on-line monitotoring functional requirements.According to field sensing information characteristics of cooling tower, theenvironment 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 schedulingrequirements, the working mechanism and task process of the central processingmodule is analyzed, and its key circuit is designed.⑶Each part of software’s overall framework and workflow is analyzed based onfunctional requirements of cooling tower thermal performance monitoring system.Some sensor datas processing program are researched: temperature compensation andnonlinearity correction of atmospheric pressure sensor data is realized to effectivelyreduce its temperature drift and nonlinear error; piecewise linear processing andsoftware filter of temperature sensing data is implemented to reduce its nonlinearerror and improve its anti-jamming ability to improve measurement data AD codevalid resolution by2~3bits. To reduce task conflict and improves the efficiency of thecode with task distribution by scheduler, real-time operating system of centralprocessing module based on μCOS-II is designed. Platform SQL database is designedand cooling tower remote monitoring platform based on Web technology is developedto realize remote management of cooling tower.⑷The monitor sensing information acquisition module, central processingmodule of monitor, monitoring status, and system configuration tab of remotemonitoring platform function is tested, and the testing report is concluded. Front andback interface board circuit and sticker of the monitor are designed to make themonitor chassis and assemble the monitor, and monitoring system is installed in thefiled. Finally, the cooling tower monitoring experiment is performed which proves allmeasurement datas are accurate. Cooling tower thermal performance is evaluatedusing Merkel, e-NTU, Poppe, and TBVMC model respectively, result showsTBVMC model effectively reduces evaluation time about2.2244s under the RMSE of5.89%compared with Poppe model.The cooling tower thermal performance on-line monitor and remote monitoringplatform has been used in a company’s cooling tower monitoring project. Runningresult shows that the monitoring system works and meets the monitoring needs.