Nitrogen Bubble Type Water Level Gauge And Design Of Monitoring Software System

Due to ever increasing development of coast lines, estuaries and flood plains, the need for precision monitoring of the water levels in these areas becomes ever more critical. Because when a river overflows in a vast flood plain, a minute rise in the water level represents extremely large volume of water. The basic requirement, which improving the accuracy of flood prediction, predicting flood routes and controlling flood, is precision measurement of water level. Through Modem nitrogen bubble type system transmit data to computer, which is connected with computer and data logger via PTSN, results in lab showed system accuracy up to millimeter.First of all, according to theory of nitrogen bubble type water level gauge, this paper selected to measure water head using nitrogen bubble type system to minimizing effects of freezing and water corrosion. Adopting travel wave filter technique, it eliminates signal of gravity wave using gas transmission line as wave filter, take through tide of low frequency and wind current signal. At the same time it analyzed the principle in detail which system can provide accurate water level data free from noise of waves and sampling processes. Then it introduced operational principle of the system and gross design, lay emphasis on the introduction of communication protocol of software and illustrate communication module, DAO module. At last, it gave debug results of this system and put forward the application in other aspects.Monitoring software includes communication detection, preference setting, graph displaying etc. It can correct water level value automatically to assist hardware up to technical indicators of water level gauge. It fulfilled auto-acquisition of water level data, storage, transmission, graph display, editing preferences, alarm etc. It demonstrated from run results that the monitoring software gives users an interfacefriendly, convenient manipulation and complete functions.