A Radiometric Water-Level Monitoring System in a High-Pressure Steam Chamber and its Error Analysis

A study is conducted on a newly designed radiometric monitoring system for detecting the water level in a high-pressure steam chamber that can be used to monitor the high-pressure boiler operation state in a power plant. The principle of this system is based on recording the rate of gamma radiation (¹³⁷Cs) that goes through the boundary between the steam and the water and then calibrating the rate into the actual level with computer processing. A practical mathematical model and a special buildup factor family for this calibration are provided. A particular treatment of errors for this application is given. This system, which has been used in a power plant for more than 30 months and has worked smoothly, has a relative accuracy of 1.5% and has long-term reliability.