비 가시 환경에서의 적외선 열화상 카메라 가시도

In this paper, the visibility test results of thermal infrared cameras under dense fog environments are described. When a severe accident occurs in a nuclear power plant, cold water is ejected downward to cool the reactor pressure vessel through the nozzle of the core spray system. When this cold water collides with the hot reactor structures, dense aerosol (fog) is formed, severely diminishing the visibility in the reactor containment building where the reactor pressure vessel is located. It is impossible to acquire critical, such as water level, reactor pressure, temperature, and gamma ray dose rate, through image interpretation using a CCD/CMOS camera system based on visible (400-700 nm) wavelengths. As an alternative to the CCD/CMOS camera, we consider the thermal infrared camera based on the NWIR (3-5 um) or LWIR (7-14 um) wavelength spectrum. To test the monitoring performance of the thermal infrared camera under dense fog environments, we created a test facility (2.5 m × 2.5 m × 15 m, WHD) into which fog was injected until the concentration of the fog was saturated. The hot plates including the heating source were located at far (~ 10 m) and near (~ 3 m) positions inside the test facility. The thermal infrared camera monitored the hot plates, which were 3-10 m away, under the dense fog environment. We compared the detection performance of the thermal infrared camera with the monitoring perfromance of the CCD camera under the same visibility conditions.