New analysis method for radiation modeling and sterilization effect of UVC-LED module

Abstract

With the growing application of deep ultraviolet light-emitting diodes (UVC-LEDs) in water treatment, it is important to simulate the significance of modeling their output for designing UV reactors becomes crucial. In this study, we design a UVC-LED package module by 4 chips and set two different total optical powers, which are 8 mW and 12 mW respectively, and each chip wavelength is 280 nm, and the radiation distribution is simulated. Next, the irradiance uniformity under different radiation distances is discussed, and the bactericidal effect is qualitatively analyzed under different environmental mode settings. We found that as the radiation distance becomes larger, the irradiance values decrease, but evenly distributed on the petri dish. In addition, regardless of the optical power level of chips, probably in the range of the petri dish radius of 15 mm or more, the smaller the radiation distance is set, the irradiance is even smaller than those irradiance was set under bigger radiation distance; within 15 mm, the radiation distance is less, the irradiance drops sharply, which means that close-range radiation is not suitable for large-area sterilization, although the average irradiance and local irradiance are improved at this time, they are only concentrated under the light source, and there is a large blind zone in the edge region. If the pathogenic microorganisms used in water are sterilized, it is necessary to fully stir the near-aqueous microbial culture solution to achieve full sterilization. What’s more, if highly resistant pathogenic microorganisms want to achieve high-efficiency bactericidal effect, only continuously to increase the total optical power of the UVC-LED chips, set a close radiation distance as possible and stir the culture solution. Through the simulation of the radiation distribution of the model and the analysis of actual situation, we can evaluate the bactericidal effect of the model in the real environment. It will be a feasible and worthy advocate method of analyzing bactericidal efficacy for the rational design of the future UVC-LED model.