Radiation modeling of microplasma UV lamps for design analysis and optimization

Abstract

Microplasma UV lamps have recently emerged as viable excimer-based sources of UV radiation, garnering significant attention during the recent COVID-19 pandemic for their use in disinfection applications because of their ability to emit human-safe far-UVC (200–240 nm) spectrums. An accurate model to simulate the radiation profile of microplasma UV lamps is of paramount importance to develop efficient microplasma lamp-implemented systems. We developed a 3D numerical model of microplasma UV lamps using the ray optics method. The simulation results for lamp irradiance and fluence rate were experimentally validated with standard optical radiometry and actinometry measurements, respectively. To improve the optical efficiency of microplasma lamps, an in-depth analysis of radiation behavior inside the standard commercially available lamp was performed using the geometrical optics method, and several potential scenarios were explored. A 2D modeling of an individual microcavity indicated that the current common lamp design can be significantly improved by preventing radiation loss, and small modifications in optical design can greatly increase the energy performance of the system. Based on the findings of this study, several virtual design concepts were proposed, and their performances were numerically compared with that of the original design of commercial microplasma lamps. The developed model can potentially be integrated with hydrodynamic and kinetic models for the virtual prototyping of complex photoreactors operating with UV microplasma lamps.