Chaotic cavity design of a UV-C disinfection chamber for uniform radiation distribution.

Abstract

UV-C radiation has been used extensively for disinfection wherein the dosage of radiation varies with the microorganism concerned. The efficacy of disinfection largely relies on the radiation reaching uniformly across the chamber without simultaneously leaving out dark regions within the chamber. The regular geometries of the chambers, such as with circular or rectangular cross sections, invariably lead to hot spots accompanied by regions that remain dark, thereby severely limiting the germicidal effects of the UV-C radiation. We propose and demonstrate the use of a chaotic Bunimovich stadium design chamber that ensures uniform UV-C exposure without any accompanying "dark spots." The design incorporates the shape parameters of a chaotic Bunimovich stadium, wherein ray-tracing simulations confirm the space-filling nature of the photon trajectories, typical of chaotic dynamics. This leads to uniform radiation distribution across the whole volume. Experimental results are presented for a biosafety cabinet that can be used for UV-C disinfection wherein the UV-C light intensity distribution is more evenly distributed than the conventional regular (cuboidal) geometry. Adaptation of this simple design consideration is paramount for air disinfection, wherein dark regions in conventional air ducts can severely compromise the efficacy of the disinfection.