CFD analyses of the Asymmetric Lamp Positioning for the Performance Improvement of a Closed-Conduit UV Reactor

Abstract

CDF analyses for the performance improvement of a closed-conduit ultraviolet (UV) reactor were performed by changing the lamp positions from symmetric to asymmetric. This goal was achieved by incorporating the two performance factors, namely reduction equivalent dose (RED). Four cases were carried out for asymmetirc lamp positioning within the UV reactor chamber and each case consisted of four UV lamps that were simulated once symmetrically and four times asymmetrically. The results of the four asymmetric cases were compared with the symmetric one. Moreover, these results were evaluated by using computational fluid dynamics (CFD) simulations of a closed-conduit UV reactor. Two distinct fluence rate models, namely UVCalc3D and the discrete ordinate (DO) model were employed to validate the simulations results. The simulation results provide detailed information about the model configuration and RED. The RED value was increased by approximately 15% for the UVCalc3D and by 10.5% for the DO fluence rate models. It was concluded that the performance parameters (higher RED) were improved by using asymmetric lamp positioning. The asymmetric lamp positioning can be useful for UV reactor design and optimization.