Assessing the Impact of Upstream Hydraulics on the Dose Distribution of Ultraviolet Reactors Using Fluorescence Microspheres and Computational Fluid Dynamics

摘要

The ultraviolet (UV) dose distribution in an UV reactor was evaluated under multiple upstream configurations using UV-sensitive fluorescent microspheres and computational fluid dynamics (CFD). The upstream hydraulics configurations included two orientations of 90-degree bends and one straight pipe inlet. Experimental tests and numerical simulations were performed on a single-lamp low-pressure high-output (LPHO) UV reactor operating at a 50-gpm flow rate and 91% UV transmittance (UVT). Both the numerical and experimental results showed that the straight pipe configuration produced a shift in the UV dose distribution to a higher UV dose range compared to the two elbow configurations. The experimental UV dose distribution displayed no significant difference between the two elbow configurations while a slight difference in the location of the peak was noted between the two elbow configurations for the numerical model. Compared to the experimental results, the CFD model predicted slightly higher reduction equivalent dose (RED) values and higher RED biases. The CFD UV dose distribution displayed taller peaks for all three configurations and higher low UV dose region compared to the experimental distributions.