A photocatalytic reactor was simulated through computational fluid dynamics (CFD) with surface reaction for trichloroethylene (TCE) oxidation at various pollutant concentrations, flow rates, and reactor lengths. The results were compared with those from experiments. The experimental work involved using a differential photoreactor for kinetics studies and an annular flow photoreactor for overall removal investigations under various conditions. The modeling predictions agreed closely with the experimental data within the range in which results were examined. The modeling results indicated significant radial TCE concentration gradient and nonuniform flow distributions in the annular photoreactor. CFD was applied to predict the performance of a number of UV photocatalytic reactor design concepts, to study the impacts of some design parameters on the reactor efficiency. The modeling results demonstrated that under similar flow rate conditions, the thickness of the contaminated air layer flowing over the photocatalyst surface could substantially influence the reactor performance. Thinner contaminated air layers provided more uniform radial concentration distribution of TCE and improved the reactor performance. (c) 2005 American Institute of Chemical Engineers.