Journal of Water and Wastewater; Ab va Fazilab (in persian)

Journal of Water and Wastewater; Ab va Fazilab (in persian)

Numerical Simulation and Comparison of Four Different UVC-LED Reactor Models for Point-of-Use Water Disinfection Using Computational Fluid Dynamics

Document Type : Research Paper

Author
Saied Moghaddam
Assist. Prof., Dept. of Food Technology, Faculty of Agricultural Technology, College of Agriculture and Natural Resources, University of Tehran, Pakdasht, Iran
10.22093/wwj.2025.517963.3484
Abstract
Drinking water quality and safety are vital factors for public health, and the consumption of contaminated water is one of the main causes of microbial disease transmission. Effective and reliable water disinfection methods at the point of use, especially at the household scale, play an important role in reducing such diseases. This study was conducted with the aim of designing and comparing the performance of four different UVC-LED reactor models for point-of-use water disinfection. To achieve this, Computational Fluid Dynamics was employed to simulate the flow field, mass transfer, and radiation field within the reactors, enabling a detailed assessment of UV distribution and its interaction with the flowing water. In the reactor designs, the influence of internal wall material-specifically polytetrafluoroethylene with diffuse reflectivity and aluminum with specular reflectivity-was investigated to evaluate how surface reflectivity impacts disinfection performance. The results demonstrated that the highest log reduction of Escherichia Coli and the most efficient microbial removal occurred in Reactor Type 4 with an aluminum inner surface, achieving a log reduction of 1.64 and a disinfection efficiency of 30.6%. The findings highlighted that both the reactor geometry and wall material play critical roles in ensuring uniform radiation distribution and enhancing overall disinfection effectiveness. This study offers valuable insights and practical guidance for the optimal design of UVC-LED reactors intended for household and point-of-use applications.
Keywords
Reactor
UVC LED
Water Disinfection
Computational Fluid Dynamics
Point of Use

Subjects

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Journal of Water and Wastewater; Ab va Fazilab (in persian)
Volume 36, Issue 1 - Serial Number 156
March and April 2025
Pages 74-96