Computational fluid dynamics application in modeling and improving the performance of a storage reservoir used as a contact chamber for microorganism inactivation

This study explored the use of computational fluid dynamics (CFD) modeling approach to simulate two tracer studies conducted, in scaled-down physical models of an existing storage tank, to investigate the effect of tank configuration on the effective contact time (t₁₀). One of the scaled-down physical models, of the storage tank, was equipped with one baffle wall at the middle length and the other was equipped with nine baffle walls distributed evenly along the reservoir length. A comparison between the experimental and modeled tracer concentration profiles showed an excellent agreement. The developed CFD model was then applied to different reservoir configurations for further investigation towards achieving t₁₀ improvement. The use of seven small inlets and nine baffle walls resulted in extending the t₁₀ from about 8 min to about 30 min (for a theoretical detention time, τ , of 32 min). Furthermore, using fewer baffle walls with different inlet arrangements enhanced the t₁₀. Key words: microorganism inactivation, disinfection, computational fluid dynamics (CFD), modeling, effective contact time, storage reservoir hydraulics.