CFD-Based Numerical Simulation and Optimization of a Chlorine Contact Tank Compartment

Numerical simulation has recently been widely applied across various industries for analysis and optimization purposes. Owing to its capability to accurately simulate three-dimensional flow fields and to post-process multiple parameters in detail, it provides deep insight into complex physical phenomena. In this study, numerical simulation is employed to perform three-dimensional fluid flow analysis, optimize residence time, and eliminate local dead zones in the east compartment of one of the thirteen chlorine contact tanks in Tehran. A user-defined scalar (UDS) is developed to account for the residence time associated with each inlet. Although general information is available regarding the effect of different baffling arrangements on the baffling factor, existing standards primarily address chlorine contact tanks with a single inlet. In real operational conditions, however, chlorine contact tanks may include multiple inlets and outlets due to operational constraints, as is the case for the reservoir investigated in this study. Because different inlets may operate at different flow rates, calculating the residence time corresponding to each inlet becomes impractical using conventional approaches. In this research, CFD simulations are utilized to evaluate the residence time associated with each inlet while considering the effects of columns, separation baffles, and turning baffles. Through geometric optimization, a new configuration is proposed that enhances the required CT value for effective Giardia inactivation.

کلیدواژه ها:

CFD ، Chlorine contact tank ، Residence time ، Disinfection ، Free Chlorine residual