Study on Hydraulic Performance of Modular Constructed Wetlands based on Baffle Optimization

Rong Hao; Zhonggou Chen; Guoyi Zhang

doi:10.6919/ICJE.202605_12(5).0023

Authors

Rong Hao
Zhonggou Chen
Guoyi Zhang

DOI:

https://doi.org/10.6919/ICJE.202605_12(5).0023

Keywords:

Modular Constructed Wetlands; Numerical Simulation; Flow Field Distribution; Hydraulic Characteristics; Structural Optimization Design.

Abstract

This study addresses the severe clogging, challenging construction quality control, and high maintenance costs associated with traditional constructed wetlands by exploring structural optimization approaches for modular constructed wetlands (MCW). To gain an intuitive understanding of the internal flow patterns within modular constructed wetlands, a three-dimensional CFD simplified porous medium model was developed using FLUENT software. To further optimize the hydraulic efficiency of the modular wetland system, the impact of baffle arrangement on overall hydraulic performance was systematically investigated. Nine baffle configuration modes were compared in simulations, revealing that a configuration with two inner baffles represented the optimal solution: it achieved a flow field uniformity index of 0.68, an effective volume ratio of 0.815, a hydraulic efficiency of 0.792, and a fluid dispersion coefficient of merely 0.028. Increasing the number of baffles or concentrating them inward significantly degraded the flow field, resulting in a hydraulic efficiency of only 0.441 for a configuration with four inner baffles. This study validates the effectiveness of CFD-based structural parameter optimization, providing a quantitative theoretical foundation and practical technical solutions for efficient, standardized design of modular constructed wetlands.

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