Physical modifications to improve a channel’s flow distribution
ABSTRACT A modified approach is suggested to achieve even flow distribution (i.e., the equality of flow distribution) in an open channel in water treatment plant. The suggested approach includes installing
a longitudinal baffle with orifices in the main flow direction. To evaluate the efficiency of suggested model, both computational
fluid dynamics (CFD) model and pilot tests were carried out. The pilot tests, which were scaled down to 1/8 of full scale,
showed that the equalities of the flow distributions in the modified channels were up to 30% higher compared to those in the
conventional channel when the equalities were quantified using the standard deviation of the flow distributions. In addition,
the velocity contours computed by numerical simulation in the conventional full scale channel were compared with the velocity
contours in the remodeled channel in order to verify the more even flow distribution in the modified one than that in the
Key wordsEquality of Flow Distribution–Distribution Channel–CFD (Computational Fluid Dynamics)–Pilot Test
- SourceAvailable from: Sung-Uk Choi[Show abstract] [Hide abstract]
ABSTRACT: The Reynolds stress model is applied to open-channel flows with vegetation. For the computation of pressure-strain term, the Speziale, Sarkar, and Gatski's model is employed. Mellor and Herring's model and Rotta's model are used for diffusion and dissipation rate of Reynolds stress, respectively. Flow structures of open-channels under two vegetative conditions are simulated, namely submerged and emergent plants. Plain open-channel flows are also simulated for comparisons. Computed profiles are compared with the results from the κ-ε model and the algebraic stress model as well as measured data available in the literature. For the plain open-channel flow and the open-channel flow with emergent vegetation, the Reynolds stress model is observed to simulate the non-isotropic nature of the flows better than the algebraic stress model and the κ-ε model. For the open-channel flow with submerged vegetation, it is found that the Reynolds stress model predicts the mean flow and turbulence quantities best compared with the other models. Sediment transport capacity of vegetated open-channel flows is also investigated by using the computed profiles. It is shown that the isotropic turbulence model underestimates the suspended load seriously.Journal of Hydraulic Research 12/2010; 2004(Vol. 42):3-11. · 1.04 Impact Factor
- Water Clarification Process Practical Design and Evaluation..
- Rapid mixing and Flocculation basins, Composite Correction Program for Seoung-nam Water Treatment Plant..