Hydraulic characteristics of flow through angled baffle-plates in an open channel

ABSTRACT

This paper aims to study the flow characteristics through angled baffle-plates in an open channel. The experiments were conducted in a self-circulating hydraulic flume with three designated baffle-plates’ angles (30°, 60°, and 90°) and three flow conditions (high, medium, and low). Results showed that all the designed angles for the different flow conditions do retard the flow resulting in reduced downstream mean discharge as compared to without the baffle-plates. The baffle-plates installed at 90° showed the greatest percentage of mean discharge reduction for all the flow conditions (ranged between 5.32% and 11.67%) as compared to 60° (ranged between 3.96% and 8.3%) and 30° (ranged between 3.55% and 7.07%). An equation to predict the relative flow depth increase due to the retarding behaviour of the angled baffle-plates structure was also developed in this study using multiple linear regression. The proposed equation has an R² value of 0.69, $R_{\mathrm{a}\mathrm{d}\mathrm{j}}^2$ value of 0.62, Mallow’s C_p value of 2 and a mean square error (MSE) value of 0.4548, which is the best among all the possible regression models for this study. The equation can be used by the designer in determining the desired angle for the baffle-plates structure to prevent overflow at upstream of the structure.

KEYWORDS:

• Angled baffle-plates
• detention
• flow regulator
• mean discharge reduction
• relative flow depth increase
• stormwater management

Acknowledgements

The authors would like to thank Universiti Malaysia Sarawak for providing the facilities as well as the equipment for this study.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by Universiti Malaysia Sarawak under the Special Grant Scheme [grant number F02/SpGS/1542/2017].