The Effect of Netting Dissipaters on Increasing the Efficiency of Energy Dissipation in Vertical Drops

Abstract:

Abrupt changes of the channel bed elevation in hydraulic systems, e.g. in chutes, drops and steeped spillways, results to create a sever flow kinematic energy. This excess energy, can tend to different phenomena, such as tremendous forces, scouring and degrading the channel bed, resulting to destruction of the downstream hydraulic structures. The most important source to cause this phenomena is the the existence of sequent vertical drops along the the channel. In this study, the energy dissipation efficiency was increased by installing a new type of dissipaters namely netting dissipater on the crest of the vertical drops based on model experimtation. Also, the features of hydraulic jump, created in the stilling basin, were compared to those of a simple vertical drop. By assembling the above mentioned structure to the top of the stilling basin, the jet flow direction is changed, the degree of turbulence is increased and as the results, the kinematic energy loss increases and the length of the hydraulic jump decreses. The enhanced efficiency of the proposed structure was quantified based on the achieved experimental data.

• Periodical: Applied Mechanics and Materials (Volumes 90-93)
• Pages: 2427-2430
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.90-93.2427
• Online since: September 2011
• Authors: Elham Bakhshian, Abdorreza Kabiri-Samani
• Keywords: Energy Dissipation, Netting Dissipater, Stilling Basin, Vertical Drop

References

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DOI: 10.1080/00221689509498578

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