Journal of Computational & Applied Research in Mechanical Engineering (JCARME)

Articles in Press

Document Type : Research Paper

Authors

¹ Department of ArGEnCo, Research Group Hydraulics in Environmental and Civil Engineering (HECE), Liège University, Liège, Belgium.

² Department of Civil Engineering, Faculty of Engineering, Urmia University, Urmia, Iran

https://doi.org/10.22061/jcarme.2026.8583.2151

Abstract

The occurrence of the cavitation phenomenon in hydraulic structures operating under high flow velocities remains a critical challenge. Efficient mitigation strategies may include increasing air concentration and optimizing the geometric design, such as minimizing sharp changes in flow direction and reducing local vortices. The Seymareh dam bottom outlet, operating under high water heads, is prone to cavitation due to its velocity and pressure fields. This study numerically investigates the effects of geometric modifications on cavitation risk reduction. Results showed that removing lateral expansion increases cavitation indices on outlet walls, while designing a concave curved bed elevates pressure and cavitation indices on the bed surface. Nonetheless, implementing both modifications together completely suppresses cavitation risk. The numerical analysis was conducted under single-phase flow conditions, without considering air entrainment, which, in practice, could further improve outlet safety. These findings could provide useful insights for geometric design approaches to control cavitation in high-velocity hydraulic structures.

Graphical Abstract

Keywords

Main Subjects

Hydraulic and Pneumatic Systems

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Journal of Computational & Applied Research in Mechanical Engineering (JCARME)

Articles in Press, Accepted Manuscript
Available Online from 22 February 2026

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