Author(s): Seyedmehdi Mohammadizadeh; Jose Gilberto Dalfre Filho; Edevar Luvizotto Junior; Andre Luiz Bortolacci Geyer And Thomaz Eduardo Teixeira Buttignol

Linked Author(s):

Keywords: Cavitation; Cavitation erosion; Orifice diameter; Standoff distance; Nozzle geometry; Cavitation jet apparatus; Submerged water jet; High-Performance Concrete (HPC)

Abstract: This study investigates the effects of key parameters on cavitation-induced erosion, aiming to improve the understanding and assessment of material resistance in hydraulic systems. Cavitation erosion significantly impacts the durability and efficiency of hydraulic components. To address the need for reliable testing methods, a sensitivity analysis of a cavitation jet apparatus (CJA) was conducted using a vertical cylindrical test tank, a submerged nozzle, and an aluminum sample. Results showed that smaller orifice diameters, particularly 2 mm, led to intensified erosion, with the highest impact at a standoff distance (SoD) of 5 cm. Among tested nozzle geometries, a 132° conical sharped-edges nozzle combined with these parameters caused the most severe erosion. In contrast, chamfered edge nozzles and a commercial nozzle (MEG2510), as well as an SoD of 10 cm or more, exhibited reduced erosion. Building on this analysis, the study further evaluated cavitation erosion on concrete specimens, offering insights for assessing concrete components in hydraulic structures, such as spillways. Comparative analysis of seven High-Performance Concrete (HPC) types revealed that HPC compositions incorporating Nano-silica and Micro-silica, Micro-silica alone, or Carbon Micro exhibited superior resistance to cavitation-induced erosion. Standardizing the testing duration to 1200 s demonstrated the CJA's reliability in evaluating material resistance. By establishing a relationship between pressure, impact forces, and erosion severity, this research underscores the CJA's utility in designing more durable hydraulic systems.

DOI: https://doi.org/10.64697/978-90-835589-7-4_41WC-P1972-cd

Year: 2025