Impingement capability of high-pressure submerged water jet:Numerical prediction and experimental verification
来源期刊：中南大学学报(英文版)2015年第10期
论文作者：LIU Hai-xia SHAO Qi-ming KANG Can GONG Chen
文章页码：3712 - 3721
Key words：submerged water jet; cavitation; shear effect; impingement test; micro hardness; surface morphology
Abstract: At jet pressures ranging from 80 to 120 MPa, submerged water jets are investigated by numerical simulation and experiment. Numerical simulation enables a systematic analysis of major flow parameters such as jet velocity, turbulent kinetic energy as well as void fraction of cavitation. Experiments facilitate an objective assessment of surface morphology, micro hardness and surface roughness of the impinged samples. A comparison is implemented between submerged and non-submerged water jets. The results show that submerged water jet is characterized by low velocity magnitudes relative to non-submerged water jet at the same jet pressure. Shear effect serves as a key factor underlying the inception of cavitation in submerged water jet stream. Predicted annular shape of cavity zone is substantiated by local height distributions associated with experimentally obtained footprints. As jet pressure increases, joint contribution of jet kinetic energy and cavitation is demonstrated. While for non-submerged water jet, impingement force stems exclusively from flow velocity.
LIU Hai-xia(刘海霞)1, SHAO Qi-ming(邵启明)1, KANG Can(康灿)2, GONG Chen(龚辰)2
(1. School of Material Science and Engineering, Jiangsu University, Zhenjiang 212013, China;
2. School of Energy and Power Engineering, Jiangsu University, Zhenjiang 212013, China)
Abstract:At jet pressures ranging from 80 to 120 MPa, submerged water jets are investigated by numerical simulation and experiment. Numerical simulation enables a systematic analysis of major flow parameters such as jet velocity, turbulent kinetic energy as well as void fraction of cavitation. Experiments facilitate an objective assessment of surface morphology, micro hardness and surface roughness of the impinged samples. A comparison is implemented between submerged and non-submerged water jets. The results show that submerged water jet is characterized by low velocity magnitudes relative to non-submerged water jet at the same jet pressure. Shear effect serves as a key factor underlying the inception of cavitation in submerged water jet stream. Predicted annular shape of cavity zone is substantiated by local height distributions associated with experimentally obtained footprints. As jet pressure increases, joint contribution of jet kinetic energy and cavitation is demonstrated. While for non-submerged water jet, impingement force stems exclusively from flow velocity.
Key words:submerged water jet; cavitation; shear effect; impingement test; micro hardness; surface morphology
