中文摘要：

采用计算流体力学方法,在考虑液氮物性变化以及液氮与磨料颗粒相互作用的基础上,模拟液氮磨料射流流场,并分析液氮射流对磨料颗粒的加速效果。结果表明：在相同喷嘴压降下,液氮磨料射流不仅具有比磨料水射流更高的射流速度和颗粒速度,而且能够在壁面上产生与水射流相当的射流冲击效果;液氮射流能够对颗粒产生较好的加速效果,最大颗粒速度随着喷嘴压降和喷嘴直径的增加而增大,随着颗粒直径的增加而降低;围压和颗粒初始速度对最大颗粒速度影响极小,在工程应用中可以忽略不计。

英文摘要：

Abrasive particles can be added into liquid nitrogen to form an abrasive liquid nitrogen jet （ ALNJ ） for rocking breaking. In this study, the flow behavior of the ALNJ was studied using the computational fluid dynamics method, considering the properties of liquid nitrogen and its interactions with abrasive particles. The acceleration effect of liquid nitrogen on particles was analyzed. The results show that, at the same nozzle pressure drop, the abrasive liquid nitrogen jet not only has greater jet and particle velocities than water jet, but also displays an equivalent jetting impact effect on the targeted wall. The liquid nitrogen jet can generate excellent acceleration effects on particles, and the maximum particle velocity increases with the increase of the nozzle pressure drop and nozzle diameter, but decreases with the increase of particle diameter. Confining pressure and initial particle velocity have little effect on particle acceleration, which can be neglected in the design of the ALNJ process.