Gas quenching dry slag granulation process is an energy-saving environmental protection method for waste utilization and waste heat recovery of molten slag, and the molten slag is broken up by supersonic airflow into droplets in this process. This paper performed the numerical investigations on the breakup behavior of slag by the coupled level-set and volume of fluid (CLSVOF) methodology and gain a deep insight into the breakup mechanism of the primary breakup and influence of gas Weber number (We) and liquid Reynolds number (Re) on the primary breakup. The results indicated that the primary breakup include flat film breakup and spherical cap film breakup, the both are typical perforation breakup; Aerodynamic force cause K-H (Kelvin Helmholtz) instability, K-H surface waves are the root cause of film breakup; The wavelength and the film thickness decrease with increasing We which is conducive to reducing the ligament diameter; The wavelength and the film thickness decrease first and then increase with increasing Re which is optimum in the range of 1068–1280; The empirical formula of the ligament diameter is obtained. The ligament diameter decrease with increasing airflow velocity and slag density and increase with increasing slag mass flow rate and slag viscosity.

气淬干渣制粒工艺是一种利用废渣和回收废渣的节能环保方法，在此过程中，超声波气流将熔渣分解成液滴。本文采用液位和体积耦合（CLSVOF）方法对炉渣的破碎行为进行了数值研究，并对初次破碎的破碎机理以及气体韦伯数（We）和液体的影响有深入的了解。雷诺数（Re）。结果表明，初次破裂包括平面膜破裂和球形帽膜破裂，二者均为典型的射孔破裂。空气动力导致KH（Kelvin Helmholtz）不稳定，KH表面波是薄膜破裂的根本原因；波长和膜厚随着We的增加而减小，这有利于减小韧带直径。波长和膜厚先减小，然后随Re的增加而增加，这在1068–1280的范围内是最佳的。得到了韧带直径的经验公式。韧带直径随气流速度和炉渣密度的增加而减小，而随炉渣质量流量和炉渣粘度的增加而增大。