Experiment and Three-Dimensional Simulation of Gas-Centered Swirl Coaxial Injector Spray

Abstract

On the basis of experiments at atmospheric pressure, a three-dimensional simulation study of the spray pattern and breakup mode of gas-centered swirl coaxial (GCSC) injector was conducted with the RNG k-ε model. The gas-liquid interface was captured by the adaptive mesh refinement (AMR) technique, coupled level-set and volume of fluid (CLSVOF) method. The results demonstrated that when the liquid mass flow rate (ṁ1) is constant, the ejection action of the central airflow is enhanced along with the gas mass flow rate (ṁg). The internal and external pressure difference of the liquid film increases and the spray angle decreases. Meanwhile, the flow characteristics were analyzed. When ṁg is constant, the radial velocity and tangential velocity of the liquid film at the injector outlet increase with ṁ1, which may result in the increase of the spray angle. According to the gas-liquid mass flow rate (GLR), the breakup modes of spray are divided into the perforation breakup, bubble breakup and pneumatic breakup.

Keywords

• gcsc injector
• three-dimensional simulation
• spray morphology
• breakup mode
• glr