A Numerical Simulation of Spray Characteristics in Swirl Coaxial Injector with Varying Recess Length

Abstract

The main objective of this research is determining the spray characteristics of an injector for varying recess length according to the spray conditions. Swirl coaxial injector is used to obtain improved atomization and mixing efficiency due to their wide spray cone angle and excellent combustion efficiency. The turbulent mixing of water and nitrogen swirl injector is systematically tested under cold flow condition. To study this effect numerical study was conducted on a 3D model with varying recess length. A grid study has been used to find the quality of the result. Volume Of Fluid multiphase model is used to simulate the flow inside a swirl injector. This simulation is carried out with the conservation of mass, momentum and energy has been used. The implicit scheme available in the Volume Of Fluid (VOF) model is used to calculate the interface representation between phases. Two turbulence model RNG k-ε and RSM is compared with the experiment data to determine which turbulence is good. The numerical results are compared with both RNG k-ε and Reynolds Stress Model where Reynolds Stress Model is found to be satisfactory with the experimental data of spray angle. A five recess length case is tested for the mixing of the oxidizer and fuel, to find out external and internal mixing in it.