Numerical study on kerosene/lox supercritical mixing characteristics of a swirl injector

The turbulent mixing of a kerosene/liquid oxygen coaxial swirl injector under supercritical pressure has been numerically investigated. Three kerosene models are proposed for the kerosene thermodynamic properties. N-dodecene used to replace the kerosene is considered as baseline property for modeling simplicity. Two types of surrogate kerosene are applied. Turbulent numerical model is based on Large Eddy Simulation (LES) with real-fluid transport and thermodynamics; Soave modification of Redlich-Kwong equation of state, Chung's model for viscosity/conductivity, and Fuller's theorem for diffusivity to take account Takahashi's compressible effect. The effect of operating pressure and surrogate kerosene model on thermodynamic properties and mixing dynamics inside an injector and combustion chamber are investigated. To quantify the mixing completeness, mixing efficiency is deliberated. Power spectral densities of pressure fluctuations under various chamber pressures are analyzed.