Large Eddy Simulations (LES) of Supercritical Nitrogen Jets

A detailed numerical study of a supercritical nitrogen jet injected in supercritical environment is presented in this paper. Current work studies the mixing behaviour of jet by conducting a 3D simulation using CFD code OpenFOAM. Turbulence closure for this problem is obtained by LES model which solves the full transport equation for larger-scale turbulence. The Peng–Robinson equation of state is used along with a volume translation method for accurate prediction of thermodynamic properties near critical point. A new solver is developed for studying transcritical and supercritical turbulent flows in OpenFOAM. Performance of this solver is validated with results from literature and used in present study. The paper further investigates effects of injection pressure on jet spreading behaviour by visualizing the density gradient and vorticity field near the injector. It is noticed that spreading behaviour is largely dependent on pressure. Current work highlights these impacts and their underlying mechanics.