Ah experimental and theoretical study of a Monodisperse spray

An investigation in the recirculating flow region downstream of a centerbody monodisperse fuel injector has been performed. Experimental measurements of gas temperature, axial velocity, and turbulent kinetic energy as well as drop size and velocity have been obtained for n-heptane. A two-dimensional two-phase computer model has utilized these measurements as inlet and outlet gas phase boundary conditions as well as spray Inlet conditions to predict both the gaseous flowfield and droplet behavior. A comparison between predicted and measured gas phase velocities shows excellent agreement. The momentum exchange between the two phases is demonstrated as relative drop velocity (drop velocity minus gas velocity) decreases with axial distance. Using the d² law for droplet evaporation, the calculated evaporation coefficient, β, under- predicts the measured value by thirty percent, corresponding to a four percent overprediction of drop size.