Implementing an experimental program for model validation of initial velocity in aerosol jets

The accidental release of pressure liquefied gases which form aerosols is an area of interest in assessing safety hazards in the chemical processing industries. The failure of a vessel or pipe in the form of a small hole can result in the formation of an aerosol jet. When a liquid stored under pressure above its normal boiling point is suddenly released to atmospheric pressure, superheating of the jet results. Due to the thermodynamic instability associated with superheating, the behavior of the jet in the region near the orifice exit is not well understood.;The initial velocity of an aerosol jet is the principle determinant of the dilution of the jet with air. An overestimate of the velocity can result in an overestimate of air entrainment. The initial velocity is also used to determine the maximum stable droplet size in the jet based on mechanical break-up modeled with the Weber number. The goal of this research was to improve dispersion model predictions for the extent of flammability hazards associated with aerosol releases by providing a better prediction of de-pressurized jet velocity.;A model was proposed to predict the initial velocity in an aerosol jet based on liquid storage conditions. An experimental program was designed and implemented in order to validate this velocity prediction. A series of small-scale flashing water jets was studied using Laser Doppler Velocimetry (LDV) to measure the droplet velocity in the jet. The proposed model was shown to more accurately predict the initial velocity in the flashing water releases than another widely used model for velocity estimation.