by David W. Johnson
Abstract
The RELEASE model is a significant step forward in the prediction and modeling of superheated liquid releases. The RELEASE model was the end result of a multi-year research program sponsored by the Center for Chemical Process Safety. RELEASE computes the amount of vapor, aerosol, and liquid produced when a superheated, pressurized liquid is released into the atmosphere. RELEASE takes into account many of the variables that are known to affect the amount of each of these releases, such as the amount of superheat, the velocity of release, the physical properties of the material released, etc.
RELEASE was developed to model horizontal releases of pure components. The model does not take into account droplet vaporization during the release trajectory. A second shortcoming of the model is its restriction to pure components. Since many superheated releases involve mixtures, the usefulness of the model is limited. This paper discusses how the RELEASE model can be improved to include the effects of droplet evaporation during the release trajectory. Comparison of the RELEASE model calculations to experimental data, with and without the RELEASE enhancements, will be presented. In addition, a method for handling the thermodynamics of mixtures will be outlined.