The third phase of a joint industry project (JIP) on flashing liquid jets and two-phase droplet dispersion was recently kicked off by DNV Software. The aim of the project is to increase the under-standing of the behaviour of flashing liquid jets, and to improve the prediction of droplet atomisation and rainout.

Project management, theory and software development will be carried out by DNV Software, while experimental work will be carried out by Cardiff University (smallscale experiments) and INERIS (largescale butane experiments).

Background
Many accidents involve two-phase flashing releases of hazardous chemicals into the atmosphere. Rainout results in reduced concentrations in the remaining cloud, but can also lead to extended cloud duration because of re-evaporation of the rained-out liquid. For accurate hazard assessment, one must accurately predict both the amount of rainout and re-evaporation of the cloud.