DEVELOPMENT OF A MODEL FOR SIMULATING THE VARIABILITY OF THE PHYSICAL-PROPERTIES OF SUBSTANCES, STORED IN VARIOUS STORAGE TANKS, IN THE PRESENCE OF AN EXTERNAL HEAT-SOURCE

In this paper a mathematical model for simulating the variability of t he physical properties of substances stored in various storage devices (pressurised or cryogenic tanks etc.), in the presence of an external heat source, is presented. Design/construction characteristics includ ing tank geometry, and all possible safety features (safety valves, li quid pump out, water deluge systems, water curtains, fire walls, exter nal cooling by fixed or mobile fire fighting applicances) are taken in to account in the model formulation. As an application example the cas e of an ammonia cryogenic storage tank is examined. In this example he at input arises from an adjacent storage tank being on fire and the ti me dependence of pressure and temperature of the tank and its content properties are calculated. The modular design of the model and the pro mising results allow the inclusion of the model developed in other mor e complicated packages (e.g., DOMINO) in order to simulate accident ev olution sequences in parallel with various operational interventions o r additional safety features.