EXPERIMENTAL-DETERMINATION OF THE DROPLET SIZE AND VELOCITY DISTRIBUTIONS AT THE EXIT OF THE BOTTOM DISCHARGE PIPE OF A LIQUEFIED PROPANE STORAGE TANK DURING A SUDDEN BLOWDOWN

In 1991, the Commission of the European Communities launched a series of projects specifically aimed at the understanding of chemical hazard s. This was called the STEP Program and covered projects on hazard ana lysis to determine the consequences of releases of flammable pressuriz ed and liquefied gases. In that frame, the present study concerns the experimental determination of the droplet size and velocity distributi ons within a jet at the exit of a discharge pipe of a liquefied propan e storage tank during a sudden blowdown. For this purpose, a Phase Dop pler Particle Analyzer (PDPA) was used to measure liquid drop size and velocity. Due to the high drop concentration in the jet, it was neces sary to protect the incident laser beams and the light scattered by pa rticles to make the measurements possible. In such conditions, a set o f blow-downs was performed by varying the nozzle diameter, the initial pressure inside the storage vessel and the measurement position in th e jet, These tests include on- and off-axis measurements. The results are presented, showing the droplet evaporation and the velocity evolut ion inside the jet. This work provides original data which can be usef ul for the validation of vapour cloud dispersion codes. Copyright (C) 1996 Published by Elsevier Science Ltd.