Chemical Engineering Transactions (Sep 2016)
Consequences of Liquid Jet Breakup Resulting from Interaction with Overpressure Wave from Domino Effect
Abstract
Storage tanks located on industrial sites are potential source term for leakages, followed by various consequences depending on the nature of the commodity: atmospheric dispersion, BLEVE, UVCE, toxic dispersion. Indeed, because of economic and security purposes, chemical substances are stored with different conditions of pressure, temperature and state. This study explores the consequences of a sudden opening of a storage tank due to an external aggression as a consequence from a previous event. Fragmentation of jets and droplets following the trigger event are thus evaluated. Indeed, increasing the exchange surface impacts the evaporation rate and can be an issue in case of toxic or flammable vapor. Laboratory experiments consisted in generating shockwave with an open ended shock tube to breakup liquid droplets with different viscosities. Size of fragmented droplets are optically measured by direct shadowgraphy. Shockwave is measured using both overpressure sensors and Edgerton retroreflective shadowgraphy. In these experiments, secondary breakups of a droplet into an important number of smaller droplets because of the shockwave induced flow are performed. Results are discussed in terms of velocity and size of droplets. Comparisons are made with existing fragmentation models such as Pilch and Erdman (1987) to provide up to date data with situations encountered in industrial risk evaluation.