Analysis of explosion consequences using CFD tools

AGUSTÍN ALEJO D´ALESSANDRO; STELLA M. TONELLI

Buenos Aires

Conferencia; 6th LATIN AMERICAN CONFERENCE ON PROCESS SAFETY; 2014

CCPS-AICHE

In this paper the overpressure due to the shock wave from an explosion is simulated using CFD tools. In particular, the software FLUENT® (ANSYS) is used to perform all the 2D simulations presented. We discuss alternatives to include boundary conditions programmed by the user, since FLUENT allows the user to enter C code as User-Defined Function (UDF). Using these capabilities, the initial pressure profile of the blast is introduced as time-varying boundary conditions.To show the behavior of blast waves, two cases are developed. In the first example, the shock wave produced by a primary vessel explosion hits a second vessel that resists the impact. In this case it is possible to observe effects such as the overlapping pressure waves between the primary and the second vessel (due to the wave rebound in the second vessel). The ?shadow effect? behind the second vessel can be also seen. The second case presents the same shock wave hitting and breaking a pipe in the second vessel. This equipment failure leads to domino escalation involving the dispersion of a toxic substance.