Analytical and computational indoor shelter models for infiltration of carbon dioxide into buildings: Comparison with experimental data

Abstract

This paper describes two indoor shelter models – an analytical model and a Computational Fluid Dynamics (CFD) model - that can be used to predict the level of infiltration of carbon dioxide (CO2) into a building following a release from an onshore CO2 pipeline. The motivation behind the development of these models was to demonstrate that the effects of shelter should be considered as part of a Quantitative Risk Assessment (QRA) for CO2 pipeline infrastructure and to provide a methodology for considering the impact of a CO2 release on building occupants.A key component in the consequence modelling of a release from a CO2 pipeline is an infiltration model for CO2 into buildings which can describe the impact on people inside buildings during a release event.This paper describes the development of an analytical shelter model and a CFD model which are capable of predicting the change in internal concentration, temperature and toxic load within a single roomed building that is totally engulfed by a transient cloud of gaseous CO2. Application of the models is demonstrated by comparison with experimental measurements of CO2 accumulation in a building placed in the path of a drifting cloud of CO2. The analytical and CFD models are shown to make good predictions of the average change in internal concentration. Furthermore, it is demonstrated that the effects of shelter should be taken into account when conducting QRA assessments on CO2 pipelines.