A numerical model for simulating the fluid dynamics following rupture in pressurised pipeline networks containing multi-component hydrocarbon mixtures is described. Based on the solution of the conservation equations using the method of characteristics, the model accounts for pipeline bends, branches and couplings. Modelling of hypothetical full bore ruptures in straight and branched pipelines indicate the importance of accounting for pipeline system configuration complexity when Simulating Such type of failure. (c) 2005 Elsevier Ltd. All rights reserved.