Analysis of ventilation systems subjected to explosive transients: initial analysis and proposed approach. [Deflagration; detonation; transition from deflagration to detonation]

Abstract

This report describes our initial study of explosive pressure transients and their propagation through ventilation systems. The objective of this study is to organize the required calculations into a computer code that is highly useroriented and will predict explosive-induced gas dynamics within a ventilation system. The explosive process is subdivided into three regimes-deflagration, detonation, and transition from deflagration to detonation. Equations describing each process and suggested procedures for solving these equations are presented. The proposed organization of the explosion code capitalizes on the desirable aspects of the previously developed TVENT code, which predicts tornado-induced pressure transients within ventilation systems. The explosion code will include both near-and far-field analyses. The near-field analysis will use detailed models to describe the combustion process near the explosive event, and provide parametric driving potentials for flow in the regions that are removed from the explosive event (far-field). The fa^-field analysis will include the combustion wave as it propagates through the rest of the system.

Analysis of ventilation systems subjected to explosive transients: far-field analysis

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