Theoretical, numerical, and experimental investigation of pressure rise due to deflagration in confined spaces

Estimating pressure rise due to deflagration in a fully or partially confined space is of practical importance in safety design of a petrochemical plant. Herein, we have developed a new theoretical model to predict the pressure rise due to deflagration in both fully and partially confined spaces. First, the theoretical model was compared and validated against experimental data from the closed-space experiments with hydrogen, methane, propane, and ethane. The theory predicted accurate pressure rises near the stoichiometric regime for all fuel types; outside the stoichiometric regime, especially, for rich mixtures of hydrocarbons with air, the theory over-predicted pressure rise since it does not account for soot formation and the associated energy losses by radiation. Experimental investigation of propane and hydrogen deflagration was conducted in a partially confined space and the theory-based predictions agreed with the data up to 5%. Parametric numerical study was performed to investigate the effect of the initial pressure and temperature of gaseous fuels on pressure rise.