VENTED GAS DEFLAGRATION MODELING - A SIMPLIFIED APPROACH

Starting from a detailed mathematical model previously developed, which accounts for each physicochemical phenomenon involved in a vented deflagration process, a simplified (or short-cut) model has been derived based on suitable assumptions and algebraic manipulations. The simplified model reduces to a system of three ordinary differential equations, the solution of which can be readily achieved on a small personal computer. The reliability of such a simple model has been tested by comparison with a collection of published experimental data (the same one considered when developing the original detailed model), covering a wide range of values for vessel volume (0.001-199 m3), initial pressure (0.1-0.4 MPa), and bursting pressure (0.1-2.96 MPa) and including various vessel shapes and fuel-air compositions. The error in the maximum absolute pressure values, averaged over 91 experimental data relative to vented explosions, is equal to 28%. The proposed model can be regarded as a simple tool for predicting with reasonable accuracy the maximum pressure value during a vented deflagration in a wide range of operating conditions, thus providing a significant contribution to the venting area design.