Optimization of Venting Units to Minimize the Dimensions of Explosive Zones

This contribution investigates how changes of standardized venting geometries affect the EX zone extension. CFD simulations are used to explore different venting unit geometries in order to reduce the experimental effort. The optimization of the venting unit geometries is analyzed separately from the dispersion of the hydrogen–air mixture into the atmosphere. The decisive parameters to minimize the EX zone that are to be influenced by changing the lambda venting unit geometry are, the outlet velocity and, the outlet mass fraction of hydrogen at the outlet of the venting unit. In order to obtain the smallest possible EX zone, the velocity at the outlet and the hydrogen mass fraction at the outlet must be as low as possible. To achieve this, the geometry of the lambda venting unit is modified to minimize these parameters.