Hydrogen Jet Structure in Presence of Forced Co-, Counter- and Cross-flow Ventilation

This paper presents results of experimental investigations on unignited horizontal hydrogen jets in air in presence of co-, cross- and counter-flow. Hydrogen concentration distributions are obtained as functions of distance to the hydrogen release nozzle. The H2-jet variables are two nozzle diameters, 1 mm and 4 mm and two H2-jet mass flow rates, 1 g/s up to 5 g/s. A propeller fan is used to provide forced ventilation, compared to the case with no ventilation three different airflow velocities up to 5 m/s were studied systematically. It was found that any forced ventilation in co-, cross- and counter-flow direction reduces the size of the burnable mixture cloud of the H2-jet compared to a free jet in quiescent air.