Experimental Study of Jet-Formed Hydrogen-Air Mixtures and Pressure Loads From Their Deflagrations in Low Confined Surroundings-Paper

To provide more practical data for safety assessments, a systematic study of explosion and combustionprocesses which can take place in mixtures produced by jet releases in realistic environmentalconditions is required. The presented work is aimed to make step forward in this direction bindingthree inter-connected tasks: (i) study of horizontal and vertical jets, (ii) study of the burnable cloudsformed by jets in different geometry configurations and (iii) examination of combustion and explosionprocesses initiated in such mixtures. Test matrix for the jet experiments included variation of therelease pressure and nozzle diameter with the aim to study details of the resulting hydrogenconcentration and velocity profiles depending on the release conditions. In this study the followingparameters were varied: mass flow rate, jet nozzle diameter (to alter gas speed) and geometry of thehood located on top of the jet. The carried out experiments provided data on detailed structure forunder-expanded horizontal and buoyant vertical jets and data on pressure loads resulted fromdeflagration of various mixtures formed by jet releases. The data on pressures waves generated in theconditions under consideration provides conservative estimation of pressure loads for realistic leaks.