Investigation into the Ignition Process of Hydrogen Jet in Air

摘要

The paper is aimed at the investigation of the ignition process of supersonic jet in air based on experiments and numerical simulations. The experiments were conducted in a closed, air filled tube (at 1 bar) where high pressure hydrogen (70 - 150 bar) was injected through the nozzle of various diameters, and with various obstacle geometries in front of the jet. The obstacle in front of the jet was aimed at the induction of hydrogen ignition. Numerical simulations were performed with KIVA3V code with 2D axisymmetrical geometry of experimental setup. Experiments proved that hydrogen ignition does not take place within the whole shock tube volume but may be present only locally. Computations showed that hydrogen jet ignition is possible by diffusive ignition or reflected shock wave ignition mechanism. The number of performed simulations allowed to determine the accurate initial hydrogen pressure and geometry of the flow at which ignition takes place.