Abstract: Direct onset detonation initiated by high temperature jets from a pre-combustion tube is investigated numerically. A dispersion-controlled dissipative scheme is adopted to solve Euler equations with axis-symmetric flows implemented with detailed chemical reaction kinetics of the hydrogen-oxygen mixture. For validation and verification purpose, computational results are compared with experimental results. Three regimes of direct detonation initiation, referred to as supercritical, critical and subcritical ones, are demonstrated with numerical analyses from a viewpoint of chain reactions. The regimes are affected by the PDEs geometric configuration. It is recognized that the SWACER mechanism plays an important role in the state transit of chemically reacting flows in which the gradient of chemical radicals presents properly.

Key words: PDE, jet initiation, direct detonation initiation, detonation, numerical simulation