关键词: 高金属含量水冲压发动机；点火；燃面温度；多相耦合计算；点火药

Abstract: To exactly simulate the flow filed characterization and burning surface temperature during ignition，based on the Navier-Stokes equations，where mass，momentum and energy transported to the gas flow filed from the fuel or igniter were respectively transformed into the corresponding conserved quantity governing equation source items in specific computation grids，which imply the first column grids adjacent to the fuel surface for fuel and the igniter coverage grids for the latter，and where molten magnesium detached from the burning surface were converted as the magnesium droplets injected from the combustion chamber inlet. A multi-phase turbulent combustion/flow simulation coupling fuel combustion，igniter combustion and motor chamber flow together for water-ramjet with Mg mass percentage of 73% was accomplished. Affection to fuel combustion between different ignition powders named black powder and boron/potassium nitrate were analyzed. Reliable ignition and continuous burning could be approached by igniter with 40g black powder and 0.5kg/s water injection，and the final burning surface temperature keeps steady at 943K. This temperature could be higher achieved by boron/potassium nitrate than black powder of the same mass，but the prior one simultaneously calls for more time to establish steady state.

Key words: High-metal-based water ramjet；Ignition；Burning surface temperature；Multi-phase simulation；Ignition powder