Abstract:

The absorptive process of laser energy in plasma is simulated by a thermo-chemical non-equilibrium air model which contained 3 temperatures and 11 species. 8 μs after the laser is terminated, the simulation is switched to an equilibrium air model to compute the operating process of a laser propulsion lightcraft. Then influences as laser energy and pulse length on the propulsive performance of the lightcraft are investigated. The results show that when the pulse length is kept equal, impulse coupling coefficient increases along with laser energy increase, while the impulse coupling coefficient increases along with the decrease of pulse length when laser energy is equal. The coupling coefficients for the lightcraft predicted by simulation agree well with those of tests done by Schall.

Key words: aerospace propulsion system, laser propulsion, air-breathing mode, impulse coupling coefficient, numerical simulation