Experimental Study on Impulse Coupling Coefficient of Laser Thruster

摘要

The impact pendulum is a simple and credible test to measure the impulse of laser thrusters when coupled with a Laser Supported Detontation (LSD). The principles of the measurement and estimating of test error are discussed. Six parabolic nozzles were studied with different parameters of a generatrix equation. Experiments were carried out with a range of different laser energies. The relationship of the impulse coupling coefficient to incident laser energy and geometrical factors of nozzle design were discussed. It was found that the value of impulse coupling coefficient depends largely on the incident laser energy and nozzle design. The optimum distance between inner surface of the nozzle and ignition zone varies with the incident laser energy. The impulse coupling coefficient achieved by nozzles with a point focus is higher than that obtained by those with a round focal zone.