能量密度对水工质激光推进性能的影响

当辐照激光能量密度不是很高时,在分析水工质激光推进基本物理过程的基础上,只考虑汽化过程对冲量形成过程的贡献,用一维理论模型研究了辐照激光能量密度对冲量耦合系数、比冲、能量转化效率等推进性能参数的影响规律。结果表明,随着辐照激光能量密度的增加,存在一个获得最大冲量耦合系数的最优能量密度;比冲随着能量密度的增加而变大;对于透射率一定的工质而言,随着能量密度增大,能量转化效率趋于一个恒定值。这一理论研究结果对下一步的实验研究工作具有较好的指导意义。

Energy density effects on propulsive characteristics of water propellants for laser propulsion

In the case of low laser energy density,the vaporization process dominates the impulse production compared with other physical processes.One dimensional theoretical model was employed to describe the relationship among energy density and momentum coupling coefficients,specific impulse and the internal efficiency.Theoretical results show that there is an optimum energy density with maximum momentum coupling coefficient.The specific impulse increases with the increase of energy density.For a constant value of transmissivity,the internal efficiency approaches a constant as energy density increases.These theoretical analytical results can be helpful for further experimental works.