Bissonnette L R
Appl Opt. 1973 Apr 1;12(4):719-28. doi: 10.1364/AO.12.000719.
A mathematical model of the thermally induced nonlinear propagation of a laser beam in an absorbing fluid medium is developed. The theory includes, identifies, and clearly assesses the relative importance of the different regimes due to conduction, free convection, and/or forced convection cooling. The derived equations of propagation explicitly account for the diffraction effects and permit a straightforward estimate of their relative influence with respect to the thermal distortion. More specifically, similarity parameters or scaling laws are deduced from the governing equations. There is a total of five of these parameters, but it frequently happens in practical applications that the actual number is reduced to only one. Finally, sample numerical results are presented to illustrate some of the implications connected with the proposed model, and the qualitative agreement with published experimental data is very gratifying.
建立了激光束在吸收性流体介质中热致非线性传播的数学模型。该理论涵盖、识别并清晰评估了传导、自由对流和/或强制对流冷却等不同机制的相对重要性。推导得到的传播方程明确考虑了衍射效应，并能直接估计其相对于热畸变的相对影响。更具体地说，从控制方程中推导出了相似参数或标度律。这些参数共有五个，但在实际应用中，实际数量常常减少到只有一个。最后，给出了样本数值结果，以说明与所提出模型相关的一些影响，并且与已发表实验数据的定性一致性非常令人满意。
