Avizonis P V, Hogge C B, Butts R R, Kenemuth J R
Appl Opt. 1972 Mar 1;11(3):554-64. doi: 10.1364/AO.11.000554.
Thermal blooming is considered for the cases of with and without wind transverse to the beam propagation from the point of view of fluid dynamics of a compressible gaseous system and the coupling of this with geometric optics using eikonal formalism. Full compressible fluid dynamic relationships are developed (first-order perturbation approximation) with kinetics of energy relaxation from vibrational levels into heat and with thermal conductivity of a compressible gas as a heat loss mechanism. Eikonal theory is examined from the point of view of paraxial treatmen t in rigorous form, and some analytical beam intensity relationships are derived. In the process, several questions on the formation of caustics and thick lens effects are resolved. As a consequence of the above, a general time dependent model for the interaction of a laser beam with a compressible absorbing medium in the presence of wind is developed, and certain time dependent analytical solutions are obtained. These solutions reduce to the plain hermal blooming case with no wind and for long times to steady state wind case that has been previously reported by others to various degrees of correctness [F. G. Gebhardt and D. C. Smith, Appl. Phys. Lett. 14, 52 (1969); D. C. Smith, IEEE J. Quantum Electron. QE-5, 600 (1969)].
从可压缩气体系统的流体动力学以及使用程函形式将其与几何光学耦合的角度，考虑了横向于光束传播方向有风与无风情况下的热晕效应。建立了完整的可压缩流体动力学关系（一阶微扰近似），其中包括从振动能级到热的能量弛豫动力学以及可压缩气体的热导率作为热损失机制。从严格形式的傍轴处理角度研究了程函理论，并推导了一些解析光束强度关系。在此过程中，解决了关于焦散形成和厚透镜效应的几个问题。基于上述结果，建立了一个在有风情况下激光束与可压缩吸收介质相互作用的一般时变模型，并获得了某些时变解析解。这些解在无风情况下简化为普通热晕情况，在长时间情况下简化为先前其他人已在不同程度上正确报道过的稳态风情况[F. G. 格布哈特和D. C. 史密斯，《应用物理快报》14, 52 (1969)；D. C. 史密斯，《IEEE量子电子学杂志》QE - 5, 600 (1969)]。
