Modeling of diode-pumped cesium vapor laser by combination of computational fluid dynamics and wave-optics

摘要

We have developed a numerical simulation method for diode-pumped alkali lasers (DPALs). We previously reported the use of a simplified gas-flow model, whose adaptability was restricted to forced gas-flow DPALs. In the present study, we have employed an incompressible, three-dimensional computational fluid dynamics (CFD) model. The natural convective flow is modeled using a modified Boussinesq approximation. The results of the simulations were found to be in good agreement with those for a compressible CFD model for a heat-induced flow problem. As a result, good agreement with the experimental results was achieved for a sealed DPAL. On the other hand, the results for the forced gas-flow DPAL were the same as those for the simplified gas-flow model, which confirms the validity of the latter model. The dependence of the beam quality on the pump power for the sealed DPAL was consistent with previously reported results.