E.V. Maslennikova - JSC «GSKB Almaz-Antey named after A.A. Raspletin», Moscow
M. A. Ogar - JSC «GSKB Almaz-Antey named after A.A. Raspletin», Moscow. E-mail: mogar@inbox.ru

At the gas-dynamic carbon dioxide laser (GDL) optimization stage, the anomalous power decreasing was registered. Practically the same effect was registered at the supersonic flow carbon monoxide laser (SCML). The analysis showed that losses (radiation absorption) at nonactive cavity zones influence on output power decreasing. The work purpose was studying of dynamic influence of losses at nonactive cavity zones on output power time dependence in supersonic flow gas lasers, and searching its reduction method. It is established that the edge jets in GDL flows in nonactive cavity zones. Gas stagnation and its heating happen. It leads to increasing of low laser level thermal population, and to radiation absorption. To explain this fact, it was made the analytic model that takes into account the major effects in GDL cavity. It is shown that the results of experimental and calculation investigations are in a good agreement. Bringing the cocurrent nitrogen jets into the edge nozzles was technically realized for proofing nonactive cavity zones from flowing carbon dioxide molecules over there. It led to removal of output power decreasing and holding down on its maximum level. As well as in GDL, in SCML the edge jets also flows in nonactive cavity zones. It leads to gas heating to stagnation temperature. On its own gas heating does not lead to radiation absorption, in contrast with GDL, but the heated vibrationally excited gas has a significant absorption. To estimate influence of absorption in nonactive zones of SCML, the computation of multiple-pass cavity was made. It is shown that total output power decreasing, accounting its spectral distribution, achieves 50%. To avoid the significant output power decreasing in SCML, it is necessary to bring the cocurrent nitrogen jets at the edge zones of supersonic gas flow, as it was made in GDL. Also it is promising to organize nitrogen boosting at nonactive cavity zones.