Accession Number : AD0867787

Title :   Model Analysis for Inversion Processes in Nonequilibrium Flows. Part II: Steady Flow Model,

Corporate Author : ARMY MISSILE RESEARCH DEVELOPMENT AND ENGINEERING LAB REDSTONE ARSENAL AL PHY SICAL SCIENCES DIRECTORATE

Personal Author(s) : Horton, T. E. ; Cason, Charles

Report Date : 24 NOV 1969

Pagination or Media Count : 46

Abstract : A steady-flow analysis has been made to determine what may be learned about thermal lasers when all rate processes are neglected. The conservation equations of particle continuity and energy for a flowing binary gas were used to estimate upper and lower bounds for optimum temperature conditions for thermal laser operation. Use of the energy levels for the N2-CO2 system showed that a population inversion may be produced about M = 2.35. A thermal efficiency upper bound of 3.7 percent was found for M = 4. For maximizing thermal efficiency, the optimum equilibrium stagnation temperature is not strongly mixture ratio dependent according to this model, and it ranges from 1500 to 1700K for gamma = 1.4. A comparison made between the maximized thermal efficiency for output laser energy between hot CO2 injected into the stagnation region and cold CO2 injected into the expanded supersonic N2 flow shows that downstream injection gives higher efficiencies for constant gamma. The bending mode of CO2 has little effect on the results obtained for near optimal conditions. The model suggests that adding a species to deactivate frozen lower laser levels can increase the expected output power by an amount limited to the molar ratio of N2 to CO2 when this ratio is greater than unity. (Author)

Descriptors :   (*GAS LASERS, MOLECULAR ENERGY LEVELS), GAS FLOW, THERMAL PROPERTIES, NITROGEN, CARBON DIOXIDE, EFFICIENCY.

Subject Categories : Lasers and Masers

Distribution Statement : APPROVED FOR PUBLIC RELEASE