Increasing chemical efficiency by mixing different buffer gases on COIL

To improve the output power and chemical efficiency,a new method is put forward,which requires no notable change in the configurations and uses different gases as buffer gas.Some experiments are done on chemical oxygen-iodine laser (COIL) with an 11.7 cm gain length.When N2,Ar and CO2 are used as the primary and secondary buffer gases,change of the average molecular weight promotes the mixing between the primary and secondary gases.Experimental results confirm the possibility of improving the chemical efficiency.When N2 is used as the primary gas and Ar as the secondary gas,the highest output power and chemical efficiency are obtained as 3.09 kW and 30.2％.