Combustor for gas dynamic laser

A method of operating a cylindrical gas dynamic laser combustor to obtain stable efficient soot-free combustion with uniform temperature and species profiles at the entrance to a laser nozzle array including the steps of,

• (1) forming a combustion zone having an L/D ratio of 3 or greater;
• (2) premixing an oxidizer and fuel to provide a uniform fuel-oxidizer mixture and injecting it into said zone from its forward end;
• (3) providing a residence time of the injected fuel and oxidizer equal to or greater than 0.014 seconds in said zone;
• (4) injecting an oxidizer at the end of said zone at a secondary injection plane in the opposing direction to the injection of the injected fuel and oxidizer for forming an opposing oxidizer flow field where the primary zone combustion products and the secondary oxidizer start mixing;
• (5) sizing a mixing zone downstream of the secondary injection plane to provide a residence time equal to or greater than 0.020 before the mixing process enters the nozzle array.