Coaxial large-scale flow and mixing ratio adjustment injector and using method thereof

The invention discloses a coaxial large-scale flow and mixing ratio adjustment injector and a using method thereof so as to fill the gap that in the prior art, a coaxial large-scale flow and mixing ratio adjustment injector is lacked. The injector comprises a hollow cavity, four propellant inlets, four control valves and one or more composite nozzles; the outer wall of the hollow cavity serves asa shell, and the hollow cavity is internally provided with four mutually-isolated cavities from top to bottom, namely the propellant collecting cavity A, the propellant collecting cavity B, the propellant collecting cavity C and the propellant collecting cavity D; the four propellant inlets, namely the propellant inlet A, the propellant inlet B, the propellant inlet C and the propellant inlet D are formed in the outer walls, adjacent to the shell, of all the cavities from top to bottom correspondingly to serve as inlets for injecting propellants into the corresponding cavities; the four control valves are arranged at