Abstract: An example injector includes a first conduit defining a first flow path including a first choke for a first fluid and a second conduit defining a second flow path including a second choke for a second fluid. The second choke is defined by a converging region upstream and a diverging region downstream of the second choke. The example injector further includes a mixing region after both the diverging region of the second flow path and the first choke and configured to receive the first fluid the second fluid, and an outlet configured to allow the first fluid and the second fluid to exit the mixing region. The first and second chokes are configured to allow a constant mass flow of the first and second fluids, respectively, to flow into the mixing region independent of a pressure at the outlet.