A gas turbine system includes a fuel nozzle. The fuel nozzle includes a first fluid conduit defining a first fuel passage, a second fluid conduit defining a second fuel passage, and a third fluid conduit defining an oxidant passage. A first plurality of orifices is disposed along the first fluid conduit and is configured to fluidly couple the first fuel passage to the oxidant passage. A second plurality of orifices is disposed on the third fluid conduit and is configured to fluidly couple the second fuel passage to the oxidant passage. A first diameter of the first plurality of orifices is less than a second diameter of the second plurality of orifices.