Air-shielded fuel injection assembly to facilitate reduced NOx emissions in a combustor system

A mixer assembly for use in a combustion chamber of a turbine engine, the assembly comprising:

• a mixer including a main housing and defining an annular cavity;
• an air-shielded fuel injection assembly in fluid communication with the annular cavity, the air-shielded fuel injection assembly comprising:
• a plurality of fuel injection ports, each fuel injection port configured to inject a fuel radially outward into the annular cavity to introduce a fuel column extending radially outward into the annular cavity;
• and
• a plurality of air injection ports, each air injection port formed upstream of an associated fuel injection port and wherein each air injection port is separated from the associated fuel injection port by a distance, each air injection port configured to inject a flow of air radially outward into the annular cavity and upstream of the plurality of fuel injection ports, to introduce an upstream air curtain extending radially outward into the annular cavity and upstream of an associated fuel injection column, and
• a swirler positioned upstream from the air-shielded fuel injection assembly and having a plurality of vanes for swirling air traveling through the swirler.

A turbine engine assembly comprising:

• a compressor section;
• a combustor section;
• and
• a turbine section, wherein the compressor section, the combustor section and the turbine section are configured in a downstream axial flow relationship, the combustor section comprising:
• a combustion chamber;
• and
• a mixer assembly disposed in the combustion chamber, the mixer assembly comprising:
• a mixer including a main housing and defining an annular cavity;
• an air-shielded fuel injection assembly in fluid communication with the annular cavity, the air-shielded fuel injection assembly comprising:
• a plurality of fuel injection ports, each fuel injection port configured to inject a fuel radially outward into the annular cavity to introduce a fuel column extending radially outward into the annular cavity;
• and
• a plurality of air injection ports, each air injection port formed upstream of an associated fuel injection port and wherein each air injection port is separated from the associated fuel injection port by a distance, each air injection port configured to inject a flow of air radially outward into the annular cavity of the mixer assembly and upstream of the plurality of fuel injection ports, to introduce an upstream air curtain extending radially outward into the annular cavity and upstream of an associated fuel injection column introduced by an associated fuel injection port of the plurality of fuel injection ports;
• and
• a swirler positioned upstream from the air-shielded fuel injection assembly and having a plurality of vanes for swirling air traveling through the swirler and provide an upstream swirl crossflow.