Abstract: A system and method for operating a gas turbine engine are provided. The system and method remove fuel from a fuel manifold during a low-power mode of operation of the gas turbine engine. The method includes supplying fuel to a combustor of the gas turbine engine via a first manifold and a second manifold during a first mode of operation; stopping fuel supply to the combustor via the second manifold and continuing to supply fuel to the combustor via the first manifold during a second mode of operation; and, after stopping fuel supply to the combustor via the second manifold, purging fuel from the second manifold using a pressure inside the combustor to drive the fuel in the second manifold away from the combustor.

Abstract: There is disclosed a double skin combustor for a gas turbine engine. The combustor has a radially inner liner and a radially outer liner defining therebetween an annular combustion chamber. The radially inner liner and the radially outer liners both have a hot skin and a cold skin defining a cooling cavity therebetween. The cold skin has a plurality of segments joined to one another by sliding joints. The cooling cavity between the hot skin and the cold skin may be compartmentalized into individual cavities between the sliding joints.

Abstract: A gas turbine engine combustor has a shell defining a combustion chamber having a primary zone and a dilution zone downstream of the primary zone. The shell has an outer skin and an inner skin defining an air gap therebetween. The inner skin in the upstream portion of the primary zone is free from effusion holes and has heat transfer augmenters projecting from a back side thereof into the air gap. Effusion holes in the inner skin are only disposed downstream towards the tail end of the primary zone in order to delay the injection of any disruptive cooling air that could potentially interfere with the combustion process.

Abstract: There is disclosed a double skin combustor for a gas turbine engine. The combustor has a radially inner liner and a radially outer liner defining therebetween an annular combustion chamber. The radially inner liner and the radially outer liners both have a hot skin and a cold skin defining a cooling cavity therebetween. The cold skin has a plurality of segments joined to one another by sliding joints. The cooling cavity between the hot skin and the cold skin may be compartmentalized into individual cavities between the sliding joints.

Abstract: A gas turbine engine combustor has a shell defining a combustion chamber having a primary zone and a dilution zone downstream of the primary zone. The shell has an outer skin and an inner skin defining an air gap therebetween. The inner skin in the upstream portion of the primary zone is free from effusion holes and has heat transfer augmenters projecting from a back side thereof into the air gap. Effusion holes in the inner skin are only disposed downstream towards the tail end of the primary zone in order to delay the injection of any disruptive cooling air that could potentially interfere with the combustion process.

Abstract: A combustor with a liner where each of the walls has a respective circumferential row of dilution holes defined therethrough adjacent a junction between the primary zone and the dilution zone. In the primary zone, the inner surface of each of the walls is covered by at least one heat shield attached thereto and spaced apart therefrom to allow air circulation between the inner surface and the at least one heat shield, the walls each having a plurality of cooling holes defined therethrough having a smaller diameter than that of the dilution holes. In the dilution zone, the inner surface of each of the walls is free of heat shields, and the walls each have a plurality of effusion cooling holes defined therethrough and having a smaller diameter than that of the dilution holes.

Abstract: A combustor with a liner where each of the walls has a respective circumferential row of dilution holes defined therethrough adjacent a junction between the primary zone and the dilution zone. In the primary zone, the inner surface of each of the walls is covered by at least one heat shield attached thereto and spaced apart therefrom to allow air circulation between the inner surface and the at least one heat shield, the walls each having a plurality of cooling holes defined therethrough having a smaller diameter than that of the dilution holes. In the dilution zone, the inner surface of each of the walls is free of heat shields, and the walls each have a plurality of effusion cooling holes defined therethrough and having a smaller diameter than that of the dilution holes.

Abstract: A heat shield unit for a gas turbine engine combustor comprises a panel body secured to a combustor liner. A first surface of the body is oriented toward a combustion zone of a combustor. A second surface is oriented toward the liner. The body is separated into upstream and downstream portions. Pin fins project from the second surface of the body. The pin fins are arranged in arrays of at least two different densities of volume of pin fins per unit volume. One density, lower than the second density, is in the upstream portion and another in the downstream portion of the body. Connectors connect the body to the liner with a line between the upstream and downstream portions of the body aligned with fluid-coolant injection apertures in the liner. A gas turbine engine combustor and a method for cooling a heat shield unit in a combustor liner of a gas turbine engine are also provided.

Abstract: A heat shield unit for a gas turbine engine combustor comprises a panel body secured to a combustor liner. A first surface of the body is oriented toward a combustion zone of a combustor. A second surface is oriented toward the liner. The body is separated into upstream and downstream portions. Pin fins project from the second surface of the body. The pin fins are arranged in arrays of at least two different densities of volume of pin fins per unit volume. One density, lower than the second density, is in the upstream portion and another in the downstream portion of the body. Connectors connect the body to the liner with a line between the upstream and downstream portions of the body aligned with fluid-coolant injection apertures in the liner. A gas turbine engine combustor and a method for cooling a heat shield unit in a combustor liner of a gas turbine engine are also provided.

Abstract: A fuel injection nozzle for a gas turbine engine has a central fuel ejection nozzle and a plurality of airflow passages within the spray tip that include a first and second group of circumferentially spaced apart fuel-spray forming airflow passages disposed on opposite sides of a transverse axis and oriented towards each other such as to produce opposed fuel spray shaping air jets which generate a shaped final fuel spray.

Abstract: A fuel injection nozzle for a gas turbine engine has a central fuel ejection nozzle and a plurality of airflow passages within the spray tip that include a first and second group of circumferentially spaced apart fuel-spray forming airflow passages disposed on opposite sides of a transverse axis and oriented towards each other such as to produce opposed fuel spray shaping air jets which generate a shaped final fuel spray.

Abstract: The support boss is used in a combustor of a gas turbine engine. It comprises a side wall defining an internal space. The side wall has at least one air inlet orifice. It also comprises a bottom wall closing one end of the internal space. The bottom wall has at least one air outlet orifice.