System for diffusing bleed air flow

An apparatus configured to diffuse a flow of bleed air drawn from upstream of a combustion chamber of a gas turbine engine, comprising:

• a diffuser having:
• an inlet collar configured to receive the flow of bleed air in a direction substantially along a longitudinal axis of the diffuser;
• an end wall longitudinally spaced from the inlet collar and configured to block the flow of bleed air in a direction substantially along the longitudinal axis;
• a first diffuser wall and a second diffuser wall spaced concentrically relative to each other, each of the first and second diffuser being positioned between the inlet collar and the end wall and including a plurality of perforations configured to permit the flow of bleed air to exit the apparatus at an angle relative to the longitudinal axis;
• and
• a third diffuser wall spaced concentrically relative to the first and second diffuser walls;
• and
• an exhaust collector box configured to receive a flow of exhaust from a gas turbine engine and receive the flow of bleed air from the diffuser,
• wherein the diffuser is disposed at least partially within the exhaust collector box.

A gas turbine engine comprising:

• a bleed air pipe;
• a combustion section, including:
• a combustion liner enclosing a combustion chamber;
• a fuel inlet configured to supply fuel to the combustion chamber;
• and
• a bleed air inlet passage, the bleed inlet passage configured to direct a flow of bleed air from the combustion section to the bleed air pipe;
• a bleed air valve, the bleed air valve attached to the bleed air pipe and configured to regulate the flow of bleed air therethrough;
• an inlet collar configured to receive the flow of bleed air from the bleed air pipe in a direction substantially along a longitudinal axis of the diffuser;
• an end wall longitudinally spaced from the inlet collar and configured to block the flow of bleed air in a direction substantially along the longitudinal axis;
• a first diffuser wall spaced concentrically relative to a second diffuser wall, each of the first and second diffuser walls encircling the longitudinal axis, being positioned between the inlet collar and the end wall, and including a plurality of perforations configured to permit the flow of bleed air to exit the apparatus at an angle relative to the longitudinal axis;
• and
• a third diffuser wall spaced concentrically relative to the first and second diffuser walls.