Brush seal with cross-flow backing plate and thermal gradient reduction method

A method of providing a cooling flow to a ceramic matrix composite (CMC) component of a turbine engine through a brush seal, the CMC component having a hot side configured for exposure to a hot gas path of the turbine engine and an opposing cold side, the method comprising:

• providing at least one cavity in the CMC component, the at least one cavity having an entrance disposed on the cold side for receiving the cooling flow;
• disposing the brush seal adjacent the at least one cavity and the cold side of the CMC component to provide a radial face seal across the cavity of the CMC component with an inner diameter (ID) backing plate of the brush seal;
• passing the cooling flow from a source through a hole extending through the brush seal to provide the cooling flow to the at least one cavity of the CMC component;
• and
• passing leakage air that leaks through bristles of the brush seal to a cross-flow channel disposed on an inner surface of the ID backing plate, the cross-flow channel extending from an edge of the ID backing plate to the hole.

A cooling flow arrangement for a ceramic matrix composite (CMC) component of a turbine engine, the CMC component having a hot side configured for exposure to a hot gas path of the turbine engine and an opposing cold side, comprising:

• a cavity formed in the CMC component, the cavity having an entrance disposed on the cold side configured for receiving a cooling flow;
• a brush seal disposed adjacent the cavity and the cold side of the CMC component and configured to provide a radial face seal across the cavity of the CMC component, the brush seal further comprising a plurality of brush seal bristles configured to form a first seal against the CMC component;
• a hole extending through the central portion of the brush seal and positioned to provide the cooling flow to the cavity of the CMC component;
• and
• a cross-flow channel disposed on an inner surface of the brush seal to cross the radial face seal and extend to the hole.