Aero-acoustically dampened bleed valve

A turbine engine comprising:

• a first compressor;
• a second compressor;
• a bleed port including an inlet and an outlet;
• a variable bleed valve (VBV) door positioned adjacent the outlet of the bleed port, the VBV door mechanically coupled to the bleed port to actuate a variable bleed apparatus;
• a first porous facesheet positioned across the inlet of the bleed port;
• and
• a second porous facesheet positioned a first distance from the first porous facesheet, the second porous facesheet to be substantially parallel relative to the first porous facesheet, wherein a gap is formed between the first porous facesheet and the second porous facesheet, the gap between the first porous facesheet and the second porous facesheet tuned to a frequency of acoustic tones generated within the bleed port.

A variable bleed valve system for use in a turbine engine, the variable bleed valve system comprising:

• a bleed port extending from a casing of the turbine engine, the casing of the turbine engine defining a first flowpath for a fluid, an inner surface of the bleed port defining a second flowpath for at least a portion of the fluid;
• a resonant chamber coupled to an outer surface of the bleed port via a neck extending from a first wall of the bleed port and acoustically coupled to the resonant chamber and the bleed port, the neck defined by a second shape corresponding to a frequency of acoustic tones generated within the bleed port;
• a first porous facesheet coupled to an inlet of the bleed port, the first porous facesheet to extend across the inlet of the bleed port;
• and
• a second porous facesheet positioned a first distance from the first porous facesheet, the second porous facesheet to be substantially parallel relative to the first porous facesheet, wherein a gap is formed between the first porous facesheet and the second porous facesheet, the gap between the first porous facesheet and the second porous facesheet tuned to a frequency of acoustic tones generated within the bleed port.