Acoustic structure with array of interconnected resonators, and anti-icing system

A gas turbine engine comprising:

• a fan delivering air into a bypass duct defined between a nacelle and an inner core housing, said inner core housing receiving a compressor section, a turbine section and a combustor;
• said nacelle having an inner periphery with a forwardmost point, and receiving an acoustic structure on the inner periphery adjacent the forwardmost point;
• and
• the acoustic structure being defined by a three dimensional array of interconnected resonators, with the interconnected resonators extending in a radial direction, a circumferential direction and an axial direction all defined about a rotational axis of the engine, with the interconnected resonators having a larger cross-sectional area central body, and six members connecting the larger cross-sectional area of the resonators to adjacent resonators at respective larger cross-sectional area;
• a perforated face sheet inward of the three dimensional array of interconnected resonator;
• and
• an anti-icing system;
• an opening through the larger cross-sectional area and at least some of the tube portions adjacent the larger cross-sectional area, and there being openings formed between adjacent ones of the interconnected resonators and extending in the circumferential, radial and axial directions;
• a radio frequency absorber provided by the three dimensional array, and a radio frequency radiator;
• and
• wherein the radio frequency absorber is capable to convert more than 50% of received radio frequency energy from the radio frequency radiator into heat across a range of 1-100 Gigahertz.