Combined acoustic and anti-ice engine inlet liner

In an air vehicle having a turbo engine including an inlet which receives intake airflow and is defined by an inner surface and a D-nose of the engine, an inlet liner for improved acoustic, anti-ice and drag performance comprising:

• a permeable acoustic layer defining the D-nose and formed to attenuate sound;
• and
• a pressurized fluid injecting device, in fluid communication with the acoustic layer, formed to inject fluid through the acoustic layer at the D-nose to reduce drag of the intake airflow and at a temperature sufficient to perform an anti-ice function thereat, the pressurized fluid injecting device comprises:
• a plenum in fluid communication with the acoustic layer;
• and
• a piccolo tube disposed adjacent the D-nose, the piccolo tube having a plurality of holes for injecting fluid therethrough into the plenum, being generally ring shaped and annularly disposed within the inlet.

In an air vehicle having a turbo engine including an inlet which receives intake airflow and is defined by an inner surface and a D-nose of the engine, an inlet liner for improved acoustic, anti-ice and drag performance comprising:

• a permeable acoustic layer defining the D-nose and formed to attenuate sound;
• and
• a pressurized fluid injecting device, in fluid communication with the acoustic layer, formed to inject fluid through the acoustic layer at the D-nose to reduce drag of the intake airflow and at a temperature sufficient to perform an anti-ice function thereat, the pressurized fluid injecting device comprises:
• a plenum in fluid communication with the acoustic layer;
• and
• a swirl tube disposed generally parallel to the intake airflow, having a plurality of holes for injecting fluid therethrough into the plenum such that the injected fluid circulates circumferentially about the acoustic layer within the plenum.

In an air vehicle, a turbo engine which receives intake airflow for improved acoustic, anti-ice and drag performance comprising:

• a D-nose;
• an inner surface adjacent the D-nose;
• a permeable acoustic layer defining the D-nose and the inner surface, the acoustic layer comprising:
• a frontface skin formed to allow fluid to pass therethrough;
• a backface skin formed to allow fluid to pass therethrough;
• and
• an acoustic core disposed between and in fluid communication with the frontface skin and the backface skin, formed to allow pressurized, heated fluid to pass therethrough and to attenuate sound;
• and
• a pressurized fluid injecting device in fluid communication with the acoustic layer, formed to inject fluid through the permeable acoustic layer at the D-nose to reduce drag of the intake airflow and at a temperature sufficient to perform an anti-ice function thereat, formed to inject fluid through the acoustic layer at the inner surface to reduce drag of the intake airflow.

In an air vehicle having a turbo engine including an inlet which receives intake airflow and is defined by an inner surface and a D-nose of the engine, a method of forming an inlet liner for improved acoustic, anti-ice and drag performance comprising the following steps:

• (a) forming a permeable acoustic layer formed to attenuate sound and defining the D-nose and the inner surface adjacent to the D-nose, the acoustic layer being formed by the following steps:
• (i) forming a frontface skin formed to allow fluid to pass therethrough;
• (ii) forming a backface skin formed to allow fluid to pass therethrough;
• and
• (iii) forming an acoustic core disposed between and in fluid communication with the frontface skin and the backface skin, formed to allow pressurized, heated fluid to pass therethrough and to attenuate sound;
• (b) injecting a pressurized fluid adjacent the acoustic layer at the D-nose to reduce drag of the intake airflow and at a temperature sufficient to perform an anti-ice function thereat;
• and
• (c) injecting a pressurized fluid adjacent the acoustic layer at the inner surface to reduce drag of the intake airflow.