Bearfoil
Machinbird
Why have an inlet at all? A diaphragm of flexible material covering a void at some set Pressure. The deflection of the 'Tympanum' is the a/s. In another application, perhaps a "particle separator"? Very important (expensive) Helicopter kit. At these temps, it really isn't ice, it is more like "sand"?
Bearfoil, not a bad question at all.
The tympanum (diaphragm) concept has some limitations but could work under limited conditions.
Limiting factors would be surface icing and any significant angle of attack-Alpha or Beta.
The void behind the membrane would likely be liquid filled to transmit pressure directly to the transducer. The liquid would have to remain liquid under all flight conditions, and the thermal expansion characteristics would have to be moderate.
The shape of the membrane would have to be such that you had stagnation pressure over the entire surface area.
The system would not work well at significant angles relative to the airflow since the stagnation point would not stay put.
Finally rupture of the membrane or other system leakage would unsupport the membrane and would cause system error. Use of a gas behind the membrane would not work because of PV=RT.
A better approach would likely be a small diaphragm with built in strain gages mounted on some sort of projection that gets it out of the aircraft's boundary layer. In essence moving the transducer out to the surface of the aircraft.
Dust separator concepts would take away from the stagnation pressure. You would probably want something in front of the transducer diaphragm that resembled current pitot tube openings to ensure capture of actual stagnation pressure-but that leads us circularly back to the present design, heating, drain holes and all, with the transducer closer to the scene of action.
