Interactions modelling for a tiltrotor in host: Application to the ERICA concept

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1 _{Helicopter Overall Simulation Tool.}

2 _{Enhanced Rotorcraft Innovative Concept Achievement.} Back to Session Subjects

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Figure 1: ERICA wing at 0 and 90° tilt wing angle.

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Figure 2: Wing download evolution with the tilt wing angle in hover

Figure 3: Total power evolution with the tilt wing angle in hover. ), " $ " , 2 + + , $ " 2 " +, " , , ( A1 /IH @B 2 4 " +$ A1 /I E@ 1 /I @B# +$ E* , 2 , , 2 + + 4 9 ( ( + + , ( 2 C$ # ) , 4 , 2 + + , , ( 2 C$ * , ( * 2 + , 4 &( # * " , " , , + AH @* E@ @B $ , 4 ( " , ( $ 2 + + "" " & " 2 4 A" +$ DB* + + , ( 2 C$ # ), 2 + + 2 "$ " , " 2 ( , " , + 4 $ , , , ( A "# B# ), +9 , $ ( , " , 2 + , ( * , , 2 " , ( 2 C$ , $ # +$ E* , 2 , , " , , + , 4 # ), $ + 4 $ " , 2 + + ( " +$ D ( 2 , , 4 $ ( 4 $ 9 ($ # ), +9 " + , 2 + , ( , , , $ ( $ 2 2 6 "" " 4 " +, $ , #

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Figure 4: Optimum value of the tilt-wing angle for minimisation of total power requirement compared to the slipstream Tilt-wing angle law

Figure 6: Influence of forward speed and tilt-wing angle on total power requirement (DNAC=75°)

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Figure 8: Time simulation results including rotor/wing interaction, for an acceleration from hover up to 120km/h at a constant altitude in helicopter mode

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Figure 9: Schematic representation of the rotors wake and its impact on the wing in helicopter mode for a lateral flight

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Figure 10: Influence of rotor wing interaction in helicopter mode for a sweep in lateral velocity (Roll moments are referenced to the centre line of the wing)

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Figure 11: Swirl Induced in the rotor wake

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Figure 12: Axial induced velocity at a location 0.1 R below rotor.

Figure 13: Swirl induced velocity at a location 0.1 R below rotor.

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Figure 14: Influence of the swirl and the direction of rotation on the wing download in hover.

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Figure 15: Flow model for momentum theory analysis of a rotor in forward flight.

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Figure 16: Ground effect on Mean Induced velocities.

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Figure 17: Flow model for rotor outwash analysis in ground effect.

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Figure 18: Comparison of peak outwash velocity in ground effect.

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Figure 20: Schematic ground fountain effect modelling with impinging jets.

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Figure 21: 2-jet fountain spreading characteristics (Ref. 19)

Figure 22: Empirical 2-jet fountain dynamic Pressure Profile (Ref. 19)

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