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A computer-aided method suitable for assisting in the design of an aircraft by providing a variable distribution V over an aircraft surface inside a predefined parameter space by means of a reconstruction of the results obtained through computations for an initial group of points in the parameter sp

A computer-aided method suitable for assisting in the design of an aircraft by providing a variable distribution V over an aircraft surface inside a predefined parameter space by means of a reconstruction of the results obtained through computations for an initial group of points in the parameter space using a CFD model comprising in each of said computations the following steps: a) Selecting relevant shock wave structures being defined by its thickness δsw, its position Sswand the variable jump ΔV; b) Decomposing said variable distribution V into a smooth variable distribution Vsmooth and a shock wave variable distribution Vjump corresponding to said relevant shock wave structures; c) Obtaining the variable distribution V at any point of the parameter space as a reconstruction of the smooth variable distribution Vsmooth and the shock wave variable distribution Vjump obtained for said point.

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1. A computer-aided method suitable for assisting in the design or analysis of an aircraft by providing a variable distribution V over the three dimensional surface of an aircraft or an aircraft component inside a predefined parameter space by means of a reconstruction of the results obtained throug

1. A computer-aided method suitable for assisting in the design or analysis of an aircraft by providing a variable distribution V over the three dimensional surface of an aircraft or an aircraft component inside a predefined parameter space by means of a reconstruction of the results obtained through computations for an initial group of points in the parameter space using a CFD model in connection with a structured mesh defined on said three dimensional surface, characterized in that in each of said computations it comprises the following steps: a) Selecting at least one shock wave structure along a mesh line in the chord direction said shock wave structure extending between a first point and a last point in the mesh line, said shock wave being defined by its thickness δsw, its position ssw in the mid point between said first point and said last point and the variable jump ΔV between the last and the first point;b) Decomposing said variable distribution V obtained through computations for an initial group of points into a smooth variable distribution Vsmooth componentb). . . and a shock wave variable distribution Vjump component corresponding to said at least one shock wave structure;c) Obtaining the variable distribution V at a point of the parameter space other than one included in said initial group of points by combination of the smooth variable distribution Vsmooth component and the shock wave variable distribution Vjump obtained for said point from the values obtained in step b). 2. The computer-aided method according to claim 1, characterized in that said step a) comprises the following sub-steps: a1) seeking the maximum value of dV/ds along said mesh line, s being the arc length measured from the leading edge of the aerodynamic surface and finding that it is larger than a first predetermined value P1;a2) setting the amplitude of the shock wave as a thickness value around the mesh corresponding to the maximum value of dV/ds where dV/ds is larger than a second predetermined value P2 plus two additional points at each side of maximum dV/ds;a3) considering said shock wave if the variable jump ΔV is greater than a third predetermined value P3. 3. The computer-aided method according to claim 1, characterized in that when only one shock wave is taken into account it is split into two shock waves with the same position ssw, and thickness δsw and with the variable jump ΔV equal to half the total value. 4. The computer-aided method according to claim 1, characterized in that the shape of the shock wave variable distribution Vjump is a linear shape. 5. The computer-aided method according to claim 1, characterized in that the shape of the shock wave variable distribution Vjump is a non-linear shape. 6. The computer-aided method according to claim 1, characterized in that said variable distribution V is one or a combination of the following: the pressure distribution, the velocity components distribution, the mach number (euler computation) distribution, the friction components distribution, the temperature distribution, the density distribution, the energy distribution, the entropy distribution, the enthalpy distribution. 7. The computer-aided method according to claim 1, characterized in that said predefined parameter space includes one or more of the following parameters: angle of attack, Mach number, sideslip angle, wing aileron deflection angle, spoilers deflection, high lift devices deflection, canard deflection, landing gear deflected status, landing gear doors angle, APU inlet open angle, the vertical tailplane rudder deflection angle, the horizontal tailplane elevator angle, the horizontal tailplane setting angle. 8. The computer-aided method according to claim 1, characterized in that said aircraft component is one of the following: a wing, an horizontal tailplane, a vertical tailplane, fuselage, a high lift device, a spoiler, an engine, a canard.