Sections for shrouded propeller blade

Claim 2

Section for shrouded propeller blade, of which the relative thickness with respect to the chord is included between 9% and 15%, wherein, the curvature of said section having a maximum value at the leading edge thereof included between 47 and 98 as a function of said relative thickness, the upper surface line of said section comprises, from the leading edge to the trailing edge, three successive portions, such that in the first portion, the curvature decreases rapidly from said maximum value at the leading edge to a value close to 20 at a first point of which the reduced abscissa along the chord of the section, counted from the leading edge, is close to 1%; in the second portion, the curvature decreases more slowly from said value close to 20 at said first point up to a value close to 1 at a second point, of which the reduced abscissa along said chord, counted from the leading edge, is close to 25%; and in the third portion, the curvature is less than 1 between said second point and said trailing edge, whilst the lower surface line of said section comprises, from the leading edge to the trailing edge, three successive portions, such that in the first portion, the curvature decreases from said maximum value at the leading edge to a value close to 11 at a third point of which the reduced abscissa along the chord of the section, counted from said leading edge, is close to 2%; in the second portion, which extends from said third point up to a fourth point of which the reduced abscissa along the chord of the section, counted from said leading edge, is included between 30 and 70%, the curvature continues to decrease from this value close to 11 until it is cancelled; and in the third portion, the curvature is negative and less than 1 in absolute value, up to the trailing edge.

Claim 3

The section of claim 1, wherein the value COA of the curvature at the leading edge, with respect to the length 1 of the chord of the section, is given by the expression (1) COA=a1(e/1)+a2(e/1).sup.2 +a3(e/1).sup.3 +a4(e/1).sup.4 +a5(e/1).sup.5 in which e/1 is the maximum relative thickness of the section, and a1, a2, a3, a4 and a5 are constant coefficients.

Claim 4

The section of claim 2, wherein said constant coefficients have the following respective values: a1=-0.2936.10 6 a2=+0.99839.10 7 a3=-0.12551.10 9 a4=+0.69412.10 9 a5=-0.14276.10 10

Claim 5

The section of claim 1, wherein, along said second portion of upper surface, the curvature (CO) is given by the expression (2) CO.sup.1/2 =a6+a7(X/1).sup.1/2 +a8(X/1), in which a6, a7 and a8 are constant coefficients, X/1 being the reduced abscissa along the chord of the section, counted from the leading edge, of any point of this second portion.

Claim 6

The section of claim 4, wherein said constant coefficients have the following respective values: a6=+0.72957.10 a7=-0.31509.10 2 a8=+0.37217.10 2

Claim 7

The section of claim 1 and of which the coefficient of lift of adaptation is less than 0.3, wherein said third portion of upper surface comprises a point of inversion of curvature, of which the reduced abscissa along the chord of the section, counted from the leading edge, is included between 45% and 85%.

Claim 8

The section of claim 6, wherein the reduced abscissa of said point of inversion of curvature, along the chord of said section and counted from the leading edge, is given by the expression (3) XE/1=0.58333+0.91667Cza-1.1667(Cza) 2 in which Cza is the value of the coefficient of lift of adaptation.

Claim 9

The section of claim 1, wherein the reduced abscissa of the point of zero curvature of said second portion of upper surface is given by the formula (4) X/1=a9(e/1)+a10(e/1).sup.2 +a11(e/1).sup.3 a12(e/1).sup.4 +a13 (e/1).sup.5 in which e/1 is the maximum relative thickness of the section (1) and a9, a10, a11, a12 and a13 are constant coefficients.

Claim 10

The section of claim 8, wherein said constant coefficients present the following respective values: a9=-0.39176.10 3 a10=+0.13407.10 5 a11=-0.16845.10 6 a12=+0.92807.10 6 a13=-0.18878.10 7

Claim 11

The section of claim 1, defined in known manner from a law of variation of thickness and from a median line, wherein, as a function of the reduced abscissa X/1 along the chord counted from the leading edge, the reduced ordinates Y/1 and Ye/1 of said median line and of said thickness are respectively given by the following formulae: (5) Y/1=c1(X/1)+c2(X/1).sup.2 +c3(X/1).sup.3 +c4(X/1).sup.4 +c5(X/1).sup.5 +c6(X/1).sup.6 +c7(X/1).sup.7 (6) Ye/1=b1(X/1)+b2(X/1).sup.2 +b3(X/1).sup.3 +b4(X/1).sup.4 +b5(X/1).sup.5 +b6(X/1).sup.6 +b7(X/1).sup.7 +b8(X/1).sup.8 +b9(X/1).sup.9 +b10(X/1).sup.10 in which the different coefficients b1 to b10 and c1 to c7 are constant.

Claim 12

The section of claim 10, wherein the different constant coefficients b1 to b10 are given by the formulae hereinafter: (7.1) b1=b11(e/1)+b12(e/1).sup.2 +b13(e/1).sup.3 +b14(e/1).sup.4 +b15(e/1).sup.5 +b16(e/1).sup.6 (7.2) b2=b21(e/1)+b22(e/1).sup.2 +b23(e/1).sup.3 +b24(e/1).sup.4 +b25(e/1).sup.5 +b26(e/1).sup.6 (7.10) b10=b101(e/1)+b102(e/1).sup.2 +b103(e/1).sup.3 +b104(e/1).sup.4 +b105(e/1).sup.5 +b106(e/1).sup.6 in which e/1 is the maximum reduced thickness of said section and b11 to 106 are constant coefficients.

Claim 13

The section of claim 11, wherein the constant coefficients b11 to b106 have the following respective values: ______________________________________ b11 =+0,98542.10.sup.5 b61 = -0,18709.10.sup.10 b12 = -0,43028.10.sup.7 b62 = +0,82093.10.sup.11 b13 = +0,74825.10.sup.8 b63 = -0,14340.10.sup.13 b14 = -0,64769.10.sup.9 b64 = +0,12464.10.sup.14 b15 = +0,27908.10.sup.10 b65 = -0,53912.10.sup.14 b16 = -0,47889.10.sup.10 b66 = +0,92831.10.sup.14 b21 = -0,33352.10.sup.7 b71 = +0,25348.10.sup.10 b22 = +0,14610.10.sup.9 b72 = -0,11123.10.sup.12 b23 = -0,25480.10.sup.10 b73 = +0,19432.10.sup.13 b24 = +0,22115.10.sup.11 b74 = -0,16892.10.sup.14 b25 = -0,95525.10.sup.11 b75 = +0,73066.10.sup.14 b26 = +0,16428.10.sup.12 b76 = -0,12582.10.sup.15 b31 = +0,39832.10.sup.8 b81 = -0,20869.10.sup.10 b32 = -0,17465.10.sup.10 b82 = +0,91583.10.sup.11 b33 = +0,30488.10.sup.11 b83 = -0,16000.10.sup.13 b34 = -0,26484.10.sup.12 b84 = -0,13909.10.sup.14 b35 = + 0,11449.10.sup.13 b85 = -0,60166.10.sup.14 b36 = -0,19704.10.sup.13 b86 = +0,10361.10.sup.15 b41 = -0,24305.10.sup.9 b91 = +0,95554.10.sup.9 b42 = +0,10661.10.sup.11 b92 = -0,41936.10.sup.11 b43 = -0,18618.10.sup.12 b93 = +0,73266.10.sup.12 b44 = +0,16178.10.sup.13 b94 = -0,63693.10.sup.13 b45 = -0,69957.10.sup.13 b95 = +0,27553.10.sup.14 b46 = +0,12043.10.sup.14 b96 = -0,47450.10.sup.14 b51 = +0,86049.10.sup.9 b101 = -0,18663.10.sup.9 b52 = -0,37753.10.sup.11 b102 = +0,81909.10.sup.10 b53 = +0,65939.10.sup.12 b103 = -0,14311.10.sup.12 b54 = -0,57309.10.sup.13 b104 = +0,12441.10.sup.13 b55 = +0,24785.10.sup.14 b105 = -0,58321.10.sup.13 b56 = -0,42674.10.sup.14 b106 = +0,92688.10.sup.13 ______________________________________

Claim 14

The section of claim 10, of which the median line presents a maximum relative curvature of between - 2% and +5%, wherein the different constant coefficients c1 to c7 are given by the following formulae: (8.1) c1=c11(e/1)+c12(e/1).sup.2 +c13(e/1).sup.3 +c14(e/1).sup.4 +c15(e/1).sup.5 +c16(e/1).sup.6 (8.2) c2=c21(e/1)+c22(e/1).sup.2 +c23(e/1).sup.3 +c24(e/1).sup.4 +c25(e/1).sup.5 +c26(e/1).sup.6 (8.7) c7=c71(e/1)+c72(e/1).sup.2 +c73(e/1).sup.3 +c74(e/1).sup.4 +c75(e/1).sup.5 +c76(e/1).sup.6 in which e/1 is the maximum reduced thickness of said section and c11 to c76 are constant coefficients.

Claim 15

The section of claim 13, wherein the constant coefficients c11 to c76 have the following values: ______________________________________ c11 =-0,29874.10.sup.1 c51 = -0,18750.10.sup.4 c12 = -0,61332.10.sup.2 c52 = +0,72410.10.sup.5 c13 = +0,60890.10.sup.5 c53 = +0,90745.10.sup.7 c14 = -0,43208.10.sup.6 c54 = -0,54687.10.sup.9 c15 = -0,12037.10.sup.9 c55 = +0,58423.10.sup.10 c16 = +0,24680.10.sup.10 c56 = +0,50242.10.sup.11 c21 = +0,17666.10.sup.2 c61 = +0,12366.10.sup.4 c22 = +0,70530.10.sup.4 c62 = -0,43178.10.sup.5 c23 = -0,40637.10.sup.6 c63 = -0,61307.10.sup.7 c24 = -0,28310.10.sup.8 c64 = +0,33946.10.sup.9 c25 = +0,20813.10.sup.10 c65 = -0,26651.10.sup.10 c26 = -0,31463.10.sup.11 c66 = -0,49209.10.sup.11 c31 = -0,38189.10.sup.3 c71 = -0,31247.10.sup.3 c32 = +0,31787.10.sup.2 c72 = +0,83939.10.sup.4 c33 = +0,23684.10.sup.7 c73 = +0,16280.10.sup.7 c34 = -0,47636.10.sup.8 c74 = -0,74431.10.sup.8 c35 = - 0,26705.10.sup.10 c75 = +0,30520.10.sup.8 c36 = +0,65378.10.sup.11 c76 = +0,21265.10.sup.11 c41 = +0,13180.10.sup.4 c42 = -0,44650.10.sup.5 c43 = -0,65945.10.sup.7 c44 = +0,35822.10.sup.9 c45 = -0,24986.10.sup.10 c46 = -0,58675.10.sup.11 ______________________________________

Claim 16

The section of claim 10, wherein the maximum relative camber Kmax of the median line of a section is determined, as a function of the value of the coefficient of lift of adaptation Cza, by the following formula: (9) Kmax=d1(Cza)+d2(Cza).sup.2 +d3(Cza).sup.3 +d4(Cza).sup.4 +d5(Cza).sup.5 +d6(Cza).sup.6 in which d1 to d6 are constant coefficients.

Claim 17

The section of claim 15, wherein the constant coefficients d1 to d6 have the following values: d1=+0.11017 d2=-0.30167 d3=-0.58541 d4=+0.39240.10 d5=-0.53223.10 d6=+0.22132.10

Claim 18

The section of claim 1, having a maximum relative thickness equal to 9.5% and for a coefficient of lift of adaptation equal to 1, wherein, as a function of the reduced abscissa X/1 along the chord, counted from the leading edge, the reduced ordinates of its line of upper surface are given between X/1=0 and X/1=0.39433, by the formula (10) Y/1=f1(X/1).sup.1/2 +f2(X/1)+f3(X/1).sup.2 +f4(X/1).sup.3 +f5(X/1).sup.4 +f6(X/1).sup.5 +f7(X/1).sup.6 with f1=+0.16227 f2=-0.11704.10 -1 f3=+0.13247 f4=-0.25016.10 f5=+0.10682.10 2 f6=-0.22210.10 2 f7=+0.17726.10 2 between X/1=0.39433 and X/1=1, by the formula (11) Y/1=g0+g1(X/1)+g2(X/1).sup.2 +g3(X/1).sup.3 +g4(X/l).sup.4 +g5(X/1).sup.5 +g6(X/1).sup.6 with g0=+0.22968 g1=+0.17403.10 g2=+0.77952.10 g3=-0.17457.10 2 g4=+0.20845.10 2 g5=-0.13004.10 2 g6=+0.33371.10 whilst the reduced ordinates of the line of lower surface of said section are given between X/1=0 and X/1=0.11862, by the formula (12) Y/1=h1(X/1).sup.1/2 +h2(X/1)+h3(X/1).sup.2 +h4(X/1).sup.3 +h5(X/1).sup.4 +h6(X/1).sup.5 +h7(X/1).sup.6 with h1=-0.13971 h2=+0.10480.10 -3 h3=+0.51698.10 h4=-0.11297.10 3 h5=+0.14695.10 4 h6=-0.96403.10 4 h7=+0.24769.10 5 between X/1=0.11862 and X/1=1, by the formula (13) Y/1=i0+i1(X/1)+i2(X/1).sup.2 +i3(X/1).sup.3 +i4(X/1).sup.4 +i5(X/1).sup.5 +i6(X/1).sup.6 with i0=-0.25915.10 -1 i1=-0.96597.10 -1 i2=+0.49503 i3=+0.60418.10 -1 i4=-0.17206.10 i5=+0.20619.10 i6=-0.77922

Claim 19

The section of claim 1, having a maximum relative thickness equal to 10.2% and for a coefficient of lift of adaptation equal to 0.9, wherein, as a function of the reduced abscissa X/1 along the chord, counted from the leading edge, the reduced ordinates of the line of upper surface are given between X/1=0 and X/1=0.39503, by the formula (14) Y/1=j1(X/1).sup.1/2 +j2(X/1)+j3(X/1).sup.2 +j4(X/1).sup.3 +j5(X/1).sup.4 +j6(X/1).sup.5 +j7(X/1).sup.6 with j1=+0.14683 j2=-0.67115.10 -2 j3=+0.44720 j4=-0.36828.10 j5=+0.12651.10 2 j6=-0.23835.10 2 j7=+0.18155.10 2 between X/1=0.39503 and X/1=1, by the formula (15) Y/1=k0+k1(X/1)+k2(X/1).sup.2 +k3(X/1).sup.3 +k4(X/1).sup.4 +k5(X/1).sup.5 +k6(X/1).sup.6 with k0=+0.45955 k1=-0.39834.10 k2=+0.16726.10 2 k3=-0.35737.10 2 k4=+0.41088.10 2 k5=-0.24557.10 2 k6=+0.60088.10 whilst the reduced ordinates of the line of lower surface of said section are given between X/1=0 and X/1=0.14473, by the formula (16) Y/1=m1(X/1).sup.178 +m2(X/1)+m3(X/1).sup.2 +m4(X/1).sup.3 +m5(X/1).sup.4 +m6(X/1).sup.5 +m7(X/1).sup.6 with m1=-0.13297 m2=+0.36163.10 -1 m3=+0.17284.10 m4=-0.27664.10 2 m5=+0.30633.10 3 m6=31 0.16978.10 4 m7=+0.36477.10 4 between X/1=0.14473 and X/1=1, by the formula (17) Y/1=n0+n1(X/ 1)+n2(X/1).sup.2 +n3(X/1).sup.3 +n4(X/1).sup.4 +n5(Xf).sup.5 +n6(X/1).sup.6 with n0=-0.30824.10 -1 n1=-0.20564.10 -1 n2=-0.21738 n3=+0.24105.10 n4=-0.53752.10 n5=+0.48110.10 n6=-0.15826.10

Claim 20

The section of claim 1, having a maximum relative thickness equal to 11.7% and for a coefficient of lift of adaptation equal to 0.5, wherein, as a function of the reduced abscissa X/1 along the chord, counted from the leading edge, the reduced ordinates of the line of upper surface are given between X/1=0 and X/1=0.28515, by the formula (18) Y/1=t1(X/1).sup.1/2 +t2(X/1)+t3(X/1).sup.2 +t4(X/1).sup.3 +t5(X/1).sup.4 +t6(X/1).sup.5 +t7(X/1).sup.6 with t1=+0.21599 t2=-0.17294 t3=+0.22044.10 t4=-0.26595.10 2 t5=+0.14642.10 3 t6=-0.39764.10 3 t7=+0.42259.10 3 between X/1=0.28515 and X/1=1, by the formula (19) Y/1=u0+u1(X/1)+u2(X/1).sup.2 +u3(X/1).sup.3 +u4(X/1).sup.4 +u5(X/1).sup.5 +u6(X/1).sup.6 with u0=+0.39521.10 -1 u1=+0.26170 u2=-0.47274 u3=-0.40872 u4=+0.15968.10 u5=-0.15222.10 u6=+0.51057 whilst the reduced ordinated of the line of lower surface of said section are given between X/1=0 and X/1=0.17428, by the formula (20) Y/1=v1(X/1).sup.1/2 +v2(X/1)+v3(X/1).sup.2 +v4(X/1).sup.3 +v5(X/1).sup.4 +v6(X/1).sup.5 +v7(X/1).sup.6 with v1=-0.16526 v2=-0.31162.10 -1 v3=+0.57567.10 v4=-0.10148.10 3 v5=+0.95843.10 3 v6=-0.44161.10 4 v7=+0.78519.10 4 between X/1=0.17428 and X/1=1, by the formula (21) Y/1=w0+w1(X/1)+W2(X/1).sup.2 +w3(X/1).sup.3 +w4(X/1).sup.4 +w5(X/1).sup.5 +w6(W/1).sup.6 with w0=-0.25152.10 -1 w1=-0.22525 w2=+0.89038 w3=-0.10131.10 w4=+0.16240 w5=+0.46968 w6=-0.26400

Claim 21

The section of claim 1, having a maximum relative thickness equal to 12% and for a coefficient of lift of adaptation equal to 0.6 wherein, as a function of the reduced abscissa X/1 along the chord, counted from the leading edge, the reduced ordinates of the line of upper surface are given between X/1=0 and X/1=0.29461, by the formula (22) Y/1=p1(X/1).sup.178 +p2(X/1)+p3(X/1).sup.2 +p4(X/1).sup.3 +p5(X/1).sup.4 +p6(X/1).sup.5 +p7(X/1).sup.6 with p1=+0.16347 p2=+0.20845 p3=-0.20506.10 p4=+0.13223.10 2 p5=-0.63791.10 2 p6=+0.16200.10 3 p7=-0.16302.10 3 between X/1=0.29461 and X/1=1, by the formula (23) Y/1=q0+q1(X/1)+q2(X/1).sup.2 +q3(X/1).sup.3 +q4(X/1).sup.4 +q5(X/1).sup.5 +q6(X/1).sup.6 with q0=+0.54860.10 -1 q1=+0.13872 q2=+0.16460 q3=-0.17424.10 q4=+0.28085.10 q5=-0.19062.10 q6=+0.48442 whilst the reduced ordinates of the line of lower surface of said section are given between X/1=0 and X/1=0.14931, by the formula (24) Y/1=r1(X/1).sup.1/2 +r2(X/1)+r3(X/1).sup.2 +r4(X/1).sup.3 +r5(X/1).sup.4 +r6(X/1).sup.5 +r7(X/1).sup.6 with r1=-0.19086 r2=+0.29842 r3=-0.51359.10 r4=+0.11144.10 3 r5=-0.11385.10 4 r6=+0.56797.10 4 r7=-0.11091.10 5 between X/1=0.14931 and X/1=1, by the formula (25) Y/1=s0+s1(X/1)+s2(X/1).sup.2 +s3(X/1).sup.3 +s4(X/1).sup.4 +s5(X/1).sup.5 +s6(X/1).sup.6 with s0=-0.31248.10 -1 s1=-0.12350 s2=+0.42720 s3=+0.32923 s4=-0.19650.10 s5=+0.2109910 s6=-0.74935

Claim 22

The section of claim 1, having a maximum relative thickness equal to 12.8% and for a coefficient of lift of adaptation equal to 0.2, wherein, as a function of the reduced abscissa X/1 along the chord, counted from the leading edge, the reduced ordinates of the line of upper surface are given between X/1=0 and X/1=0.26861, by the formula (26) Y/1=α1(X/1).sup.1/2 +α2(X/1)+α3(X/1).sup.2 α4(X/1).sup.3 +α5(X/1).sup.4 +α6(X/1).sup.5 +α7(X/1).sup.6 with α1=+0.19762 α2=+0.17213 α3=-0.53137.10 α4=+0.56025.10 2 α5=-0.32319.10 3 α6=+0.92088.10 3 α7=-0.10229.10 4 between X/1=0.26861 and X/1=1, by the formula (27) Y/1=β0+β1(X/1)+β2(X/1).sup.2 +β3(X/1).sup.3 +β4(X/1).sup.4 +β5(X/1).sup.5 +β6(X/1).sup.6 with β0=+0.28900.10 -1 β1=+0.38869 β2=-0.10796.10 β3=+0.80848 β4=+0.45025

Claim 23

β=- 0. 10636.10 β6=+0.47182 whilst the reduced ordinates of the line of lower surface of said section are given between X/1=0 and X/1=0.20934, by the formula (28) Y/1=γ1(X/1).sup.1/2 +γ2(X/1)+γ3(X/1).sup.2 +γ4(X/1).sup.3 +γ5(X/1).sup.4 +γ6(X/1).sup.5 +γ7(X/1).sup.6 with γ1=-0.25376 γ2=+0.61860 γ3=-0.96212.10 γ4=+0.12843.10 3 γ5=-0.90701.10 3 γ6=+0.32291.10 4 γ7=-0.45418.10 4 between X/1=0.20934 and X/1=1, by the formula (29) Y/1=δ0+δ1(X/1)+δ2(X/1).sup.2 +δ3(X/1)+δ4(X/1).sup.4 +δ5(X/1).sup.5 +δ6(X/1).sup.6 with δ0=-0.25234.10 -1 δ1=-0.32905 δ2=+0.10890.10 δ3=-0.10066.10 δ4=-0.32520 δ5=+0.11325.10 δ6=-0.54043

Claim 24

β=- 0. 10636.10 β6=+0.47182 whilst the reduced ordinates of the line of lower surface of said section are given between X/1=0 and X/1=0.20934, by the formula (28) Y/1=γ1(X/1).sup.1/2 +γ2(X/1)+γ3(X/1).sup.2 +γ4(X/1).sup.3 +γ5(X/1).sup.4 +γ6(X/1).sup.5 +γ7(X/1).sup.6 with γ1=-0.25376 γ2=+0.61860 γ3=-0.96212.10 γ4=+0.12843.10 3 γ5=-0.90701.10 3 γ6=+0.32291.10 4 γ7=-0.45418.10 4 between X/1=0.20934 and X/1=1, by the formula (29) Y/1=δ0+δ1(X/1)+δ2(X/1).sup.2 +δ3(X/1)+δ4(X/1).sup.4 +δ5(X/1).sup.5 +δ6(X/1).sup.6 with δ0=-0.25234.10 -1 δ1=-0.32905 δ2=+0.10890.10 δ3=-0.10066.10 δ4=-0.32520 δ5=+0.11325.10 δ6=-0.54043

Claim 25

The section of claim 1, having a maximum relative thickness equal to 13.9% and for a coefficient of lift of adaptation equal to -0.1, wherein, as a function of the reduced abscissa X/1 along the chord, counted from the leading edge, the reduced ordinates of the line of upper surface are given between X/1=0 and X/1=0.19606, by the formula (30) Y/1=ε1(X/1).sup.1/2 +ε2(X/1)+ε3(X/1).sup.2 +ε4(X/1).sup.3 +ε5(X/1).sup.4 +ε6(X/1).sup.5 +ε7(X/1).sup.6 with ε1=+0.22917 ε2=-0.22972 ε3=+0.21262.10 ε4=-0.39557.10 2 ε5=+0.32628.10 3 ε6=-0.13077.10 4 ε7=+0.20370.10 4 between X/1=0.19606 and X/1=1, by the formula (31) Y/1=λ0+λ1(X/1)+λ2(X/1).sup.2 +λ3(X/1).sup.3 +80 4(X/1).sup.4 +λ5(X/1).sup.5 +λ6(X/1).sup.6 with λ0=+0.32500.10 -1 λ1=+0.29684 λ2=-0.99723 λ=+0.82973 λ4=+0.40616 λ5=-0.10053.10 λ6=+0.44222 whilst the reduced ordinates of the line of lower surface of said section are given between X/1=0 and X/1=0.26478, by the formula (32) Y/1=μ1(X/1).sup.178 +μ2(X/1)+μ3(X/1).sup.2 +μ4(X/1).sup.3 +μ5(X/1).sup.4 +μ6(X/1).sup.5 +μ7(X/1).sup.6 with μ1=-0.19314 μ2=-0.22031 μ3=+0.41399.10

Claim 26

μ=- 0. 41389.10 2 μ5=+0.23230.10 3 μ6=-0.66179.10 3 μ7=+0.74216.10 3 between X/1=0.26478 and X/1=1, by the formula (33) Y/1=ν0+ν1(X/1)+ν2(X/1).sup.2 +ν3(X/1).sup.3 +ν4(X/1).sup.4 +ν5(X/1).sup.5 +ν6(X/1).sup.6 with ν0=-0.42417.10 -1 ν1=-0.29161 ν2=+0.57883 ν3=+0.41309 ν4=-0.19045.10 ν5=+0.18776.10 ν6=-0.63583

Claim 27

μ=- 0. 41389.10 2 μ5=+0.23230.10 3 μ6=-0.66179.10 3 μ7=+0.74216.10 3 between X/1=0.26478 and X/1=1, by the formula (33) Y/1=ν0+ν1(X/1)+ν2(X/1).sup.2 +ν3(X/1).sup.3 +ν4(X/1).sup.4 +ν5(X/1).sup.5 +ν6(X/1).sup.6 with ν0=-0.42417.10 -1 ν1=-0.29161 ν2=+0.57883 ν3=+0.41309 ν4=-0.19045.10 ν5=+0.18776.10 ν6=-0.63583

Claim 28

The section of claim 1, wherein it is used for Mach numbers of adaptation Mad which, as a function of the maximum relative thickness e/1 of said section, vary according to formula (34) Mad=φ0+φ1(e/1) with φ0=-0.88636.10 φ1=+0.15320.10.