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tallakt/foilsjekte.jl

Last active July 14, 2019 21:42
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Foil sjekte
Raw
foilsjekte.jl
using Plots
using Optim
MS_KNOTS = 1.943844
KG_LBS = 2.204623
KW_HP = 1.341022
M_FEET = 3.28084
# Dimensjoner på båten (i meter, kg etc)
# https://marex.no/wp-content/uploads/2016/12/Duckie-Catalog.pdf
l = 6.5
b = 2.46
m = 1400
m_pass = 6 * 80
m_tot = m + m_pass
g = 9.81
# hastigheter
vv = 0.5:0.5:10.0 # ca 20 knop
# foil parametre
# http://airfoiltools.com/airfoil/details?airfoil=clarky-il
rho = 1000
wingspan = b
n_wings = 3.0
aspect = 15
area = wingspan ^2 / aspect * n_wings
c_l = 1.2 # Reynolds number approx 200.000 .. 2.000.000
g_e = 60 # at reynolds 200.000
c_d = c_l / 60.0 # skin friction?
POLAR_FILE = [
-3.500 0.0091 0.01659 0.00877 -0.0916 0.9112 0.0772
-3.250 0.0342 0.01609 0.00829 -0.0910 0.9027 0.0811
-3.000 0.0668 0.01553 0.00768 -0.0915 0.8975 0.0871
-2.750 0.0940 0.01485 0.00710 -0.0912 0.8900 0.0985
-2.500 0.1221 0.01403 0.00642 -0.0910 0.8825 0.1304
-2.250 0.1479 0.01328 0.00605 -0.0905 0.8741 0.2081
-2.000 0.1751 0.01271 0.00578 -0.0901 0.8662 0.2941
-1.750 0.1998 0.01226 0.00560 -0.0894 0.8568 0.3729
-1.500 0.2249 0.01156 0.00536 -0.0885 0.8491 0.4994
-1.250 0.2429 0.01087 0.00534 -0.0860 0.8383 0.6774
-1.000 0.2709 0.01036 0.00534 -0.0841 0.8309 0.8768
-0.750 0.3315 0.01030 0.00523 -0.0899 0.8231 0.9730
-0.500 0.3953 0.01014 0.00489 -0.0970 0.8170 1.0000
-0.250 0.4182 0.01015 0.00480 -0.0960 0.8055 1.0000
0.000 0.4424 0.01016 0.00470 -0.0952 0.7954 1.0000
0.250 0.4680 0.01015 0.00455 -0.0945 0.7864 1.0000
0.500 0.4915 0.01020 0.00453 -0.0935 0.7750 1.0000
0.750 0.5161 0.01024 0.00447 -0.0927 0.7644 1.0000
1.000 0.5419 0.01026 0.00437 -0.0920 0.7544 1.0000
1.250 0.5656 0.01032 0.00437 -0.0911 0.7423 1.0000
1.500 0.5899 0.01039 0.00437 -0.0902 0.7308 1.0000
1.750 0.6149 0.01046 0.00436 -0.0895 0.7196 1.0000
2.000 0.6402 0.01053 0.00433 -0.0887 0.7080 1.0000
2.250 0.6641 0.01061 0.00436 -0.0877 0.6945 1.0000
2.500 0.6883 0.01071 0.00440 -0.0868 0.6807 1.0000
2.750 0.7126 0.01081 0.00444 -0.0859 0.6666 1.0000
3.000 0.7370 0.01092 0.00449 -0.0851 0.6519 1.0000
3.250 0.7612 0.01104 0.00456 -0.0842 0.6360 1.0000
3.500 0.7852 0.01117 0.00462 -0.0832 0.6187 1.0000
3.750 0.8091 0.01133 0.00468 -0.0823 0.6003 1.0000
4.000 0.8324 0.01152 0.00480 -0.0812 0.5801 1.0000
4.250 0.8553 0.01174 0.00494 -0.0801 0.5580 1.0000
4.500 0.8781 0.01201 0.00508 -0.0790 0.5358 1.0000
4.750 0.9005 0.01231 0.00530 -0.0779 0.5124 1.0000
5.000 0.9227 0.01266 0.00551 -0.0768 0.4911 1.0000
5.250 0.9450 0.01300 0.00576 -0.0758 0.4700 1.0000
5.500 0.9671 0.01335 0.00602 -0.0747 0.4502 1.0000
5.750 0.9892 0.01371 0.00630 -0.0737 0.4321 1.0000
6.000 1.0116 0.01408 0.00660 -0.0727 0.4164 1.0000
6.250 1.0345 0.01444 0.00693 -0.0719 0.4033 1.0000
6.500 1.0576 0.01483 0.00730 -0.0711 0.3917 1.0000
6.750 1.0804 0.01525 0.00766 -0.0703 0.3808 1.0000
7.000 1.1032 0.01563 0.00805 -0.0695 0.3699 1.0000
7.250 1.1262 0.01602 0.00848 -0.0687 0.3598 1.0000
7.500 1.1486 0.01648 0.00890 -0.0679 0.3499 1.0000
7.750 1.1705 0.01686 0.00933 -0.0669 0.3391 1.0000
8.000 1.1918 0.01726 0.00978 -0.0659 0.3278 1.0000
8.250 1.2120 0.01769 0.01023 -0.0647 0.3155 1.0000
8.500 1.2310 0.01811 0.01066 -0.0634 0.3022 1.0000
8.750 1.2490 0.01852 0.01110 -0.0618 0.2876 1.0000
9.000 1.2663 0.01891 0.01155 -0.0602 0.2720 1.0000
9.250 1.2826 0.01932 0.01203 -0.0584 0.2533 1.0000
9.500 1.2960 0.01984 0.01253 -0.0563 0.2317 1.0000
9.750 1.3072 0.02048 0.01314 -0.0538 0.2074 1.0000
10.000 1.3158 0.02138 0.01392 -0.0512 0.1848 1.0000
10.250 1.3246 0.02239 0.01486 -0.0487 0.1663 1.0000
10.500 1.3333 0.02347 0.01590 -0.0464 0.1524 1.0000
10.750 1.3420 0.02458 0.01699 -0.0442 0.1408 1.0000
11.000 1.3494 0.02581 0.01818 -0.0421 0.1314 1.0000
11.250 1.3609 0.02682 0.01927 -0.0404 0.1222 1.0000
11.500 1.3704 0.02799 0.02047 -0.0387 0.1126 1.0000
11.750 1.3775 0.02935 0.02184 -0.0370 0.1040 1.0000
12.000 1.3859 0.03069 0.02323 -0.0355 0.0937 1.0000
12.250 1.3920 0.03227 0.02483 -0.0339 0.0811 1.0000
]
clark_cls = POLAR_FILE[:,2]
clark_cds = POLAR_FILE[:,3]
function calc_c_d(c_l, coeff)
coeff[1] + coeff[2] * c_l + coeff[3] * c_l^2 + coeff[4] * c_l ^3
end
function cost_fun(coeffs)
sum((clark_cds .- map(c_l -> calc_c_d(c_l, coeffs), clark_cls)).^2)
end
opt = optimize(cost_fun, [0.0, 0.0, 0.0, 0.0])
minimizer = Optim.minimizer(opt)
function clark_c_d(c_l)
calc_c_d(c_l, minimizer)
end
function adjust_cl_for_aspect_ratio(aspect, c_l, c_d)
c_d + c_l^2 / pi / aspect
end
c_l_max = maximum(clark_cls)
lift_max_foil = 1 ./ 2 .* rho .* vv.^2 .* c_l_max .* area
actual_c_l = c_l_max .* (min.(g * m_tot, lift_max_foil) ./ lift_max_foil)
actual_c_d = adjust_cl_for_aspect_ratio.(aspect, actual_c_l, clark_c_d.(actual_c_l))
actual_lift = 1 ./ 2 .* rho .* vv.^2 .* actual_c_l .* area
actual_foil_drag = 1 ./ 2 .* rho .* vv.^2 .* actual_c_d .* area
power_foil = actual_foil_drag .* vv / 1000.0
# displacement hull
# bruker regnearket på https://www.boatdesign.net/threads/calculating-power-for-displacement-boats.38487/
slr = vv ./ MS_KNOTS ./ sqrt(l / M_FEET)
# Gerr Method A
shp = max.(0.0, (m_tot .- actual_lift ./ 9.81)) ./ KG_LBS ./ (10.665 ./ slr).^3
power_displacement = shp .* KW_HP
# https://en.wikipedia.org/wiki/Hull_speed
v_hull = 1.34 * sqrt(l / M_FEET) * MS_KNOTS
p0 = plot([v_hull, v_hull], [0.0, 30.0], labels = "")
p0 = plot!(p0, vv, [power_foil, power_displacement, power_foil + power_displacement], labels=["P Foil" "P Displacement" "Sum P"], lw = 2.0, ylims = (0, 30), xlims = (0,maximum(vv)), ylabel = "kW", xlabel = "m/s")
p1 = plot([v_hull, v_hull], [0.0, m_tot * g / 10], labels = "")
p1 = plot!(p1, vv, actual_lift / 10, lw = 2.0, labels = "Lift of foil [daN]")
p2 = plot(vv, [actual_c_d actual_c_l], labels = ["C_L" "C_D"], lw = 2.0)
p3 = plot(vv, (power_foil + power_displacement) * 100 ./ vv, lw = 2.0, labels = "daN propulsion")
plot(p0, p1, p2, p3, layout = (2,2), size = (1200, 1000))
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