Ep 12 - About Elliptical wing & Solidworks
Ғылым және технология
The Matlab script
clc
clear
N = 9; % (number of segments - 1)
S = 25; % m^2
AR = 8; % Aspect ratio
lambda = 0.6; % Taper ratio
alpha_twist = -1; % Twist angle (deg)
i_w = 2; % wing setting angle (deg)
a_2d = 6.3; % lift curve slope (1/rad)
alpha_0 = -1.5; % zero-lift angle of attack (deg)
b = sqrt(AR*S); % wing span (m)
MAC = S/b; % Mean Aerodynamic Chord (m)
Croot = (1.5*(1+lambda)*MAC)/(1+lambda+lambda^2); % root chord (m)
theta = pi/(2*N):pi/(2*N):pi/2;
alpha = i_w+alpha_twist:-alpha_twist/(N-1):i_w;
% segment’s angle of attack
z = (b/2)*cos(theta);
c = Croot * (1 - (1-lambda)*cos(theta)); % Mean Aerodynamics
Chord at each segment (m)
mu = c * a_2d / (4 * b);
LHS = mu .* (alpha-alpha_0)/57.3; % Left Hand Side
% Solving N equations to find coefficients A(i):
for i=1:N
for j=1:N
B(i,j) = sin((2*j-1) * theta(i)) * (1 + (mu(i) * (2*j-1)) /
sin(theta(i)));
end
end
A=B\transpose(LHS);
for i = 1:N
sum1(i) = 0;
sum2(i) = 0;
for j = 1 : N
sum1(i) = sum1(i) + (2*j-1) * A(j)*sin((2*j-1)*theta(i));
sum2(i) = sum2(i) + A(j)*sin((2*j-1)*theta(i));
end
end
CL = 4*b*sum2 ./ c;
CL1=[0 CL(1) CL(2) CL(3) CL(4) CL(5) CL(6) CL(7) CL(8) CL(9)];
y_s=[b/2 z(1) z(2) z(3) z(4) z(5) z(6) z(7) z(8) z(9)];
plot(y_s,CL1,’-o’)
grid
title(‘Lift distribution’)
xlabel(‘Semi-span location (m)’)
ylabel (‘Lift coefficient’)
CL_wing = pi * AR * A(1)
Пікірлер: 13
Hi there, very interesting. I am making a 12" span catapult glider and was interested in using an elliptical wing from sheet balsa. Thanks for sharing this video.
How would you do the same wing to have it use a CNC to make a top and bottom mold? So I would cut the wing from foam then use carbon/kevlar and epoxy resign on top of the foam core and use the molds to mold everything together.
how do you make a dome tip Which must follow the plan view's shape? its the most difficult question about it...
Sir, what about the wing tip? how to draw it? I tried Extrude then a custom cut.. but that didn't work out as i thought it would, any help? Thanks!
@MightyWings
7 жыл бұрын
+Abd-ullah El-Sayed i will prepare a video for that. Thank you for your suggestion!
Hai how to insert new plane on chord line and how to insert Airfoil in that new plane?????? Please elaborate
thanks, sir.. this was really great.. :)
hey mighty wing can you do a structural (static non linear ) analysis on a real wing including the wing skin?
@MightyWings
7 жыл бұрын
+alexander yayne hi, i've tried but for rc modellism, was too much and very complex task. In any case, the assembly should be almost perfect, without overlapping, all the boundaries should be well defined. The other important part is for material properties, e.g. mechanical properties of the wood are anisotropic (depends on the direction of the fibers), or what about the skin? You have to consider the type of analysis since during fly, there is some frequency oscillation of the wing... A big big mess, but is possiblle
Hello Sir, I am trying to design a flying wing using the same theories given in chapter 5. The code given is for tapered wings, and I want to find the lift distribution for the swept wings... So can you write a new MatLab code for calculating lift distribution for swept wings? This could help me a lot, and can save my time too.
@MightyWings
7 жыл бұрын
+Siddhesh Kabure i can try, but not guarantee
@siddheshkabure8019
7 жыл бұрын
Thank you for accepting my request... At the end of the 5th chapter, there are numbers of unsolved problems. Can you please make a video for solving any one from it(Swept-wing design problem).
Elliptical lift distribution (washout or twist) works well at low air speeds near stall but can generate issues related to extra drag and poor trim at higher air speeds. An elliptical plan form wing may be better in some applications.