1 files changed, 47 insertions, 0 deletions
diff --git a/wing_scripts/stringersBeamExample.m b/wing_scripts/stringersBeamExample.m
new file mode 100644
index 0000000..cd3bcb6
--- /dev/null
+++ b/wing_scripts/stringersBeamExample.m
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+close all; 
+force = 8000; % lbs
+stringer_A = 0.5; % in^2
+thickness = 0.04; % in
+
+top_stringers_y = 6; % in
+middle_stringers_y = 2; % in
+
+I = 2*stringer_A*top_stringers_y^2 + 2*stringer_A*middle_stringers_y^2;
+
+% solve for shear stress distribution.  this calc ignores the thickness of
+% the web between teh stringers (assumes bending taken by stringers)
+% V / (I * t) * int(y*da)
+
+shear_top_web = force / (I*thickness) * top_stringers_y * stringer_A;
+shear_middle_web = shear_top_web + (force / (I*thickness) * middle_stringers_y * stringer_A);
+
+figure; grid on; hold on;set(gcf,'color',[1 1 1]);
+
+
+plot([shear_top_web shear_top_web],[middle_stringers_y top_stringers_y],'linewidth',2);
+plot([shear_middle_web shear_middle_web],[-middle_stringers_y middle_stringers_y],'linewidth',2);
+plot([shear_top_web shear_top_web],[-middle_stringers_y -top_stringers_y],'linewidth',2);
+
+plot([0 shear_top_web],[top_stringers_y top_stringers_y],'linewidth',2);
+plot([0 shear_top_web],[-top_stringers_y -top_stringers_y],'linewidth',2);
+plot([shear_middle_web shear_top_web],[middle_stringers_y middle_stringers_y],'linewidth',2);
+plot([shear_middle_web shear_top_web],[-middle_stringers_y -middle_stringers_y],'linewidth',2);
+xlabel('shear stress (lb/in^2)','fontsize',16,'fontweight','bold');ylabel('Distance from Center (in)','fontsize',16,'fontweight','bold')
+set(gca,'FontSize',16,'fontweight','bold');
+
+%Alternate approach.. compute change in bending stress at each stringer to
+%find the change in shear load
+
+%at top stringer
+d_sigma = force * top_stringers_y / I;  %(lbs/in^2)
+d_force_top = d_sigma * stringer_A;
+
+%at middle stringer..
+d_sigma = force * middle_stringers_y / I;  %(lbs/in^2)
+d_force_middle = d_force_top + d_sigma*stringer_A;
+
+%check if load balances
+check_load = 2*d_force_top*4 + d_force_middle*4;
+
+
+