Mva
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FIXED-PINNED BEAM QUE 1 Matlab Code I=bb*hh^3/12; mu=7500*bb*hh; E=210e9; c=sqrt(E*I/mu); x=0:0.1:1; for i=1:4 f(i)=b(i)^2*c/2/pi; maxx(i)=0; for j=1:1:length(x) y(i,j)=sin(b(i)*x(j))-sinh(b(i)*x(j))+ (sin(b(i)*1)-sinh(b(i)*1))/(cos(b(i)*1)- cosh(b(i)*1))*(cosh(b(i)*x(j))-cos(b(i)*x(j))); maxx(i)=max(maxx(i),abs(y(i,j))); end end for i=1:4 for j=1:1:length(x) y(i,j)=y(i,j)/maxx(i); end end fprintf('\nFirst four natural frequencies in Hz'); display(f); plot(x,y(1,:),x,y(2,:),x,y(3,:),x,y(4,:)); title('Mode shape of 1st four natural freq'); legend('1st','2nd','3rd','4th'); RESULT First four natural frequencies in Hz f =
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mva
Transcript of Mva
FIXED-PINNED BEAMQUE 1
Matlab CodeI=bb*hh^3/12; mu=7500*bb*hh; E=210e9; c=sqrt(E*I/mu);
x=0:0.1:1; for i=1:4 f(i)=b(i)^2*c/2/pi; maxx(i)=0; for j=1:1:length(x) y(i,j)=sin(b(i)*x(j))-sinh(b(i)*x(j))+(sin(b(i)*1)-sinh(b(i)*1))/(cos(b(i)*1)-cosh(b(i)*1))*(cosh(b(i)*x(j))-cos(b(i)*x(j))); maxx(i)=max(maxx(i),abs(y(i,j))); end end for i=1:4 for j=1:1:length(x) y(i,j)=y(i,j)/maxx(i); end end fprintf('\nFirst four natural frequencies in Hz'); display(f); plot(x,y(1,:),x,y(2,:),x,y(3,:),x,y(4,:)); title('Mode shape of 1st four natural freq'); legend('1st','2nd','3rd','4th');
RESULT
First four natural frequencies in Hzf =
37.4837 , 121.4712 , 253.4399 , 433.3972
QUE 2Ansys APDL : Modal Analysis
MODE FREQ (Matlab) Hz
FREQ(Ansys)Hz
%Error
1 37.4837 37.471 0.03382 121.4712 121.40 0.05863 253.4399 253.45 0.003984 433.3972 434.55 0.2659
QUE 3Modal analysis is done in Ansys Workbench also and the following mode shapes were obtained for modes 1-4.On comparison, Striking similarity was observed to the mode shapes obtained using matlab
QUE 4Harmonic Analysis Using Ansys APDLFrequency Response when excited at x=0.5. Plotted for x at 0.25(uy_6) 0.5 (uy_3) and 0.75
Frequency Response when excited at x=0.25. Plotted for x at 0.25 (UY_5), 0.5(UY_3) and 0.75(UY_4)
